pcb-toolkit

Rust library for PCB design calculations — impedance, current capacity, via properties, and more.

Part of the pcb-toolkit workspace.

Usage

[dependencies]
pcb-toolkit = "0.1"

use pcb_toolkit::impedance::microstrip::{self, MicrostripInput};

let result = microstrip::calculate(&MicrostripInput {
    width: 10.0,       // mils
    height: 5.0,       // mils
    thickness: 1.4,    // mils (1 oz copper)
    er: 4.6,           // FR-4
    frequency: 0.0,    // Hz (0 = static)
}).unwrap();

println!("Zo = {:.2} Ohms", result.zo);
println!("Er_eff = {:.4}", result.er_eff);
println!("Tpd = {:.2} ps/in", result.tpd_ps_per_in);

All public functions return Result<T, CalcError>. Negative dimensions, out-of-range dielectric constants, and unknown materials are rejected with descriptive errors.

Modules

Module	Description	Status
`impedance::microstrip`	Microstrip impedance (Hammerstad-Jensen 1980)	Implemented
`impedance::stripline`	Stripline impedance (Cohn / Wadell)	Planned
`impedance::embedded`	Embedded microstrip (Brooks)	Planned
`impedance::coplanar`	Coplanar waveguide (Wadell)	Planned
`differential`	Differential pair impedance (6 topologies)	Types defined
`via`	Via parasitics: L, C, Z, resonance, DC R, thermal R	Planned
`current`	Conductor current capacity (IPC-2221A / IPC-2152)	Planned
`fusing`	Fusing current (Onderdonk equation)	Planned
`inductor`	Planar spiral inductors (Mohan/Wheeler)	Planned
`padstack`	Pad sizing (TH, BGA, routing)	Planned
`crosstalk`	Standalone crosstalk estimation	Planned
`ohms_law`	V=IR, LED bias, attenuators, series/parallel	Planned
`reactance`	Xc, Xl, resonant frequency	Planned
`wavelength`	Signal wavelength in dielectric	Planned
`ppm`	PPM/Hz conversion, crystal load capacitor	Planned
`spacing`	IPC-2221C minimum conductor spacing	Planned

Supporting Infrastructure

materials — 25 built-in substrate materials (FR-4, Rogers, Isola, Getek, Teflon) with Er, Tg, and roughness correction. Case-insensitive lookup.
copper — Copper weight to thickness conversion (0.25 oz through 5 oz), