open-vaf 0.4.2

A compiler frontend for VerilogA aimed predominently at compact modelling
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/* ******************************************************************************
   **************** COPYRIGHT NOTICE(Originator: Michael Schroter)***************
   ******************************************************************************

The terms under which the HICUM/L2 software is provided are as follows:

Software is distributed as is, completely without warranty or service
support. Michael Schroter and his team members are not liable for the
condition or performance of the software.

Michael Schroter owns the copyright and grants users a perpetual,
irrevocable, worldwide, non-exclusive, royalty-free license with respect
to the software as set forth below.

Michael Schroter hereby disclaims all implied warranties.

Michael Schroter grants the users the right to modify, copy, and
redistribute the software and documentation, both within the user's
organization and externally, subject to the following restrictions.

1. The users agree not to charge for the model owner's code itself but may
   charge for additions, extensions, or support.

2. In any product based on the software, the users agree to acknowledge
   Michael Schroter who developed the model and software. This
   acknowledgment shall appear in the product documentation.

3. Redistributions to others of source code and documentation must retain
   the copyright notice, disclaimer, and list of conditions.

4. Redistributions to others in binary form must reproduce the copyright
   notice, disclaimer, and list of conditions in the documentation
   and/or other materials provided with the distribution
*/

//******************************************************************************
//******************************************************************************

//HICUM Level/2 Version 2.4.0: A Verilog-A Description

/* ****** 28-03-2017, update to HICUM/L2 v2.4.0 *******************************

01/17 (AP): Increased the maximum values of ibets and ahc.
            Replaced calculation of Vciei by Vbiei and Vbici to avoid the
            dependence on the ci-ei branch.
03/17 (AP): Increased ranges for the parameters ahc and ibets.
            Added Gmin to all operating point conductances. Futher added a
            conditional statement for BETAAC to prevent division by zero
            Added new model for avalanche breakdown for high-voltages
            Changed conditional statement for avalanche breakdown calculation
            Changed versioning scheme

*/

/* ****** 31-08-2015, update to HICUM/L2 v2.34 ********************************

03/15 (AP): Added Qbf=0 to transit time calculation for low currents.
            Changed parameter range for grading factors of capacitances
            (excluding 1).
            Added parameter aick for smoothing the ICK(VCEi) curve.
08/15 (AP): Fixed wrong calculation of go when including avalanche breakdown
            Changed conditional statement for NQS effects (is now enabled only
            if both alit AND alqf are greater than zero).
            Implementation of the peripheral substrate capacitance.
            Added a term to avoid numerical issues in the QJCMOD macro.

*/

/* ****** 11-06-2013, update to HICUM/L2 v2.33 ********************************

05/13 (AP): Moved OP-value calculation out of noise block.
            Added TK and DTSH to the operating point values.
            Avoided division by zero for BETADC and BETAAC.
            Added an additional compiler flag for enabling operating point
            values also during transient simulations.

08/13 (AP): Simplified betadc section for noise calculations.

09/13 (AP): Changed ranges of alit and alqf back to including 0. Altered the
            conditional statements for correlated noise and NQS accordingly.
			Also, added correct backward compatibility for NQS effects in 2.1.
            Moved assignment of voltage variables after the Model_Initialization
            block.
            Added check for ibets > 0 to all blocks using tunneling current.
            Added more descriptive names for noise sources.
            Added abs() to all white-noise sources.

*/

/* ****** 27-03-2013, update to HICUM/L2 v2.32 ********************************

11/12 (AP): Calculation of operating point values inside the VA-code.
            Calculation can be removed completely from the code by removing the
            compiler flag CALC_OP.
03/13 (AP): Change of the conditional statement for turning barrier effects on
            and off.
04/13 (AP): Corrected the bug for the flicker noise calculation.

*/

//******** 11-05-2012, update to HICUM/L2 v2.31 ********************************

//03/12: Introduction of "type" model parameter to switch between "NPN" & "PNP"
//       type of devices
//03/12: Correlated Noise: Conditional loop for preventing negative values under
//       square root
//02/12: Correlated Noise implementation but without Filter approach (small code)
// Changed to temperature dependence of Rth now using alrth
// Simplification of the lateral NQS modeling in order to reduce the number of
// calculated derivatives.
// Changed to default values of the vertical NQS effect parameters.

//********** Update to HICUM/L2 v2.30 ******************************************
// The code contains the following new implementation compared to v2.24:

// Accurate modeling of transfer current and gm in medium current range with.
// Bias dependent weight factor hjEi.
// Weight factor hf0 for low current minority charge.
// Explicit physics-based formulation for BC barrier effect on minority charge.
// Improved formulation for the critical current.
// Added flicker noise across emitter resistance.
// Added temperature dependence of RTH.
// Use of mrei and mrep for temperature dependence of IREIs and IREPs.
// Added Gmin also between internal collector and emitter node.
// Usage of "ddx" operator only for determination of capacitances from the
// corresponding diffusion charges (Qdei, Qdci).
// The following effects are turned on by setting flcomp = 2.3 (as larger)
// * Temperature dependence of tef0 has been turned off.
// * Temperature dependence of hfe and hfc is turned on.
// * Modified formulation of temperature dependent internal BE recombination current &
//   peripheral current

//*********End Update Hicum/L2 v2.30********************************************

//******************************************************************************
//This code contains a Verilog-A implementation of Vertical Non-Quasi-Static(NQS)
//Effects using adjunct gyrator networks. To turn on this effect please set FLNQS=1.
//Although Vertical NQS effects have been taken into account in HICUM from the very
//beginning (see original FTN code and built-in v2.1 HICUM model inside most of the
//existing circuit simulators) their implementation has been based on Weil's approach.
//However, using Verilog, it is presently not possible to implement Weil's approach,
//since there does not exist access to previous time-steps of the simulator.
//The nearly available Verilog-A solution reproduces the results of previous
//HICUM versions (cf. documentation).
//******************************************************************************

// ***************Bug fix and optimization*************
// 04/08: New range has been defined for FDQR0.
// 11/07: Bugs have been fixed in macro HICFCI and HICQFC
// 10/06: in @(initial_model), external if-block for HICTUN_T removed
// 11/06: within HICQFC, minor changes made for LATB<=0.01;
// also HICFCI and HICFCT are changed accordingly
// to ensure correct derivatives
// Upper limit of FGEO parameter was changed to infinity.
// 12/06: expressions for Cdei and Cdci are corrected not to include
// Ccdei and Cbdci respectively (used in Crbi expression).

// 01/06: FCdf1_dw assigned expression (missing in v2.21)
// FCa and FCa1 are found to have same expression: FCa is omitted in those cases
// FCa1 written instead of FCa in the expression for FCf_ci
// Thermal node "tnode" set as external
// zetasct = mg+1-2.5 changed to zetasct = mg-1.5;
// Code optimization: Temperature dependent parts are modeled in two separate blocks:
// within @(initial_model) when self-heating is OFF
// outside @(initial_model) when self-heating is ON
// 03/06 : Further fix
// vlim_t,ibcis_t,ibcxs_t,itss_t,iscs_t considered in compatibility block
// ddt() operators are separated in contribution expressions.
// FLCOMP parameter is given different values
// 05/06:
// all if-else blocks marked with begin-end
// unused variables deleted
// all series resistors and RTH are allowed to have a minimum value MIN_R
// only tunneling current source contribution within if-then-else
// 06/06: HICRBI deleted and instead the code changed (hyperbolic smoothing in
// conductivity modulation part) and put in relevant portion of the code.
// 07/06: ddx() operator used to find out capacitances from charges:
// QJMODF,QJMOD,HICJQ changed accordingly
// Lateral NQS effect modified with ddx() operator.
// HICFCT included for downward compatibility reason.
// Few macros are taken inside the code: HICICK, HICAVL, HICTUN (more optimized),
// internal base resistance (Qjci included under conductivity modulation, hyperbolic smoothing used)
// Gmin added at (bi,ei) and (bi,ci) branches.
// 08/06: Units added in the parameter descriptions.

// *********************************************************************************
// 06/06: Comment on NODE COLLAPSING:
// Presently this verilog code permits a minimum of 1 milli-Ohm resistance for any
// series resistance as well as for thermal resistance RTH. If any of the resistance
// values drops below this minimum value, the corresponding nodes are shorted with
// zero voltage contribution. We want the model compilers/simulators deal this
// situation in such a manner that the corresponding node is COLLAPSED.
// We expect that the simulators should permit current contribution statement
// for any branch with resistance value more than (or equal to) 1 milli-Ohm without
// any Convergence problem. In fact, we wish NOT to have to use a voltage contribution
// statement in our Verilog code, except as an indication for the model compiler/simulator
// to interpret a zero branch voltage as NODE-COLLAPSING action.
// **********************************************************************************

`ifdef insideADMS
 `define MODEL @(initial_model)
 `define NOISE @(noise)
 `define ATTR(txt) (*txt*)
`else
 `define MODEL
 `define NOISE
 `define ATTR(txt)
`endif

// Comment this line, if calculation of operating point values should be omitted
`define CALC_OP
// Uncomment this line to reduce calculation of OP values only for DC simulations
//`define OP_STATIC

`define VPT_thresh      1.0e2
`define Dexp_lim        80.0
`define Cexp_lim        80.0
`define DFa_fj          1.921812
`define RTOLC           1.0e-5
`define l_itmax         100
`define TMAX            326.85
`define TMIN            -100.0
`define LN_EXP_LIMIT    11.0
`define MIN_R           0.001
//`define Gmin            1.0e-12
`define Gmin      $simparam("gmin",1e-12)  //suggested by L.L

//ADS
`include "constants.vams"
`include "disciplines.vams"
//`include "compact.vams"

//Spectre
//`include "constants.h"
//`include "discipline.h"

//////////////Explicit Capacitance and Charge Expression///////////////

// DEPLETION CHARGE CALCULATION
// Hyperbolic smoothing used; no punch-through
// INPUT:
//  c_0		: zero-bias capacitance
//  u_d		: built-in voltage
//  z		: exponent coefficient
//  a_j		: control parameter for C peak value at high forward bias
//  U_cap	: voltage across junction
// IMPLICIT INPUT:
//  VT		: thermal voltage
// OUTPUT:
//  Qz		: depletion Charge
//  C		: depletion capacitance
`define QJMODF(c_0,u_d,z,a_j,U_cap,C,Qz)\
    if(c_0 > 0.0) begin\
        DFV_f	 = u_d*(1.0-exp(-ln(a_j)/z));\
        DFv_e	 = (DFV_f-U_cap)/VT;\
        DFs_q	 = sqrt(DFv_e*DFv_e+`DFa_fj);\
        DFs_q2	 = (DFv_e+DFs_q)*0.5;\
        DFv_j	 = DFV_f-VT*DFs_q2;\
        DFdvj_dv = DFs_q2/DFs_q;\
        DFb	     = ln(1.0-DFv_j/u_d);\
        DFC_j1   = c_0*exp(-z*DFb)*DFdvj_dv;\
        C		 = DFC_j1+a_j*c_0*(1.0-DFdvj_dv);\
        DFQ_j	 = c_0*u_d*(1.0-exp(DFb*(1.0-z)))/(1.0-z);\
        Qz	     = DFQ_j+a_j*c_0*(U_cap-DFv_j);\
    end else begin\
        C        = 0.0;\
        Qz	     = 0.0;\
    end

////////////////////////////////////////////////////////////////


//////////////Explicit Capacitance and Charge Expression///////////////


// DEPLETION CHARGE CALCULATION CONSIDERING PUNCH THROUGH
// smoothing of reverse bias region (punch-through)
// and limiting to a_j=Cj,max/Cj0 for forward bias.
// Important for base-collector and collector-substrate junction
// INPUT:
//  c_0		: zero-bias capacitance
//  u_d		: built-in voltage
//  z 		: exponent coefficient
//  a_j		: control parameter for C peak value at high forward bias
//  v_pt	: punch-through voltage (defined as qNw^2/2e)
//  U_cap	: voltage across junction
// IMPLICIT INPUT:
//  VT		: thermal voltage
// OUTPUT:
//  Qz		: depletion charge
//  C		: depletion capacitance
`define QJMOD(c_0,u_d,z,a_j,v_pt,U_cap,C,Qz)\
    if(c_0 > 0.0) begin\
        Dz_r	= z/4.0;\
        Dv_p	= v_pt-u_d;\
        DV_f	= u_d*(1.0-exp(-ln(a_j)/z));\
        DC_max	= a_j*c_0;\
        DC_c	= c_0*exp((Dz_r-z)*ln(v_pt/u_d));\
        Dv_e	= (DV_f-U_cap)/VT;\
        if(Dv_e < `Cexp_lim) begin\
            De	    = exp(Dv_e);\
            De_1	= De/(1.0+De);\
            Dv_j1	= DV_f-VT*ln(1.0+De);\
        end else begin\
            De_1	= 1.0;\
            Dv_j1	= U_cap;\
        end\
        Da	    = 0.1*Dv_p+4.0*VT;\
        Dv_r	= (Dv_p+Dv_j1)/Da;\
        if(Dv_r < `Cexp_lim) begin\
            De	    = exp(Dv_r);\
            De_2	= De/(1.0+De);\
            Dv_j2	= -Dv_p+Da*(ln(1.0+De)-exp(-(Dv_p+DV_f)/Da));\
        end else begin\
            De_2	= 1.0;\
            Dv_j2	= Dv_j1;\
        end\
        Dv_j4	= U_cap-Dv_j1;\
        DCln1	= ln(1.0-Dv_j1/u_d);\
        DCln2	= ln(1.0-Dv_j2/u_d);\
        Dz1	    = 1.0-z;\
        Dzr1	= 1.0-Dz_r;\
        DC_j1	= c_0*exp(DCln2*(-z))*De_1*De_2;\
        DC_j2	= DC_c*exp(DCln1*(-Dz_r))*(1.0-De_2);\
        DC_j3	= DC_max*(1.0-De_1);\
        C		= DC_j1+DC_j2+DC_j3;\
        DQ_j1	= c_0*(1.0-exp(DCln2*Dz1))/Dz1;\
        DQ_j2	= DC_c*(1.0-exp(DCln1*Dzr1))/Dzr1;\
        DQ_j3	= DC_c*(1.0-exp(DCln2*Dzr1))/Dzr1;\
        Qz	    = (DQ_j1+DQ_j2-DQ_j3)*u_d+DC_max*Dv_j4;\
    end else begin\
        C	    = 0.0;\
        Qz	    = 0.0;\
    end


// DEPLETION CHARGE & CAPACITANCE CALCULATION SELECTOR
// Dependent on junction punch-through voltage
// Important for collector related junctions
`define HICJQ(c_0,u_d,z,v_pt,U_cap,C,Qz)\
    if(v_pt < `VPT_thresh) begin\
        `QJMOD(c_0,u_d,z,2.4,v_pt,U_cap,C,Qz)\
    end else begin\
        `QJMODF(c_0,u_d,z,2.4,U_cap,C,Qz)\
    end


// A CALCULATION NEEDED FOR COLLECTOR MINORITY CHARGE FORMULATION
// INPUT:
//  zb,zl       : zeta_b and zeta_l (model parameters, TED 10/96)
//  w           : normalized injection width
// OUTPUT:
// hicfcio      : function of equation (2.1.17-10)
`define HICFCI(zb,zl,w,hicfcio,dhicfcio_dw)\
    z       = zb*w;\
    lnzb    = ln(1+zb*w);\
    if(z > 1.0e-6) begin\
        x               = 1.0+z;\
        a               = x*x;\
        a2              = 0.250*(a*(2.0*lnzb-1.0)+1.0);\
        a3              = (a*x*(3.0*lnzb-1.0)+1.0)/9.0;\
        r               = zl/zb;\
        hicfcio         = ((1.0-r)*a2+r*a3)/zb;\
        dhicfcio_dw     = ((1.0-r)*x+r*a)*lnzb;\
    end else begin\
        a               = z*z;\
        a2              = 3.0+z-0.25*a+0.10*z*a;\
        a3              = 2.0*z+0.75*a-0.20*a*z;\
        hicfcio         = (zb*a2+zl*a3)*w*w/6.0;\
        dhicfcio_dw     = (1+zl*w)*(1+z)*lnzb;\
    end


// NEEDED TO CALCULATE WEIGHTED ICCR COLLECTOR MINORITY CHARGE
// INPUT:
//  z : zeta_b or zeta_l
//  w : normalized injection width
// OUTPUT:
//  hicfcto     : output
//  dhicfcto_dw : derivative of output wrt w
`define HICFCT(z,w,hicfcto,dhicfcto_dw)\
    a = z*w;\
    lnz = ln(1+z*w);\
    if (a > 1.0e-6) begin\
        hicfcto     = (a - lnz)/z;\
        dhicfcto_dw = a / (1.0 + a);\
    end else begin\
        hicfcto     = 0.5 * a * w;\
        dhicfcto_dw = a;\
    end


// COLLECTOR CURRENT SPREADING CALCULATION
// collector minority charge incl. 2D/3D current spreading (TED 10/96)
// INPUT:
//  Ix                          : forward transport current component (itf)
//  I_CK                        : critical current
//  FFT_pcS                     : dependent on fthc and thcs (parameters)
// IMPLICIT INPUT:
//  ahc, latl, latb             : model parameters
//  VT                          : thermal voltage
// OUTPUT:
//  Q_fC, Q_CT: actual and ICCR (weighted) hole charge
//  T_fC, T_cT: actual and ICCR (weighted) transit time
//  Derivative dfCT_ditf not properly implemented yet
`define HICQFC(Ix,I_CK,FFT_pcS,Q_fC,Q_CT,T_fC,T_cT)\
    Q_fC            = FFT_pcS*Ix;\
    FCa             = 1.0-I_CK/Ix;\
    FCrt            = sqrt(FCa*FCa+ahc);\
    FCa_ck          = 1.0-(FCa+FCrt)/(1.0+sqrt(1.0+ahc));\
    FCdaick_ditf    = (FCa_ck-1.0)*(1-FCa)/(FCrt*Ix);\
    if(latb > latl) begin\
        FCz             = latb-latl;\
        FCxl            = 1.0+latl;\
        FCxb            = 1.0+latb;\
        if(latb > 0.01) begin\
            FCln            = ln(FCxb/FCxl);\
            FCa1            = exp((FCa_ck-1.0)*FCln);\
            FCd_a           = 1.0/(latl-FCa1*latb);\
            FCw             = (FCa1-1.0)*FCd_a;\
            FCdw_daick      = -FCz*FCa1*FCln*FCd_a*FCd_a;\
            FCa1            = ln((1.0+latb*FCw)/(1.0+latl*FCw));\
            FCda1_dw        = latb/(1.0+latb*FCw) - latl/(1.0+latl*FCw);\
        end else begin\
            FCf1            = 1.0-FCa_ck;\
            FCd_a           = 1.0/(1.0+FCa_ck*latb);\
            FCw             = FCf1*FCd_a;\
            FCdw_daick      = -1.0*FCd_a*FCd_a*FCxb*FCd_a;\
            FCa1            = FCz*FCw;\
            FCda1_dw        = FCz;\
        end\
        FCf_CT          = 2.0/FCz;\
        FCw2            = FCw*FCw;\
        FCf1            = latb*latl*FCw*FCw2/3.0+(latb+latl)*FCw2/2.0+FCw;\
        FCdf1_dw        = latb*latl*FCw2 + (latb+latl)*FCw + 1.0;\
        `HICFCI(latb,latl,FCw,FCf2,FCdf2_dw)\
        `HICFCI(latl,latb,FCw,FCf3,FCdf3_dw)\
        FCf_ci          = FCf_CT*(FCa1*FCf1-FCf2+FCf3);\
        FCdfc_dw        = FCf_CT*(FCa1*FCdf1_dw+FCda1_dw*FCf1-FCdf2_dw+FCdf3_dw);\
        FCdw_ditf       = FCdw_daick*FCdaick_ditf;\
        FCdfc_ditf      = FCdfc_dw*FCdw_ditf;\
        if(flcomp == 0.0 || flcomp == 2.1) begin\
            `HICFCT(latb,FCw,FCf2,FCdf2_dw)\
            `HICFCT(latl,FCw,FCf3,FCdf3_dw)\
            FCf_CT          = FCf_CT*(FCf2-FCf3);\
            FCdfCT_dw       = FCf_CT*(FCdf2_dw-FCdf3_dw);\
            FCdfCT_ditf     = FCdfCT_dw*FCdw_ditf;\
        end else begin\
            FCf_CT          = FCf_ci;\
            FCdfCT_ditf     = FCdfc_ditf;\
        end\
    end else begin\
        if(latb > 0.01) begin\
            FCd_a           = 1.0/(1.0+FCa_ck*latb);\
            FCw             = (1.0-FCa_ck)*FCd_a;\
            FCdw_daick      = -(1.0+latb)*FCd_a*FCd_a;\
        end else begin\
            FCw             = 1.0-FCa_ck-FCa_ck*latb;\
            FCdw_daick      = -(1.0+latb);\
        end\
        FCw2            = FCw*FCw;\
        FCz             = latb*FCw;\
        FCz_1           = 1.0+FCz;\
        FCd_f           = 1.0/(FCz_1);\
        FCf_ci          = FCw2*(1.0+FCz/3.0)*FCd_f;\
        FCdfc_dw        = 2.0*FCw*(FCz_1+FCz*FCz/3.0)*FCd_f*FCd_f;\
        FCdw_ditf       = FCdw_daick*FCdaick_ditf;\
        FCdfc_ditf      = FCdfc_dw*FCdw_ditf;\
        if(flcomp == 0.0 || flcomp == 2.1) begin\
            if (FCz > 0.001) begin\
                FCf_CT          = 2.0*(FCz_1*ln(FCz_1)-FCz)/(latb*latb*FCz_1);\
                FCdfCT_dw       = 2.0*FCw*FCd_f*FCd_f;\
            end else begin\
                FCf_CT          = FCw2*(1.0-FCz/3.0)*FCd_f;\
                FCdfCT_dw       = 2.0*FCw*(1.0-FCz*FCz/3.0)*FCd_f*FCd_f;\
            end\
            FCdfCT_ditf     = FCdfCT_dw*FCdw_ditf;\
        end else begin\
            FCf_CT          = FCf_ci;\
            FCdfCT_ditf     = FCdfc_ditf;\
        end\
    end\
    Q_CT    = Q_fC*FCf_CT*exp((FFdVc-vcbar)/VT);\
    Q_fC    = Q_fC*FCf_ci*exp((FFdVc-vcbar)/VT);\
    T_fC    = FFT_pcS*exp((FFdVc-vcbar)/VT)*(FCf_ci+Ix*FCdfc_ditf)+Q_fC/VT*FFdVc_ditf;\
    T_cT    = FFT_pcS*exp((FFdVc-vcbar)/VT)*(FCf_CT+Ix*FCdfCT_ditf)+Q_CT/VT*FFdVc_ditf;

// TRANSIT-TIME AND STORED MINORITY CHARGE
// INPUT:
//  itf         : forward transport current
//  I_CK        : critical current
//  T_f         : transit time    \
//  Q_f         : minority charge / for low current
// IMPLICIT INPUT:
//  tef0, gtfe, fthc, thcs, ahc, latl, latb     : model parameters
// OUTPUT:
//  T_f         : transit time    \
//  Q_f         : minority charge / transient analysis
//  T_fT        : transit time    \
//  Q_fT        : minority charge / ICCR (transfer current)
//  Q_bf        : excess base charge
`define HICQFF(itf,I_CK,T_f,Q_f,T_fT,Q_fT,Q_bf)\
    if(itf < 1.0e-6*I_CK) begin\
        Q_fT            = Q_f;\
        T_fT            = T_f;\
        Q_bf            = 0;\
    end else begin\
        FFitf_ick = itf/I_CK;\
        FFdTef  = tef0_t*exp(gtfe*ln(FFitf_ick));\
        FFdQef  = FFdTef*itf/(1+gtfe);\
        if (icbar<0.05*(vlim/rci0)) begin\
            FFdVc = 0;\
            FFdVc_ditf = 0;\
        end else begin\
            FFib    = (itf-I_CK)/icbar;\
            if (FFib < -1.0e10) begin\
                FFib = -1.0e10;\
            end\
            FFfcbar = (FFib+sqrt(FFib*FFib+acbar))/2.0;\
            FFdib_ditf = FFfcbar/sqrt(FFib*FFib+acbar)/icbar;\
            FFdVc = vcbar*exp(-1.0/FFfcbar);\
            FFdVc_ditf = FFdVc/(FFfcbar*FFfcbar)*FFdib_ditf;\
        end\
        FFdQbfb = (1-fthc)*thcs_t*itf*(exp(FFdVc/VT)-1);\
        FFdTbfb = FFdQbfb/itf+(1-fthc)*thcs_t*itf*exp(FFdVc/VT)/VT*FFdVc_ditf;\
        FFic    = 1-1.0/FFitf_ick;\
        FFw     = (FFic+sqrt(FFic*FFic+ahc))/(1+sqrt(1+ahc));\
        FFdQfhc = thcs_t*itf*FFw*FFw*exp((FFdVc-vcbar)/VT);\
        FFdTfhc = FFdQfhc*(1.0/itf*(1.0+2.0/(FFitf_ick*sqrt(FFic*FFic+ahc)))+1.0/VT*FFdVc_ditf);\
        if(latb <= 0.0 && latl <= 0.0) begin\
             FFdQcfc = fthc*FFdQfhc;\
             FFdTcfc = fthc*FFdTfhc;\
             FFdQcfcT = FFdQcfc;\
             FFdTcfcT = FFdTcfc;\
        end else begin\
             `HICQFC(itf,I_CK,fthc*thcs_t,FFdQcfc,FFdQcfcT,FFdTcfc,FFdTcfcT)\
        end\
        FFdQbfc = (1-fthc)*FFdQfhc;\
        FFdTbfc = (1-fthc)*FFdTfhc;\
        Q_fT	= hf0_t*Q_f+FFdQbfb+FFdQbfc+hfe_t*FFdQef+hfc_t*FFdQcfcT;\
        T_fT	= hf0_t*T_f+FFdTbfb+FFdTbfc+hfe_t*FFdTef+hfc_t*FFdTcfcT;\
        Q_f	    = Q_f+(FFdQbfb+FFdQbfc)+FFdQef+FFdQcfc;\
        T_f 	= T_f+(FFdTbfb+FFdTbfc)+FFdTef+FFdTcfc;\
        Q_bf    = FFdQbfb+FFdQbfc;\
      end




// IDEAL DIODE (WITHOUT CAPACITANCE):
// conductance calculation not required
// INPUT:
//  IS, IST     : saturation currents (model parameter related)
//  UM1         : ideality factor
//  U           : branch voltage
// IMPLICIT INPUT:
//  VT          : thermal voltage
// OUTPUT:
//  Iz          : diode current
`define HICDIO(IS,IST,UM1,U,Iz)\
    DIOY    = U/(UM1*VT);\
    if (IS > 0.0) begin\
        if (DIOY > `Dexp_lim) begin\
            le      = (1 + (DIOY - `Dexp_lim));\
            DIOY    = `Dexp_lim;\
        end else begin\
            le      = 1;\
        end\
        le      = le*limexp(DIOY);\
        Iz      = IST*(le-1.0);\
        if(DIOY <= -14.0) begin\
            Iz      = -IST;\
        end\
    end else begin\
        Iz      = 0.0;\
    end



// TEMPERATURE UPDATE OF JUNCTION CAPACITANCE RELATED PARAMETERS
// INPUT:
//  mostly model parameters
//  x           : zero bias junction capacitance
//  y           : junction built-in potential
//  z           : grading co-efficient
//  w           : ratio of maximum to zero-bias value of capacitance or punch-through voltage
//  is_al       : condition factor to check what "w" stands for
//  vgeff       : band-gap voltage
// IMPLICIT INPUT:
//  VT          : thermal voltage
//  vt0,qtt0,ln_qtt0,mg : other model variables
// OUTPUT:
//  c_j_t               : temperature update of "c_j"
//  vd_t                : temperature update of "vd0"
//  w_t                 : temperature update of "w"
`define TMPHICJ(c_j,vd0,z,w,is_al,vgeff,c_j_t,vd_t,w_t)\
    if (c_j > 0.0) begin\
        vdj0    = 2*vt0*ln(exp(vd0*0.5/vt0)-exp(-0.5*vd0/vt0));\
        vdjt    = vdj0*qtt0+vgeff*(1-qtt0)-mg*VT*ln_qtt0;\
        vdt     = vdjt+2*VT*ln(0.5*(1+sqrt(1+4*exp(-vdjt/VT))));\
        vd_t    = vdt;\
        c_j_t   = c_j*exp(z*ln(vd0/vd_t));\
        if (is_al == 1) begin\
            w_t = w*vd_t/vd0;\
        end else begin\
            w_t = w;\
        end\
    end else begin\
        c_j_t   = c_j;\
        vd_t    = vd0;\
        w_t     = w;\
    end



module hicumL2va (c,b,e,s,tnode);

//Node definitions

inout           c,b,e,s,tnode;
electrical      c,b,e,s,ci,ei,bp,bi,si;
electrical	    xf1,xf2;
electrical      xf;  //RC nw

electrical      tnode;

electrical 	    n1,n2;


//Branch definitions
branch          (b,bp)          br_bbp_i;
branch          (b,bp)          br_bbp_v;
branch          (ci,c)          br_cic_i;
branch          (ci,c)          br_cic_v;
branch          (ei,e)          br_eie_i;
branch          (ei,e)          br_eie_v;
branch          (bp,bi)         br_bpbi_i;
branch          (bp,bi)         br_bpbi_v;
branch          (si,s)          br_sis_i;
branch          (si,s)          br_sis_v;
branch          (bi,ei)         br_biei;
branch          (bi,ci)         br_bici;
branch          (ci,bi)         br_cibi;
branch          (ci,ei)         br_ciei;
branch          (ei,ci)         br_eici;
branch          (bp,e)          br_bpe;
branch          (b,e)           br_be;
branch          (bp,ei)         br_bpei;
branch          (bp,ci)         br_bpci;
branch          (b,ci)          br_bci;
branch          (si,ci)         br_sici;
branch          (s,c)           br_sc;   // External SC branch required for CSCp
branch          (bp,si)         br_bpsi;
branch          (tnode )        br_sht;

//Excess phase network for ITF
branch		(xf1 )		br_bxf1;
branch		(xf1 )		br_cxf1;
branch		(xf2 )		br_bxf2;
branch		(xf2 )		br_cxf2;

//Excess phase network for QF

branch    (xf )     br_bxf;  //for RC nw
branch    (xf )     br_cxf;  //for RC nw
branch	(n1 )	b_n1;
branch	(n2 )	b_n2;

// -- ###########################################################
// -- ###########     Parameters initialization  ################
// -- ###########################################################


//Transfer current
parameter real c10      = 2.0E-30       from [0:1]      `ATTR(info="GICCR constant" unit="A^2s");
parameter real qp0      = 2.0E-14       from (0:1]      `ATTR(info="Zero-bias hole charge" unit="Coul");
parameter real ich      = 0.0           from [0:inf)    `ATTR(info="High-current correction for 2D and 3D effects" unit="A"); //`0' signifies infinity
parameter real hf0      = 1.0           from [0:inf)    `ATTR(info="Weight factor for the low current minority charge");
parameter real hfe      = 1.0           from [0:inf]    `ATTR(info="Emitter minority charge weighting factor in HBTs");
parameter real hfc      = 1.0           from [0:inf]    `ATTR(info="Collector minority charge weighting factor in HBTs");
parameter real hjei     = 1.0           from [0:100]    `ATTR(info="B-E depletion charge weighting factor in HBTs");
parameter real ahjei    = 0.0           from [0:100]    `ATTR(info="Parameter describing the slope of hjEi(VBE)");
parameter real rhjei    = 1.0           from (0:10]     `ATTR(info="Smoothing parameter for hjEi(VBE) at high voltage");
parameter real hjci     = 1.0           from [0:100]    `ATTR(info="B-C depletion charge weighting factor in HBTs");

//Base-Emitter diode currents
parameter real ibeis    = 1.0E-18       from [0:1]      `ATTR(info="Internal B-E saturation current" unit="A");
parameter real mbei     = 1.0           from (0:10]     `ATTR(info="Internal B-E current ideality factor");
parameter real ireis    = 0.0           from [0:1]      `ATTR(info="Internal B-E recombination saturation current" unit="A");
parameter real mrei     = 2.0           from (0:10]     `ATTR(info="Internal B-E recombination current ideality factor");
parameter real ibeps    = 0.0           from [0:1]      `ATTR(info="Peripheral B-E saturation current" unit="A");
parameter real mbep     = 1.0           from (0:10]     `ATTR(info="Peripheral B-E current ideality factor");
parameter real ireps    = 0.0           from [0:1]      `ATTR(info="Peripheral B-E recombination saturation current" unit="A");
parameter real mrep     = 2.0           from (0:10]     `ATTR(info="Peripheral B-E recombination current ideality factor");
parameter real mcf      = 1.0           from (0:10]     `ATTR(info="Non-ideality factor for III-V HBTs");

//Transit time for excess recombination current at b-c barrier
parameter real tbhrec   = 0.0           from [0:inf)    `ATTR(info="Base current recombination time constant at B-C barrier for high forward injection" unit="s");

//Base-Collector diode currents
parameter real ibcis    = 1.0E-16       from [0:1.0]    `ATTR(info="Internal B-C saturation current" unit="A");
parameter real mbci     = 1.0           from (0:10]     `ATTR(info="Internal B-C current ideality factor");
parameter real ibcxs    = 0.0           from [0:1.0]    `ATTR(info="External B-C saturation current" unit="A");
parameter real mbcx     = 1.0           from (0:10]     `ATTR(info="External B-C current ideality factor");

//Base-Emitter tunneling current
parameter real ibets    = 0.0           from [0:50]     `ATTR(info="B-E tunneling saturation current" unit="A");
parameter real abet     = 40            from [0:inf)    `ATTR(info="Exponent factor for tunneling current");
parameter integer tunode= 1             from [0:1]      `ATTR(info="Specifies the base node connection for the tunneling current"); // =1 signifies perimeter node

//Base-Collector avalanche current
parameter real favl     = 0.0           from [0:inf)    `ATTR(info="Avalanche current factor" unit="1/V");
parameter real qavl     = 0.0           from [0:inf)    `ATTR(info="Exponent factor for avalanche current" unit="Coul");
parameter real kavl     = 0.0           from [0:3]      `ATTR(info="Flag/factor for turning strong avalanche on");
parameter real alfav    = 0.0                           `ATTR(info="Relative TC for FAVL" unit="1/K");
parameter real alqav    = 0.0                           `ATTR(info="Relative TC for QAVL" unit="1/K");
parameter real alkav    = 0.0                           `ATTR(info="Relative TC for KAVL" unit="1/K");

//Series resistances
parameter real rbi0     = 0.0           from [0:inf)    `ATTR(info="Zero bias internal base resistance" unit="Ohm");
parameter real rbx      = 0.0           from [0:inf)    `ATTR(info="External base series resistance" unit="Ohm");
parameter real fgeo     = 0.6557        from [0:inf]    `ATTR(info="Factor for geometry dependence of emitter current crowding");
parameter real fdqr0    = 0.0           from [-0.5:100] `ATTR(info="Correction factor for modulation by B-E and B-C space charge layer");
parameter real fcrbi    = 0.0           from [0:1]      `ATTR(info="Ratio of HF shunt to total internal capacitance (lateral NQS effect)");
parameter real fqi      = 1.0           from [0:1]      `ATTR(info="Ration of internal to total minority charge");
parameter real re       = 0.0           from [0:inf)    `ATTR(info="Emitter series resistance" unit="Ohm");
parameter real rcx      = 0.0           from [0:inf)    `ATTR(info="External collector series resistance" unit="Ohm");

//Substrate transistor
parameter real itss     = 0.0           from [0:1.0]    `ATTR(info="Substrate transistor transfer saturation current" unit="A");
parameter real msf      = 1.0           from (0:10]     `ATTR(info="Forward ideality factor of substrate transfer current");
parameter real iscs     = 0.0           from [0:1.0]    `ATTR(info="C-S diode saturation current" unit="A");
parameter real msc      = 1.0           from (0:10]     `ATTR(info="Ideality factor of C-S diode current");
parameter real tsf      = 0.0           from [0:inf)    `ATTR(info="Transit time for forward operation of substrate transistor" unit="s");

//Intra-device substrate coupling
parameter real rsu      = 0.0           from [0:inf)    `ATTR(info="Substrate series resistance" unit="Ohm");
parameter real csu      = 0.0           from [0:inf)    `ATTR(info="Substrate shunt capacitance" unit="F");

//Depletion Capacitances
parameter real cjei0    = 1.0E-20       from [0:inf)    `ATTR(info="Internal B-E zero-bias depletion capacitance" unit="F");
parameter real vdei     = 0.9           from (0:10]     `ATTR(info="Internal B-E built-in potential" unit="V");
parameter real zei      = 0.5	        from (0:1)      `ATTR(info="Internal B-E grading coefficient");
parameter real ajei     = 2.5           from [1:inf)    `ATTR(info="Ratio of maximum to zero-bias value of internal B-E capacitance");
parameter real cjep0    = 1.0E-20       from [0:inf)    `ATTR(info="Peripheral B-E zero-bias depletion capacitance" unit="F");
parameter real vdep     = 0.9           from (0:10]     `ATTR(info="Peripheral B-E built-in potential" unit="V");
parameter real zep      = 0.5           from (0:1)      `ATTR(info="Peripheral B-E grading coefficient");
parameter real ajep     = 2.5           from [1:inf)    `ATTR(info="Ratio of maximum to zero-bias value of peripheral B-E capacitance");
parameter real cjci0    = 1.0E-20       from [0:inf)    `ATTR(info="Internal B-C zero-bias depletion capacitance" unit="F");
parameter real vdci     = 0.7           from (0:10]     `ATTR(info="Internal B-C built-in potential" unit="V");
parameter real zci      = 0.4           from (0:1)      `ATTR(info="Internal B-C grading coefficient");
parameter real vptci    = 100           from (0:100]    `ATTR(info="Internal B-C punch-through voltage" unit="V");
parameter real cjcx0    = 1.0E-20       from [0:inf)    `ATTR(info="External B-C zero-bias depletion capacitance" unit="F");
parameter real vdcx     = 0.7           from (0:10]     `ATTR(info="External B-C built-in potential" unit="V");
parameter real zcx      = 0.4           from (0:1)      `ATTR(info="External B-C grading coefficient");
parameter real vptcx    = 100           from (0:100]    `ATTR(info="External B-C punch-through voltage" unit="V");
parameter real fbcpar   = 0.0           from [0:1]      `ATTR(info="Partitioning factor of parasitic B-C cap");
parameter real fbepar   = 1.0           from [0:1]      `ATTR(info="Partitioning factor of parasitic B-E cap");
parameter real cjs0     = 0.0           from [0:inf)    `ATTR(info="C-S zero-bias depletion capacitance" unit="F");
parameter real vds      = 0.6           from (0:10]     `ATTR(info="C-S built-in potential" unit="V");
parameter real zs       = 0.5           from (0:1)      `ATTR(info="C-S grading coefficient");
parameter real vpts     = 100           from (0:100]    `ATTR(info="C-S punch-through voltage" unit="V");
parameter real cscp0    = 0.0           from [0:inf)    `ATTR(info="Perimeter S-C zero-bias depletion capacitance" unit="F");
parameter real vdsp     = 0.6           from [0:10]     `ATTR(info="Perimeter S-C built-in potential" unit="V");
parameter real zsp      = 0.5           from (0:1)      `ATTR(info="Perimeter S-C grading coefficient");
parameter real vptsp    = 100           from (0:100]    `ATTR(info="Perimeter S-C punch-through voltage" unit="V");

//Diffusion Capacitances
parameter real t0       = 0.0           from [0:inf)    `ATTR(info="Low current forward transit time at VBC=0V" unit="s");
parameter real dt0h     = 0.0           from (-inf:inf) `ATTR(info="Time constant for base and B-C space charge layer width modulation" unit="s");
parameter real tbvl     = 0.0           from (-inf:inf) `ATTR(info="Time constant for modeling carrier jam at low VCE" unit="s");
parameter real tef0     = 0.0           from [0:inf)    `ATTR(info="Neutral emitter storage time" unit="s");
parameter real gtfe     = 1.0           from (0:10]     `ATTR(info="Exponent factor for current dependence of neutral emitter storage time");
parameter real thcs     = 0.0           from [0:inf)    `ATTR(info="Saturation time constant at high current densities" unit="s");
parameter real ahc      = 0.1           from (0:50]     `ATTR(info="Smoothing factor for current dependence of base and collector transit time");
parameter real fthc     = 0.0           from [0:1]      `ATTR(info="Partitioning factor for base and collector portion");
parameter real rci0     = 150           from (0:inf)    `ATTR(info="Internal collector resistance at low electric field" unit="Ohm");
parameter real vlim     = 0.5           from (0:10]     `ATTR(info="Voltage separating ohmic and saturation velocity regime" unit="V");
parameter real vces     = 0.1           from [0:1]      `ATTR(info="Internal C-E saturation voltage" unit="V");
parameter real vpt      = 100.0         from (0:inf]    `ATTR(info="Collector punch-through voltage" unit="V"); // `0' signifies infinity
parameter real aick     = 1e-3          from (0:10]     `ATTR(info="Smoothing term for ICK");
parameter real delck    = 2.0           from (0:10]     `ATTR(info="Fitting factor for critical current");
parameter real tr       = 0.0           from [0:inf)    `ATTR(info="Storage time for inverse operation" unit="s");
parameter real vcbar    = 0.0           from [0:1]      `ATTR(info="Barrier voltage" unit="V");
parameter real icbar    = 0.0           from [0:1]      `ATTR(info="Normalization parameter" unit="A");
parameter real acbar    = 0.01          from (0:10]     `ATTR(info="Smoothing parameter for barrier voltage");

//Isolation Capacitances
parameter real cbepar   = 0.0           from [0:inf)    `ATTR(info="Total parasitic B-E capacitance" unit="F");
parameter real cbcpar   = 0.0           from [0:inf)    `ATTR(info="Total parasitic B-C capacitance" unit="F");

//Non-quasi-static Effect
parameter real alqf     = 0.167         from [0:1]      `ATTR(info="Factor for additional delay time of minority charge");
parameter real alit     = 0.333         from [0:1]      `ATTR(info="Factor for additional delay time of transfer current");
parameter integer flnqs = 0             from [0:1]      `ATTR(info="Flag for turning on and off of vertical NQS effect");

//Noise
parameter real kf       = 0.0           from [0:inf)    `ATTR(info="Flicker noise coefficient");
parameter real af       = 2.0           from (0:10]     `ATTR(info="Flicker noise exponent factor");
parameter integer cfbe  = -1            from [-2:-1]    `ATTR(info="Flag for determining where to tag the flicker noise source");
parameter integer flcono = 0             from [0:1]     `ATTR(info="Flag for turning on and off of correlated noise implementation");


parameter real kfre     = 0.0           from [0:inf)    `ATTR(info="Emitter resistance flicker noise coefficient");
parameter real afre     = 2.0           from (0:10]     `ATTR(info="Emitter resistance flicker noise exponent factor");


//Lateral Geometry Scaling (at high current densities)
parameter real latb     = 0.0           from [0:inf)    `ATTR(info="Scaling factor for collector minority charge in direction of emitter width");
parameter real latl     = 0.0           from [0:inf)    `ATTR(info="Scaling factor for collector minority charge in direction of emitter length");

//Temperature dependence
parameter real vgb      = 1.17          from (0:10]     `ATTR(info="Bandgap voltage extrapolated to 0 K" unit="V");
parameter real alt0     = 0.0                           `ATTR(info="First order relative TC of parameter T0" unit="1/K");
parameter real kt0      = 0.0                           `ATTR(info="Second order relative TC of parameter T0");
parameter real zetaci   = 0.0           from [-10:10]   `ATTR(info="Temperature exponent for RCI0");
parameter real alvs     = 0.0                           `ATTR(info="Relative TC of saturation drift velocity" unit="1/K");
parameter real alces    = 0.0                           `ATTR(info="Relative TC of VCES" unit="1/K");
parameter real zetarbi  = 0.0           from [-10:10]   `ATTR(info="Temperature exponent of internal base resistance");
parameter real zetarbx  = 0.0           from [-10:10]   `ATTR(info="Temperature exponent of external base resistance");
parameter real zetarcx  = 0.0           from [-10:10]   `ATTR(info="Temperature exponent of external collector resistance");
parameter real zetare   = 0.0           from [-10:10]   `ATTR(info="Temperature exponent of emitter resistance");
parameter real zetacx   = 1.0           from [-10:10]   `ATTR(info="Temperature exponent of mobility in substrate transistor transit time");
parameter real vge      = 1.17          from (0:10]     `ATTR(info="Effective emitter bandgap voltage" unit="V");
parameter real vgc      = 1.17          from (0:10]     `ATTR(info="Effective collector bandgap voltage" unit="V");
parameter real vgs      = 1.17          from (0:10]     `ATTR(info="Effective substrate bandgap voltage" unit="V");
parameter real f1vg     =-1.02377e-4                    `ATTR(info="Coefficient K1 in T-dependent band-gap equation");
parameter real f2vg     = 4.3215e-4                     `ATTR(info="Coefficient K2 in T-dependent band-gap equation");
parameter real zetact   = 3.0           from [-10:10]   `ATTR(info="Exponent coefficient in transfer current temperature dependence");
parameter real zetabet  = 3.5           from [-10:10]   `ATTR(info="Exponent coefficient in B-E junction current temperature dependence");
parameter real alb      = 0.0                           `ATTR(info="Relative TC of forward current gain for V2.1 model" unit="1/K");
parameter real dvgbe    = 0             from [-10:10]   `ATTR(info="Bandgap difference between B and B-E junction used for hjEi0 and hf0" unit="V");
parameter real zetahjei = 1             from [-10:10]   `ATTR(info="Temperature coefficient for ahjEi");
parameter real zetavgbe = 1             from [-10:10]   `ATTR(info="Temperature coefficient for hjEi0");

//Self-Heating
parameter integer flsh  = 0             from [0:2]      `ATTR(info="Flag for turning on and off self-heating effect");
parameter real rth      = 0.0           from [0:inf)    `ATTR(info="Thermal resistance" unit="K/W");
parameter real zetarth  = 0.0           from [-10:10]   `ATTR(info="Temperature coefficient for Rth");
parameter real alrth    = 0.0           from [-10:10]   `ATTR(info="First order relative TC of parameter Rth" unit="1/K");
parameter real cth      = 0.0           from [0:inf)    `ATTR(info="Thermal capacitance" unit="J/W");

//Compatibility with V2.1
parameter real flcomp = 0.0             from [0:inf)    `ATTR(info="Flag for compatibility with v2.1 model (0=v2.1)");

//Circuit simulator specific parameters
parameter real tnom     = 27.0                          `ATTR(info="Temperature at which parameters are specified" unit="C");
parameter real dt       = 0.0                           `ATTR(info="Temperature change w.r.t. chip temperature for particular transistor" unit="K");
parameter integer  type = 1		 from [-1:1] exclude 0  `ATTR(info="For transistor type NPN(+1) or PNP (-1)");

//
//======================== Transistor model formulation ===================
//

    //Declaration of variables

    //Temperature and drift
    real VT,Tdev,qtt0,ln_qtt0,r_VgVT,V_gT,dT,k;
    real ireis_t,ibeis_t,ibcxs_t,ibcis_t,iscs_t,cjci0_t;
    real cjs0_t,cscp0_t,rci0_t,vlim_t,vces_t,thcs_t,tef0_t,rbi0_t;
    real t0_t,vdei_t,vdci_t,vpts_t,vptsp_t,itss_t,tsf_t;
    real c10_t,cjei0_t,qp0_t,vdcx_t,vptcx_t,cjcx01_t,cjcx02_t;
    real qjcx0_t_i,qjcx0_t_ii,cratio_t;
    real ibeps_t,ireps_t,cjep0_t;
    real ajei_t,qavl_t,favl_t,kavl_t,ibets_t,abet_t,vptci_t,vdep_t,ajep_t,zetatef;
    real k1,k2,dvg0,vge_t,vgb_t,vgbe_t,vds_t,vdsp_t,vt0,Tnom,Tamb,a,avs;
    real zetabci,zetabcxt,zetasct,vgbe0,mg,vgb_t0,vge_t0,vgbe_t0,vgbc0,vgsc0;

    real cbcpar1,cbcpar2,cbepar2,cbepar1,Oich,Ovpt,Otbhrec;

    //Charges, capacitances and currents
    real Qjci,Qjei,Qjep;
    real it,ibei,irei,ibci,ibep,irep,ibh_rec;
    real Qdei,Qdci,qrbi;
    real ibet,iavl;
    real ijbcx,ijsc,Qjs,Qscp,HSUM,HSI_Tsu,Qdsu;

    //Base resistance and self-heating power
    real pterm,rth_t;

    //Variables for macro TMPHICJ
    real  vdj0,vdjt,vdt;

    //Model initialization
    real k10,k20,C_1;

    //Model evaluation
    real Cjci,Cjcit,cc,Cjei,Cjep,CjCx_i,CjCx_ii,Cjs,Cscp;
    real itf,itr,Tf,Tr,VT_f,i_0f,i_0r,a_bpt,Q_0,Q_p,Q_bpt;
    real Orci0_t,b_q,I_Tf1,T_f0,Q_fT,T_fT,Q_bf;
    real ICKa,d1,a1,a11,Odelck,ick1,ick2;
    real A,a_h,Q_pT,d_Q,d_Q0;
    real Qf,Cdei,Qr,Cdci,Crbi;
    real ick,vc,vceff,cjcx01,cjcx02,HSa,HSb;
    integer l_it;

    //Variables for macros
    real  DIOY,le;//HICDIO
    real  FFfcbar,FFitf_ick,FFdQef,FFdTef,FFdQbfb,FFdTbfb,FFdQfhc,FFdTfhc,FFdQbfc,FFdTbfc,FFdQcfc,FFdTcfc,FFdQcfcT,FFdTcfcT,FFib,FFic,FFw,FFdVc,FFdVc_ditf,FFdib_ditf;//HICQFF
    real  FCz,FCw2,FCf1,FCf2,FCf3,FCf_ci,FCz_1,FCa1,FCa_ck,FCxl,FCxb;//HICQFC
    real  FCd_a,FCdaick_ditf,FCa,FCw,FCdw_daick,FCdfc_dw,FCdw_ditf,FCdfc_ditf,FCf_CT,FCdfCT_ditf,FCrt,FCln,lnz,FCda1_dw,FCdf1_dw,FCdf2_dw,FCdf3_dw,FCd_f,FCdfCT_dw;//HICQFC
    real  Dz_r,Dv_p,DV_f,DC_max,DC_c,Da,Dv_e,De,De_1,Dv_j1,Dv_r,De_2,Dv_j2,Dv_j4,DQ_j1,DQ_j2,DQ_j3,DCln1,DCln2,Dz1,Dzr1,DC_j1,DC_j2,DC_j3;//QJMOD
    real  DFV_f,DFv_e,DFv_j,DFb,DFQ_j,DFs_q,DFs_q2,DFdvj_dv,DFC_j1;//QJMODF
    real  z,a2,a3,r,x;//HICFCI
    real  lnzb; //HICFCT

    //Noise
    real fourkt,twoq,flicker_Pwr;
    real betadc;
    real n_w,n_1,n_2,sqrt_n2;
    //NQS
    real Ixf1,Ixf2,Qxf1,Qxf2,Vxf1,Vxf2,Itxf,Qdeix;
    real Vxf, Ixf, Qxf,fact;

    real hjei_vbe,vj,vj_z;
    real hjei0_t, ahjei_t, hf0_t, hfe_t, hfc_t;

    real i_re;

    real Vbiei, Vbici, Vciei, Vbpei, Vbpci, Vbci, Vsici, Vsc;

    // Model flags
    integer use_aval;

    real rbx_t;

    `ifdef CALC_OP
        (* desc="External (saturated) collector series resistance",        units="Ohm" *) real rcx_t;
        (* desc="Emitter series resistance",                               units="Ohm" *) real re_t;
        (* desc="Internal base resistance as calculated in the model",     units="Ohm" *) real rbi;
        (* desc="Total base resistance as calculated in the model",        units="Ohm" *) real rb;
    `else
        real rcx_t, re_t, rbi;
    `endif

    `ifdef CALC_OP
        (* desc="Base terminal current",                                   units="A"   *) real IB;
        (* desc="Collector terminal current",                              units="A"   *) real IC;
        (* desc="Substrate terminal current",                              units="A"   *) real IS;
        (* desc="Avalanche current",                                       units="A"   *) real IAVL;

        (* desc="External BE voltage",                                     units="V"   *) real VBE;
        (* desc="External BC voltage",                                     units="V"   *) real VBC;
        (* desc="External CE voltage",                                     units="V"   *) real VCE;
        (* desc="External SC voltage",                                     units="V"   *) real VSC;

        (* desc="Common emitter forward current gain"                                  *) real BETADC;
        (* desc="Internal transconductance",                               units="A/V" *) real GMi;
        (* desc="Transconductance of the parasitic substrate PNP",         units="A/V" *) real GMS;
        (* desc="Internal base-emitter (input) resistance",                units="Ohm" *) real RPIi;
        (* desc="External base-emitter (input) resistance",                units="Ohm" *) real RPIx;
        (* desc="Internal feedback resistance",                            units="Ohm" *) real RMUi;
        (* desc="External feedback resistance",                            units="Ohm" *) real RMUx;
        (* desc="Output resistance",                                       units="Ohm" *) real ROi;
        (* desc="Total internal BE capacitance",                           units="F"   *) real CPIi;
        (* desc="Total external BE capacitance",                           units="F"   *) real CPIx;
        (* desc="Total internal BC capacitance",                           units="F"   *) real CMUi;
        (* desc="Total external BC capacitance",                           units="F"   *) real CMUx;
        (* desc="CS junction capacitance",                                 units="F"   *) real CCS;
        (* desc="Small signal current gain"                                            *) real BETAAC;
        (* desc="Shunt capacitance across RBI as calculated in the model", units="F"   *) real CRBI;
        (* desc="Forward transit time",                                    units="s"   *) real TF;
        (* desc="Transit frequency",                                       units="Hz"  *) real FT;

        (* desc="Actual device temperature",                               units="K"   *) real TK;
        (* desc="Temperature increase due to self-heating",                units="K"   *) real DTSH;
    `endif


    //end of variables
analog function real test;
    input x;
    input y;
    real x,y;
    test = x*y;
endfunction

analog begin

`MODEL begin : Model_initialization

    Tnom    = tnom+`P_CELSIUS0;
    Tamb    = $temperature;
    vt0     = `P_K*Tnom /`P_Q;
    k10     = f1vg*Tnom*ln(Tnom);
    k20     = f2vg*Tnom;
    avs     = alvs*Tnom;
    vgb_t0  = vgb+k10+k20;
    vge_t0  = vge+k10+k20;
    vgbe_t0 = (vgb_t0+vge_t0)/2;
    vgbe0   = (vgb+vge)/2;
    vgbc0   = (vgb+vgc)/2;
    vgsc0   = (vgs+vgc)/2;
    mg      = 3-`P_Q*f1vg/`P_K;
    zetabci = mg+1-zetaci;
    zetabcxt= mg+1-zetacx;
    zetasct = mg-1.5;

    //Depletion capacitance splitting at b-c junction
    //Capacitances at peripheral and external base node
    C_1    = (1.0-fbcpar)*(cjcx0+cbcpar);
    if (C_1 >= cbcpar) begin
        cbcpar1 = cbcpar;
        cbcpar2 = 0.0;
        cjcx01  = C_1-cbcpar;
        cjcx02  = cjcx0-cjcx01;
    end else begin
        cbcpar1 = C_1;
        cbcpar2 = cbcpar-cbcpar1;
        cjcx01  = 0.0;
        cjcx02  = cjcx0;
    end

    //Parasitic b-e capacitance partitioning: No temperature dependence
    cbepar2 = fbepar*cbepar;
    cbepar1 = cbepar-cbepar2;

    //Avoid divide-by-zero and define infinity other way
    //High current correction for 2D and 3D effects
    if (ich != 0.0) begin
        Oich    = 1.0/ich;
    end else begin
        Oich    = 0.0;
    end

    //Base current recombination time constant at b-c barrier
    if (tbhrec != 0.0) begin
        Otbhrec = 1.0/tbhrec;
    end else begin
        Otbhrec = 0.0;
    end

    // Turn avalanche calculation on depending of parameters
    if ((favl > 0.0) && (cjci0 > 0.0)) begin
        use_aval = 1;
    end else begin
        use_aval = 0;
        iavl = 0.0; // Set iavl to zero in this case here, this avoids the else block later
    end

    // Temperature and resulting parameter drift
    if (flsh==0 || rth < `MIN_R) begin : Thermal_updat_without_self_heating
        Tdev    = Tamb+dt;
        if(Tdev < `TMIN + 273.15) begin
            Tdev = `TMIN + 273.15;
        end else begin
            if (Tdev > `TMAX + 273.15) begin
                Tdev = `TMAX + 273.15;
            end
        end
        VT      = `P_K*Tdev /`P_Q;
        dT      = Tdev-Tnom;
        qtt0    = Tdev/Tnom;
        ln_qtt0 = ln(qtt0);
        k1      = f1vg*Tdev*ln(Tdev);
        k2      = f2vg*Tdev;
        vgb_t   = vgb+k1+k2;
        vge_t   = vge+k1+k2;
        vgbe_t  = (vgb_t+vge_t)/2;

        //Internal b-e junction capacitance
        `TMPHICJ(cjei0,vdei,zei,ajei,1,vgbe0,cjei0_t,vdei_t,ajei_t)

        if (flcomp == 0.0 || flcomp == 2.1) begin
            V_gT     = 3.0*VT*ln_qtt0 + vgb*(qtt0-1.0);
            r_VgVT   = V_gT/VT;
            //Internal b-e diode saturation currents
            a        = mcf*r_VgVT/mbei - alb*dT;
            ibeis_t  = ibeis*exp(a);
            a        = mcf*r_VgVT/mrei - alb*dT;
            ireis_t  = ireis*exp(a);
            a        = mcf*r_VgVT/mbep - alb*dT;
            //Peripheral b-e diode saturation currents
            ibeps_t  = ibeps*exp(a);
            a        = mcf*r_VgVT/mrep - alb*dT;
            ireps_t  = ireps*exp(a);
            //Internal b-c diode saturation current
            a       = r_VgVT/mbci;
            ibcis_t = ibcis*exp(a);
            //External b-c diode saturation currents
            a       = r_VgVT/mbcx;
            ibcxs_t = ibcxs*exp(a);
            //Saturation transfer current for substrate transistor
            a       = r_VgVT/msf;
            itss_t  = itss*exp(a);
            //Saturation current for c-s diode
            a       = r_VgVT/msc;
            iscs_t  = iscs*exp(a);
            //Zero bias hole charge
            a        = vdei_t/vdei;
            qp0_t    = qp0*(1.0+0.5*zei*(1.0-a));
            //Voltage separating ohmic and saturation velocity regime
            a = vlim*(1.0-alvs*dT)*exp(zetaci*ln_qtt0);
            k = (a-VT)/VT;
            if (k < `LN_EXP_LIMIT) begin
                vlim_t = VT + VT*ln(1.0+exp(k));
            end else begin
                vlim_t = a;
            end
            //Neutral emitter storage time
            a        = 1.0+alb*dT;
            k        = 0.5*(a+sqrt(a*a+0.01));
            tef0_t   = tef0*qtt0/k;
        end else begin
            //Internal b-e diode saturation currents
            ibeis_t  = ibeis*exp(zetabet*ln_qtt0+vge/VT*(qtt0-1));
            if (flcomp>=2.3) begin
                ireis_t  = ireis*exp(mg/mrei*ln_qtt0+vgbe0/(mrei*VT)*(qtt0-1));
            end else begin
                ireis_t  = ireis*exp(0.5*mg*ln_qtt0+0.5*vgbe0/VT*(qtt0-1));
            end
            //Peripheral b-e diode saturation currents
            ibeps_t  = ibeps*exp(zetabet*ln_qtt0+vge/VT*(qtt0-1));
            if (flcomp>=2.3) begin
                ireps_t  = ireps*exp(mg/mrep*ln_qtt0+vgbe0/(mrep*VT)*(qtt0-1));
            end else begin
                ireps_t  = ireps*exp(0.5*mg*ln_qtt0+0.5*vgbe0/VT*(qtt0-1));
            end
            //Internal b-c diode saturation currents
            ibcis_t = ibcis*exp(zetabci*ln_qtt0+vgc/VT*(qtt0-1));
            //External b-c diode saturation currents
            ibcxs_t = ibcxs*exp(zetabcxt*ln_qtt0+vgc/VT*(qtt0-1));
            //Saturation transfer current for substrate transistor
            itss_t  = itss*exp(zetasct*ln_qtt0+vgc/VT*(qtt0-1));
            //Saturation current for c-s diode
            iscs_t  = iscs*exp(zetasct*ln_qtt0+vgs/VT*(qtt0-1));
            //Zero bias hole charge
            a       = exp(zei*ln(vdei_t/vdei));
            qp0_t   = qp0*(2.0-a);
            //Voltage separating ohmic and saturation velocity regime
            vlim_t  = vlim*exp((zetaci-avs)*ln_qtt0);
            //Neutral emitter storage time
            if (flcomp >= 2.3) begin
                tef0_t  = tef0;
            end else begin
                zetatef = zetabet-zetact-0.5;
                dvg0    = vgb-vge;
                tef0_t  = tef0*exp(zetatef*ln_qtt0-dvg0/VT*(qtt0-1));
            end
        end

        //GICCR prefactor
        c10_t   = c10*exp(zetact*ln_qtt0+vgb/VT*(qtt0-1));

        // Low-field internal collector resistance
        rci0_t  = rci0*exp(zetaci*ln_qtt0);

        //Voltage separating ohmic and saturation velocity regime
        //vlim_t  = vlim*exp((zetaci-avs)*ln_qtt0);

        //Internal c-e saturation voltage
        vces_t  = vces*(1+alces*dT);

        //Internal b-c diode saturation current
        //ibcis_t = ibcis*exp(zetabci*ln_qtt0+vgc/VT*(qtt0-1));

        //Internal b-c junction capacitance
        `TMPHICJ(cjci0,vdci,zci,vptci,0,vgbc0,cjci0_t,vdci_t,vptci_t)

        //Low-current forward transit time
        t0_t    = t0*(1+alt0*dT+kt0*dT*dT);

        //Saturation time constant at high current densities
        thcs_t  = thcs*exp((zetaci-1)*ln_qtt0);


        //Avalanche current factors
        favl_t  = favl*exp(alfav*dT);
        qavl_t  = qavl*exp(alqav*dT);
        kavl_t  = kavl*exp(alkav*dT);

        //Zero bias internal base resistance
        rbi0_t  = rbi0*exp(zetarbi*ln_qtt0);


        //Peripheral b-e junction capacitance
        `TMPHICJ(cjep0,vdep,zep,ajep,1,vgbe0,cjep0_t,vdep_t,ajep_t)

        //Tunneling current factors
        if (ibets > 0) begin : HICTUN_T
            real a_eg,ab,aa;
            ab      = 1.0;
            aa      = 1.0;
            a_eg=vgbe_t0/vgbe_t;
            if(tunode==1 && cjep0 > 0.0 && vdep >0.0) begin
                ab      = (cjep0_t/cjep0)*sqrt(a_eg)*vdep_t*vdep_t/(vdep*vdep);
                aa      = (vdep/vdep_t)*(cjep0/cjep0_t)*pow(a_eg,-1.5);
            end else if (tunode==0 && cjei0 > 0.0 && vdei >0.0) begin
                ab      = (cjei0_t/cjei0)*sqrt(a_eg)*vdei_t*vdei_t/(vdei*vdei);
                aa      = (vdei/vdei_t)*(cjei0/cjei0_t)*pow(a_eg,-1.5);
            end
            ibets_t = ibets*ab;
            abet_t  = abet*aa;
        end else begin
            ibets_t = 0;
            abet_t = 1;
        end


        //Temperature mapping for tunneling current is done inside HICTUN

        `TMPHICJ(1.0,vdcx,zcx,vptcx,0,vgbc0,cratio_t,vdcx_t,vptcx_t)
        cjcx01_t=cratio_t*cjcx01;
        cjcx02_t=cratio_t*cjcx02;


        //External b-c diode saturation currents
        //ibcxs_t       = ibcxs*exp(zetabcxt*ln_qtt0+vgc/VT*(qtt0-1));


        //Constant external series resistances
        rcx_t   = rcx*exp(zetarcx*ln_qtt0);
        rbx_t   = rbx*exp(zetarbx*ln_qtt0);
        re_t    = re*exp(zetare*ln_qtt0);

        //Forward transit time in substrate transistor
        tsf_t   = tsf*exp((zetacx-1.0)*ln_qtt0);

        //Capacitance for c-s junction
        `TMPHICJ(cjs0,vds,zs,vpts,0,vgsc0,cjs0_t,vds_t,vpts_t)
        /*Peripheral s-c capacitance
         * Note, thermal update only required for vds > 0
         * Save computional effort otherwise
         */
        if (vdsp > 0) begin
            `TMPHICJ(cscp0,vdsp,zsp,vptsp,0,vgsc0,cscp0_t,vdsp_t,vptsp_t)
        end else begin
            // Avoid uninitialized variables
            cscp0_t = cscp0;
            vdsp_t = vdsp;
            vptsp_t = vptsp;
        end

        ahjei_t = ahjei*exp(zetahjei*ln_qtt0);
        hjei0_t = hjei*exp(dvgbe/VT*(exp(zetavgbe*ln(qtt0))-1));
        hf0_t   = hf0*exp(dvgbe/VT*(qtt0-1));
        if (flcomp >= 2.3) begin
            hfe_t   = hfe*exp((vgb-vge)/VT*(qtt0-1));
            hfc_t   = hfc*exp((vgb-vgc)/VT*(qtt0-1));
        end else begin
            hfe_t    = hfe;
            hfc_t    = hfc;
        end

        rth_t    = rth*exp(zetarth*ln_qtt0)*(1+alrth*dT);

    end // of Thermal_update_without_self_heating

end     //of Model_initialization

Vbiei = type*V(br_biei);
Vbici = type*V(br_bici);
Vciei = Vbiei-Vbici;
Vbpei = type*V(br_bpei);
Vbpci = type*V(br_bpci);
Vbci  = type*V(br_bci);
Vsici = type*V(br_sici);
Vsc   = type*V(br_sc);

if (flsh!=0 && rth >= `MIN_R) begin : Thermal_update_with_self_heating
    Tdev    = Tamb+dt+V(br_sht);
    // Limit temperature to avoid FPEs in equations
    if(Tdev < `TMIN + 273.15) begin
        Tdev = `TMIN + 273.15;
    end else begin
        if (Tdev > `TMAX + 273.15) begin
            Tdev = `TMAX + 273.15;
        end
    end
    VT      = `P_K*Tdev /`P_Q;
    dT      = Tdev-Tnom;
    qtt0    = Tdev/Tnom;
    ln_qtt0 = ln(qtt0);
    k1      = f1vg*Tdev*ln(Tdev);
    k2      = f2vg*Tdev;
    vgb_t   = vgb+k1+k2;
    vge_t   = vge+k1+k2;
    vgbe_t  = (vgb_t+vge_t)/2;

    //Internal b-e junction capacitance
    `TMPHICJ(cjei0,vdei,zei,ajei,1,vgbe0,cjei0_t,vdei_t,ajei_t)

    if (flcomp == 0.0 || flcomp == 2.1) begin
        V_gT     = 3.0*VT*ln_qtt0 + vgb*(qtt0-1.0);
        r_VgVT   = V_gT/VT;
        //Internal b-e diode saturation currents
        a        = mcf*r_VgVT/mbei - alb*dT;
        ibeis_t  = ibeis*exp(a);
        a        = mcf*r_VgVT/mrei - alb*dT;
        ireis_t  = ireis*exp(a);
        a        = mcf*r_VgVT/mbep - alb*dT;
        //Peripheral b-e diode saturation currents
        ibeps_t  = ibeps*exp(a);
        a        = mcf*r_VgVT/mrep - alb*dT;
        ireps_t  = ireps*exp(a);
        //Internal b-c diode saturation current
        a       = r_VgVT/mbci;
        ibcis_t = ibcis*exp(a);
        //External b-c diode saturation currents
        a       = r_VgVT/mbcx;
        ibcxs_t = ibcxs*exp(a);
        //Saturation transfer current for substrate transistor
        a       = r_VgVT/msf;
        itss_t  = itss*exp(a);
        //Saturation current for c-s diode
        a       = r_VgVT/msc;
        iscs_t  = iscs*exp(a);
        //Zero bias hole charge
        a        = vdei_t/vdei;
        qp0_t    = qp0*(1.0+0.5*zei*(1.0-a));
        //Voltage separating ohmic and saturation velocity regime
        a = vlim*(1.0-alvs*dT)*exp(zetaci*ln_qtt0);
        k = (a-VT)/VT;
        if (k < `LN_EXP_LIMIT) begin
            vlim_t = VT + VT*ln(1.0+exp(k));
        end else begin
            vlim_t = a;
        end
        //Neutral emitter storage time
        a        = 1.0+alb*dT;
        k        = 0.5*(a+sqrt(a*a+0.01));
        tef0_t   = tef0*qtt0/k;
    end else begin
        //Internal b-e diode saturation currents
        ibeis_t  = ibeis*exp(zetabet*ln_qtt0+vge/VT*(qtt0-1));
        if (flcomp>=2.3) begin
            ireis_t  = ireis*exp(mg/mrei*ln_qtt0+vgbe0/(mrei*VT)*(qtt0-1));
        end else begin
            ireis_t  = ireis*exp(0.5*mg*ln_qtt0+0.5*vgbe0/VT*(qtt0-1));
        end
        //Peripheral b-e diode saturation currents
        ibeps_t  = ibeps*exp(zetabet*ln_qtt0+vge/VT*(qtt0-1));
        if (flcomp>=2.3) begin
            ireps_t  = ireps*exp(mg/mrep*ln_qtt0+vgbe0/(mrep*VT)*(qtt0-1));
        end else begin
            ireps_t  = ireps*exp(0.5*mg*ln_qtt0+0.5*vgbe0/VT*(qtt0-1));
        end
        //Internal b-c diode saturation currents
        ibcis_t = ibcis*exp(zetabci*ln_qtt0+vgc/VT*(qtt0-1));
        //External b-c diode saturation currents
        ibcxs_t = ibcxs*exp(zetabcxt*ln_qtt0+vgc/VT*(qtt0-1));
        //Saturation transfer current for substrate transistor
        itss_t  = itss*exp(zetasct*ln_qtt0+vgc/VT*(qtt0-1));
        //Saturation current for c-s diode
        iscs_t  = iscs*exp(zetasct*ln_qtt0+vgs/VT*(qtt0-1));
        //Zero bias hole charge
        a       = exp(zei*ln(vdei_t/vdei));
        qp0_t   = qp0*(2.0-a);
        //Voltage separating ohmic and saturation velocity regime
        vlim_t  = vlim*exp((zetaci-avs)*ln_qtt0);
        //Neutral emitter storage time
        if (flcomp >= 2.3) begin
            tef0_t  = tef0;
        end else begin
            zetatef = zetabet-zetact-0.5;
            dvg0    = vgb-vge;
            tef0_t  = tef0*exp(zetatef*ln_qtt0-dvg0/VT*(qtt0-1));
        end
    end

    //GICCR prefactor
    c10_t   = c10*exp(zetact*ln_qtt0+vgb/VT*(qtt0-1));

    // Low-field internal collector resistance
    rci0_t  = rci0*exp(zetaci*ln_qtt0);

    //Voltage separating ohmic and saturation velocity regime
    //vlim_t  = vlim*exp((zetaci-avs)*ln_qtt0);

    //Internal c-e saturation voltage
    vces_t  = vces*(1+alces*dT);

    //Internal b-c diode saturation current
    //ibcis_t = ibcis*exp(zetabci*ln_qtt0+vgc/VT*(qtt0-1));

    //Internal b-c junction capacitance
    `TMPHICJ(cjci0,vdci,zci,vptci,0,vgbc0,cjci0_t,vdci_t,vptci_t)

    //Low-current forward transit time
    t0_t    = t0*(1+alt0*dT+kt0*dT*dT);

    //Saturation time constant at high current densities
    thcs_t  = thcs*exp((zetaci-1)*ln_qtt0);


    //Avalanche current factors
    favl_t  = favl*exp(alfav*dT);
    qavl_t  = qavl*exp(alqav*dT);
    kavl_t  = kavl*exp(alkav*dT);

    //Zero bias internal base resistance
    rbi0_t  = rbi0*exp(zetarbi*ln_qtt0);


    //Peripheral b-e junction capacitance
    `TMPHICJ(cjep0,vdep,zep,ajep,1,vgbe0,cjep0_t,vdep_t,ajep_t)

    //Tunneling current factors
    if (ibets > 0 && (Vbpei < 0.0 || Vbiei < 0.0)) begin : HICTUN_T
        real a_eg,ab,aa;
        ab      = 1.0;
        aa      = 1.0;
        a_eg=vgbe_t0/vgbe_t;
        if(tunode==1 && cjep0 > 0.0 && vdep >0.0) begin
            ab      = (cjep0_t/cjep0)*sqrt(a_eg)*vdep_t*vdep_t/(vdep*vdep);
            aa      = (vdep/vdep_t)*(cjep0/cjep0_t)*pow(a_eg,-1.5);
        end else if (tunode==0 && cjei0 > 0.0 && vdei >0.0) begin
            ab      = (cjei0_t/cjei0)*sqrt(a_eg)*vdei_t*vdei_t/(vdei*vdei);
            aa      = (vdei/vdei_t)*(cjei0/cjei0_t)*pow(a_eg,-1.5);
        end
        ibets_t = ibets*ab;
        abet_t  = abet*aa;
    end else begin
        ibets_t = 0;
        abet_t = 1;
    end


    //Temperature mapping for tunneling current is done inside HICTUN

    `TMPHICJ(1.0,vdcx,zcx,vptcx,0,vgbc0,cratio_t,vdcx_t,vptcx_t)
    cjcx01_t=cratio_t*cjcx01;
    cjcx02_t=cratio_t*cjcx02;


    //External b-c diode saturation currents
    //ibcxs_t       = ibcxs*exp(zetabcxt*ln_qtt0+vgc/VT*(qtt0-1));


    //Constant external series resistances
    rcx_t   = rcx*exp(zetarcx*ln_qtt0);
    rbx_t   = rbx*exp(zetarbx*ln_qtt0);
    re_t    = re*exp(zetare*ln_qtt0);

    //Forward transit time in substrate transistor
    tsf_t   = tsf*exp((zetacx-1.0)*ln_qtt0);

    //Capacitance for c-s junction
    `TMPHICJ(cjs0,vds,zs,vpts,0,vgsc0,cjs0_t,vds_t,vpts_t)
    /*Peripheral s-c capacitance
     * Note, thermal update only required for vds > 0
     * Save computional effort otherwise
     */
    if (vdsp > 0) begin
        `TMPHICJ(cscp0,vdsp,zsp,vptsp,0,vgsc0,cscp0_t,vdsp_t,vptsp_t)
    end else begin
        // Avoid uninitialized variables
        cscp0_t = cscp0;
        vdsp_t = vdsp;
        vptsp_t = vptsp;
    end

    ahjei_t = ahjei*exp(zetahjei*ln_qtt0);
    hjei0_t = hjei*exp(dvgbe/VT*(exp(zetavgbe*ln(qtt0))-1));
    hf0_t   = hf0*exp(dvgbe/VT*(qtt0-1));
    if (flcomp >= 2.3) begin
        hfe_t   = hfe*exp((vgb-vge)/VT*(qtt0-1));
        hfc_t   = hfc*exp((vgb-vgc)/VT*(qtt0-1));
    end else begin
        hfe_t    = hfe;
        hfc_t    = hfc;
    end

    rth_t    = rth*exp(zetarth*ln_qtt0)*(1+alrth*dT);

end     //of Thermal_update_with_self_heating


begin : Model_evaluation

    //Intrinsic transistor
    //Internal base currents across b-e junction
    `HICDIO(ibeis,ibeis_t,mbei,Vbiei,ibei)
    `HICDIO(ireis,ireis_t,mrei,Vbiei,irei)

    //HICCR: begin

    //Inverse of low-field internal collector resistance: needed in HICICK
    Orci0_t = 1.0/rci0_t;

    //Initialization
    //Transfer current, minority charges and transit times

    Tr      = tr;
    VT_f    = mcf*VT;
    i_0f    = c10_t * limexp(Vbiei/VT_f);
    i_0r    = c10_t * limexp(Vbici/VT);

    //Internal b-e and b-c junction capacitances and charges
    //`QJMODF(cjei0_t,vdei_t,zei,ajei_t,V(br_biei),Qjei)
    //Cjei    = ddx(Qjei,V(bi));
    `QJMODF(cjei0_t,vdei_t,zei,ajei_t,Vbiei,Cjei,Qjei)
    if (ahjei == 0.0) begin
        hjei_vbe = hjei;
    end else begin
        //vendhjei = vdei_t*(1.0-exp(-ln(ajei_t)/z_h));
        vj = (vdei_t-Vbiei)/(rhjei*VT);
        vj = vdei_t-rhjei*VT*(vj+sqrt(vj*vj+`DFa_fj))*0.5;
        vj = (vj-VT)/VT;
        vj = VT*(1.0+(vj+sqrt(vj*vj+`DFa_fj))*0.5);
        vj_z = (1.0-exp(zei*ln(1.0-vj/vdei_t)))*ahjei_t;
        hjei_vbe = hjei0_t*(exp(vj_z)-1.0)/vj_z;
    end



    //`HICJQ(cjci0_t,vdci_t,zci,vptci_t,V(br_bici),Qjci)
    //Cjci    = ddx(Qjci,V(bi));
    `HICJQ(cjci0_t,vdci_t,zci,vptci_t,Vbici,Cjci,Qjci)

    //Hole charge at low bias
    a_bpt   = 0.05;
    Q_0     = qp0_t + hjei_vbe*Qjei + hjci*Qjci;
    Q_bpt   = a_bpt*qp0_t;
    b_q     = Q_0/Q_bpt-1;
    Q_0     = Q_bpt*(1+(b_q +sqrt(b_q*b_q+1.921812))/2);

    //Transit time calculation at low current density
    if(cjci0_t > 0.0) begin : CJMODF
        real cV_f,cv_e,cs_q,cs_q2,cv_j,cdvj_dv;
        cV_f    = vdci_t*(1.0-exp(-ln(2.4)/zci));
        cv_e    = (cV_f-Vbici)/VT;
        cs_q    = sqrt(cv_e*cv_e+1.921812);
        cs_q2   = (cv_e+cs_q)*0.5;
        cv_j    = cV_f-VT*cs_q2;
        cdvj_dv = cs_q2/cs_q;
        Cjcit   = cjci0_t*exp(-zci*ln(1.0-cv_j/vdci_t))*cdvj_dv+2.4*cjci0_t*(1.0-cdvj_dv);
    end else begin
        Cjcit   = 0.0;
    end
    if(Cjcit > 0.0) begin
        cc      = cjci0_t/Cjcit;
    end else begin
        cc      = 1.0;
    end
    T_f0    = t0_t+dt0h*(cc-1.0)+tbvl*(1/cc-1.0);

    //Effective collector voltage
    vc      = Vciei-vces_t;

    //Critical current for onset of high-current effects
    begin : HICICK
        Ovpt    = 1.0/vpt;
        a       = vc/VT;
        d1      = a-1;
        vceff   = (1.0+((d1+sqrt(d1*d1+1.921812))/2))*VT;
        // a       = vceff/vlim_t;
        // ick     = vceff*Orci0_t/sqrt(1.0+a*a);
        // ICKa    = (vceff-vlim_t)*Ovpt;
        // ick     = ick*(1.0+0.5*(ICKa+sqrt(ICKa*ICKa+1.0e-3)));

        a1       = vceff/vlim_t;
        a11      = vceff*Orci0_t;
        Odelck   = 1/delck;
        ick1     = exp(Odelck*ln(1+exp(delck*ln(a1))));
        ick2     = a11/ick1;
        ICKa     = (vceff-vlim_t)*Ovpt;
        ick      = ick2*(1.0+0.5*(ICKa+sqrt(ICKa*ICKa+aick)));

    end

    //Initial formulation of forward and reverse component of transfer current
    Q_p     = Q_0;
    if (T_f0 > 0.0 || Tr > 0.0) begin
        A       = 0.5*Q_0;
        Q_p     = A+sqrt(A*A+T_f0*i_0f+Tr*i_0r);
    end
    I_Tf1   =i_0f/Q_p;
    a_h     = Oich*I_Tf1;
    itf     = I_Tf1*(1.0+a_h);
    itr     = i_0r/Q_p;

    //Initial formulation of forward transit time, diffusion, GICCR and excess b-c charge
    Q_bf    = 0.0;
    Tf      = T_f0;
    Qf      = T_f0*itf;
    `HICQFF(itf,ick,Tf,Qf,T_fT,Q_fT,Q_bf)

    //Initial formulation of reverse diffusion charge
    Qr      = Tr*itr;

    //Preparation for iteration to get total hole charge and related variables
    l_it    = 0;
    if(Qf > `RTOLC*Q_p || a_h > `RTOLC) begin
        //Iteration for Q_pT is required for improved initial solution
        Qf      = sqrt(T_f0*itf*Q_fT);
        Q_pT    = Q_0+Qf+Qr;
        d_Q     = Q_pT;
        while (abs(d_Q) >= test(`RTOLC,abs(Q_pT)) && l_it <= `l_itmax) begin
            d_Q0    = d_Q;
            I_Tf1   = i_0f/Q_pT;
            a_h     = Oich*I_Tf1;
            itf     = I_Tf1*(1.0+a_h);
            itr     = i_0r/Q_pT;
            Tf      = T_f0;
            Qf      = T_f0*itf;
            `HICQFF(itf,ick,Tf,Qf,T_fT,Q_fT,Q_bf)
            Qr      = Tr*itr;
            if(Oich == 0.0) begin
                a       = 1.0+(T_fT*itf+Qr)/Q_pT;
            end else begin
                a       = 1.0+(T_fT*I_Tf1*(1.0+2.0*a_h)+Qr)/Q_pT;
            end
            d_Q     = -(Q_pT-(Q_0+Q_fT+Qr))/a;
            //Limit maximum change of Q_pT
            a       = abs(0.3*Q_pT);
            if(abs(d_Q) > a) begin
                if (d_Q>=0) begin
                    d_Q     = a;
                end else begin
                    d_Q     = -a;
                end
            end
            Q_pT    = Q_pT+d_Q;
            l_it    = l_it+1;
        end //while

        I_Tf1   = i_0f/Q_pT;
        a_h     = Oich*I_Tf1;
        itf     = I_Tf1*(1.0+a_h);
        itr     = i_0r/Q_pT;

        //Final transit times, charges and transport current components
        Tf      = T_f0;
        Qf      = T_f0*itf;
        `HICQFF(itf,ick,Tf,Qf,T_fT,Q_fT,Q_bf)
        Qr      = Tr*itr;

    end //if

    //NQS effect implemented with LCR networks
    //Once the delay in ITF is considered, IT_NQS is calculated afterwards

    it      = itf-itr;

    //Diffusion charges for further use
    Qdei    = Qf;
    Qdci    = Qr;


    //High-frequency emitter current crowding (lateral NQS)
    Cdei    = T_f0*itf/VT;
    Cdci    = tr*itr/VT;
    Crbi    = fcrbi*(Cjei+Cjci+Cdei+Cdci);
    qrbi    = Crbi*V(br_bpbi_v);

    // qrbi	= fcrbi*(Qjei+Qjci+Qdei+Qdci);

    //HICCR: end

    //Internal base current across b-c junction
    `HICDIO(ibcis,ibcis_t,mbci,Vbici,ibci)

    //Avalanche current
    if (use_aval == 1) begin : HICAVL
        real v_bord,v_q,U0,av,avl;
        v_bord  = vdci_t-Vbici;
        if (v_bord > 0) begin
            v_q     = qavl_t/Cjci;
            U0      = qavl_t/cjci0_t;
            if(v_bord > U0) begin
                av      = favl_t*exp(-v_q/U0);
                avl     = av*(U0+(1.0+v_q/U0)*(v_bord-U0));
            end else begin
                avl     = favl_t*v_bord*exp(-v_q/v_bord);
            end
            /* This model turns strong avalanche on. The parameter kavl can turn this
            * model extension off (kavl = 0). Although this is numerically stable, a
            * conditional statement is applied in order to reduce the numerical over-
            * head for simulations without the new model.
            */
            if (kavl > 0) begin : HICAVLHIGH
                real denom,sq_smooth,hl;
                denom = 1-kavl_t*avl;
                // Avoid denom < 0 using a smoothing function
                sq_smooth = sqrt(denom*denom+0.01);
                hl = 0.5*(denom+sq_smooth);
                iavl    = itf*avl/hl;
            end else begin
                iavl    = itf*avl;
            end
        end else begin
            iavl = 0.0;
        end
    end
    // Note that iavl = 0.0 is already set in the initialization block for use_aval == 0

    //Excess base current from recombination at the b-c barrier
    ibh_rec = Q_bf*Otbhrec;

    //Internal base resistance
    if(rbi0_t > 0.0) begin : HICRBI
        real Qz_nom,f_QR,ETA,Qz0,fQz;
        // Consideration of conductivity modulation
        // To avoid Convergence problem hyperbolic smoothing used
        f_QR    = (1+fdqr0)*qp0_t;
        Qz0     = Qjei+Qjci+Qf;
        Qz_nom  = 1+Qz0/f_QR;
        fQz     = 0.5*(Qz_nom+sqrt(Qz_nom*Qz_nom+0.01));
        rbi     = rbi0_t/fQz;
        // Consideration of emitter current crowding
        if( ibei > 0.0) begin
            ETA     = rbi*ibei*fgeo/VT;
            if(ETA < 1.0e-6) begin
                rbi     = rbi*(1.0-0.5*ETA);
            end else begin
                rbi     = rbi*ln(1.0+ETA)/ETA;
            end
        end
        // Consideration of peripheral charge
        if(Qf > 0.0) begin
            rbi     = rbi*(Qjei+Qf*fqi)/(Qjei+Qf);
        end
    end else begin
        rbi     = 0.0;
    end

    //Base currents across peripheral b-e junction
    `HICDIO(ibeps,ibeps_t,mbep,Vbpei,ibep)
    `HICDIO(ireps,ireps_t,mrep,Vbpei,irep)

    //Peripheral b-e junction capacitance and charge
    `QJMODF(cjep0_t,vdep_t,zep,ajep_t,Vbpei,Cjep,Qjep)

    //Tunneling current
    if (ibets > 0 && (Vbpei <0.0 || Vbiei < 0.0)) begin : HICTUN
        real pocce,czz;
        if(tunode==1 && cjep0_t > 0.0 && vdep_t >0.0) begin
            pocce   = exp((1-1/zep)*ln(Cjep/cjep0_t));
            czz     = -(Vbpei/vdep_t)*ibets_t*pocce;
            ibet    = czz*exp(-abet_t/pocce);
        end else if (tunode==0 && cjei0_t > 0.0 && vdei_t >0.0) begin
            pocce   = exp((1-1/zei)*ln(Cjei/cjei0_t));
            czz     = -(Vbiei/vdei_t)*ibets_t*pocce;
            ibet    = czz*exp(-abet_t/pocce);
        end else begin
            ibet    = 0.0;
        end
    end else begin
        ibet    = 0.0;
    end


    //Depletion capacitance and charge at peripheral b-c junction (bp,ci)
    `HICJQ(cjcx02_t,vdcx_t,zcx,vptcx_t,Vbpci,CjCx_ii,qjcx0_t_ii)

    //Base currents across peripheral b-c junction (bp,ci)
    `HICDIO(ibcxs,ibcxs_t,mbcx,Vbpci,ijbcx)

    //Depletion capacitance and charge at external b-c junction (b,ci)
    `HICJQ(cjcx01_t,vdcx_t,zcx,vptcx_t,Vbci,CjCx_i,qjcx0_t_i)

    //Depletion substrate capacitance and charge at s-c junction (si,ci)
    `HICJQ(cjs0_t,vds_t,zs,vpts_t,Vsici,Cjs,Qjs)
    /* Peripheral substrate capacitance and charge at s-c junction (s,c)
     * Bias dependent only if vdsp > 0
     */
    if (vdsp > 0) begin
        `HICJQ(cscp0_t,vdsp_t,zsp,vptsp_t,Vsc,Cscp,Qscp)
    end else begin
        // Constant, temperature independent capacitance
        Cscp = cscp0;
        Qscp = cscp0*Vsc;
    end

    //Parasitic substrate transistor transfer current and diffusion charge
    if(itss > 0.0) begin : Sub_Transfer
        HSUM    = msf*VT;
        HSa     = limexp(Vbpci/HSUM);
        HSb     = limexp(Vsici/HSUM);
        HSI_Tsu = itss_t*(HSa-HSb);
        if(tsf > 0.0) begin
            Qdsu    = tsf_t*itss_t*HSa;
        end else begin
            Qdsu    = 0.0;
        end
    end else begin
        HSI_Tsu = 0.0;
        Qdsu    = 0.0;
    end

    // Current gain computation for correlated noise implementation
    if (ibei > 0.0) begin
        betadc=it/ibei;
    end else begin
        betadc=0.0;
    end

    //Diode current for s-c junction (si,ci)
    `HICDIO(iscs,iscs_t,msc,Vsici,ijsc)

    //Self-heating calculation
    if (flsh == 1 && rth >= `MIN_R) begin
        pterm   =  Vciei*it + (vdci_t-Vbici)*iavl;
    end else if (flsh == 2 && rth >= `MIN_R) begin
        pterm   =  Vciei*it + (vdci_t-Vbici)*iavl + ibei*Vbiei + ibci*Vbici + ibep*Vbpei + ijbcx*Vbpci + ijsc*Vsici;
        if (rbi >= `MIN_R) begin
            pterm   = pterm + V(br_bpbi_i)*V(br_bpbi_i)/rbi;
        end
        if (re_t >= `MIN_R) begin
            pterm   = pterm + V(br_eie_i)*V(br_eie_i)/re_t;
        end
        if (rcx_t >= `MIN_R) begin
            pterm   = pterm + V(br_cic_i)*V(br_cic_i)/rcx_t;
        end
        if (rbx_t >= `MIN_R) begin
            pterm   = pterm + V(br_bbp_i)*V(br_bbp_i)/rbx_t;
        end
    end

    Itxf	= itf;
    Qdeix	= Qdei;
    // Excess Phase calculation

    if ((flnqs != 0 || flcomp == 0.0 || flcomp == 2.1) && Tf != 0 && (alit > 0 || alqf > 0)) begin
        Vxf1	= V(br_bxf1);
        Vxf2	= V(br_bxf2);

        Ixf1	=  (Vxf2-itf)/Tf*t0;
        Ixf2	=  (Vxf2-Vxf1)/Tf*t0;
        Qxf1	=  alit*Vxf1*t0;
        Qxf2	=  alit*Vxf2/3*t0;
        Itxf	=  Vxf2;

        Vxf	= V(br_bxf);          //for RC nw
        fact  = t0/Tf;                 //for RC nw
        Ixf   = (Vxf - Qdei)*fact;     //for RC nw
        Qxf   = alqf*Vxf*t0;           //for RC nw
        Qdeix = Vxf;                   //for RC nw
    end else begin
        Ixf1	=  V(br_bxf1);
        Ixf2	=  V(br_bxf2);
        Qxf1	=  0;
        Qxf2	=  0;

        Ixf   = V(br_bxf);
        Qxf   = 0;
    end

end     //of Model_evaluation

begin : Load_sources

    I(br_biei)      <+ `Gmin*V(br_biei);
    I(br_bici)      <+ `Gmin*V(br_bici);
    I(br_ciei)	    <+ `Gmin*V(br_ciei);

    I(br_bci)       <+ ddt(type*qjcx0_t_i);
    I(br_bci)       <+ ddt(cbcpar1*V(br_bci));
    I(br_bpci)      <+ ddt(cbcpar2*V(br_bpci));
    if (rbx >= `MIN_R) begin
        I(br_bbp_i)     <+ V(br_bbp_i)/rbx_t;
    end else begin
        V(br_bbp_v)     <+ 0.0;
    end
    if(rbi0 >= `MIN_R) begin
        I(br_bpbi_i)    <+ V(br_bpbi_i)/rbi;
        I(br_bpbi_i)    <+ ddt(qrbi);
    end else begin
        V(br_bpbi_v)    <+ 0.0;
    end
    if (tunode==1.0) begin
        I(br_bpei)      <+ -type*ibet;
    end else begin
        I(br_biei)      <+ -type*ibet;
    end
    I(br_bpei)      <+ type*ibep;
    I(br_bpei)      <+ type*irep;
    I(br_bpei)      <+ ddt(type*Qjep);
    I(br_biei)      <+ type*ibei;
    I(br_biei)      <+ type*irei;
    I(br_biei)      <+ type*ibh_rec;
    I(br_biei)      <+ ddt(type*(Qdeix+Qjei));
    I(br_bpsi)      <+ type*HSI_Tsu;
    I(br_bpci)      <+ type*ijbcx;
    I(br_bpci)      <+ ddt(type*(qjcx0_t_ii+Qdsu));
    I(br_be)        <+ ddt(cbepar1*V(br_be));
    I(br_bpe)       <+ ddt(cbepar2*V(br_bpe));
    I(br_bici)      <+ type*(ibci-iavl);
    I(br_bici)      <+ ddt(type*(Qdci+Qjci));
    I(br_sici)      <+ type*ijsc;
    I(br_sici)      <+ ddt(type*Qjs);
    I(br_sc)        <+ ddt(type*Qscp);
    I(br_ciei)      <+ type*Itxf;
    I(br_eici)      <+ type*itr;
    if (rcx >= `MIN_R) begin
        I(br_cic_i)     <+ V(br_cic_i)/rcx_t;
    end else begin
        V(br_cic_v)     <+ 0.0;
    end
    if (re >= `MIN_R) begin
        I(br_eie_i)     <+ V(br_eie_i)/re_t;
    end else begin
        V(br_eie_v)     <+ 0.0;
    end
    if(rsu >= `MIN_R) begin
        I(br_sis_i)     <+ V(br_sis_i)/rsu;
        I(br_sis_i)     <+ ddt(csu*V(br_sis_i));
    end else begin
        V(br_sis_v)     <+ 0.0;
    end

    // Following code is an intermediate solution (if branch contribution is not supported):
    // ******************************************
    //if(flsh == 0 || rth < `MIN_R) begin
    //      I(br_sht)       <+ V(br_sht)/`MIN_R;
    //end else begin
    //      I(br_sht)       <+ V(br_sht)/rth_t-pterm;
    //      I(br_sht)       <+ ddt(cth*V(br_sht));
    //end

    // ******************************************

    // For simulators having no problem with V(br_sht) <+ 0.0
    // with external thermal node, following code may be used.
    // Note that external thermal node should remain accessible
    // even without self-heating.
    // ********************************************
    if(flsh == 0 || rth < `MIN_R) begin
        V(br_sht)       <+ 0.0;
    end else begin
        I(br_sht)       <+ V(br_sht)/rth_t-pterm;
        I(br_sht)       <+ ddt(cth*V(br_sht));
    end
    // ********************************************

    // NQS effect
    I(br_bxf1) <+ Ixf1;
    I(br_cxf1) <+ ddt(Qxf1);
    I(br_bxf2) <+ Ixf2;
    I(br_cxf2) <+ ddt(Qxf2);

    I(br_bxf) <+  Ixf;         //for RC nw
    I(br_cxf) <+  ddt(Qxf);    //for RC nw

end //of Load_sources


`NOISE begin : Noise_sources

    //Thermal noise
    fourkt  = 4.0 * `P_K * Tdev;
    if(rbx >= `MIN_R) begin
        I(br_bbp_i)     <+ white_noise(fourkt/rbx_t,    "rbx");
    end
    if(rbi0 >= `MIN_R) begin
        I(br_bpbi_i)    <+ white_noise(fourkt/rbi,      "rbi");
    end
    if(rcx >= `MIN_R) begin
        I(br_cic_i)     <+ white_noise(fourkt/rcx_t,    "rcx");
    end
    if(re >= `MIN_R) begin
        I(br_eie_i)     <+ white_noise(fourkt/re_t,     "re");
    end
    if(rsu >= `MIN_R) begin
        I(br_sis_i)     <+ white_noise(fourkt/rsu,      "rsu");
    end

    //Flicker noise : Fully correlated between the perimeter and internal base-node
    flicker_Pwr     = kf*pow(abs(ibei+ibep),af);
    if (cfbe == -1) begin
        I(br_biei)      <+ flicker_noise(flicker_Pwr,1.0, "flicker");
    end else begin
        I(br_bpei)      <+ flicker_noise(flicker_Pwr,1.0, "flicker");
    end

    if (re >= `MIN_R) begin
        i_re     = V(br_eie_i)/re_t;
        flicker_Pwr     = kfre*pow(abs(i_re),afre);
        I(br_eie_i)     <+ flicker_noise(flicker_Pwr,1.0, "flicker_re");
    end

    //Shot noise

    twoq    = 2.0 * `P_Q;
    I(br_cibi)      <+ white_noise(twoq*iavl,       "iavl");

    I(br_bici)      <+ white_noise(twoq*abs(ibci),  "ibci");

    I(br_bpei)      <+ white_noise(twoq*abs(ibep),  "ibep");

    I(br_bpci)      <+ white_noise(twoq*abs(ijbcx), "ijbcx");

    I(br_sici)      <+ white_noise(twoq*abs(ijsc),  "ijsc");

    // Code section for correlated noise

    if ( flcono==1 && (alit > 0 && alqf > 0)) begin

    // parameter definition
        n_w = 1;
        n_1 = Tf*alit;
        sqrt_n2 = betadc*(2*alqf-alit*alit);

        if (sqrt_n2 > 0.0) begin
            n_2 = Tf*sqrt(sqrt_n2);
        end else begin
            n_2 = 0;
        end


    // realization  of modified base shot noise source I1(bi,ei)
        I(b_n1)  <+ white_noise(2*`P_Q*abs(ibei),"ibei");
        I(b_n1)  <+ -V(b_n1);
        I(bi,ei) <+ V(b_n1)+n_2/n_w*ddt(n_w*V(b_n1));

    // realization of controlled base noise source I2(bi,ei)

        I(bi,ei) <+ n_1/n_w*ddt(n_w*V(b_n2));

    // realization of modified collector shot noise source I(ci,ei) (uncontrolled)

        I(b_n2)  <+ white_noise(2*`P_Q*abs(it),"it");
        I(b_n2)  <+ -V(b_n2);
        I(ci,ei) <+ V(b_n2);


    //  end  "Correlated noise in BJT"


    end else begin

    // Applying the base & collector shot noise sources to appropriate branches

        I(br_ciei)  <+ white_noise(twoq*abs(it),         "it");
        I(br_biei)  <+ white_noise(twoq*abs(ibei),       "ibei");
        I(b_n1)     <+ V(b_n1);
        I(b_n2)     <+ V(b_n2);

    end // end of flcono section

end     //of Noise_sources

// Operating point calculations
`ifdef CALC_OP
    `ifdef OP_STATIC
    if (analysis("static")) begin: OPERATING_POINT
    `else
    begin: OPERATING_POINT
    `endif
        real gPIi, gPIx, gBt;
        real gMUi, gMUx, gAVL;
        real gOi;
        real CdEi_ddx, CdCi_ddx, CdS_ddx;

        IB   = I(<b>);
        IC   = I(<c>);
        IS   = I(<s>);
        IAVL = type*iavl;

        VBE = V(b,e);
        VBC = V(b,c);
        VCE = V(c,e);
        VSC = V(s,c);

        if (IB != 0) begin
            BETADC = IC/IB;
        end else begin
            BETADC = 0;
        end

        GMi    = type*ddx(it,V(bi))+`Gmin;
        GMS    = -type*ddx(HSI_Tsu,V(ci))+`Gmin;

        gPIi = type*ddx(ibei,V(bi))+type*ddx(irei,V(bi))+`Gmin;
        gPIx = type*ddx(ibep,V(bp))+type*ddx(irep,V(bp))+`Gmin;

        if (tunode == 1) begin
            gBt = type*ddx(ibet,V(bp));

            RPIi = 1.0/gPIi;
            RPIx = 1.0/(gPIx-gBt);
        end else begin
            gBt = type*ddx(ibet,V(bi));

            RPIi = 1.0/(gPIi-gBt);
            RPIx = 1.0/gPIx;
        end

        gMUi = -type*ddx(ibci, V(ci))+`Gmin;
        gMUx = -type*ddx(ijbcx,V(ci))+`Gmin;
        gAVL = type*ddx(iavl, V(ci))+`Gmin;

        RMUi = 1/(gMUi-gAVL);
        RMUx = 1/gMUx;

        gOi = type*ddx(it,V(ci));
        ROi = 1/(gOi+gAVL);

        CdEi_ddx = -type*ddx(Qdei,V(ei));
        CdCi_ddx = -type*ddx(Qdci,V(ci));

        CPIi = Cjei+CdEi_ddx;
        CPIx = Cjep+cbepar;

        CdS_ddx = -type*ddx(Qdsu,V(ci));

        CMUi = Cjci+CdCi_ddx;
        CMUx = CjCx_i+CjCx_ii+cbcpar+CdS_ddx;

        CCS = Cjs+Cscp;

        rb  = rbi+rbx_t;

        if (gPIi+gPIx > 0.0) begin
            BETAAC = GMi/(gPIi+gPIx);
        end else begin
            BETAAC = 0.0;
        end

        CRBI = Crbi;
        TF   = Tf;

        FT = GMi/(2*`M_PI*(CPIi+CPIx+CMUi+CMUx+(rcx_t+re_t+(re_t+rb)/BETAAC)*GMi*(CMUi+CMUx)));

        TK = Tdev;
        DTSH = V(br_sht);
    end
`endif

end //analog
endmodule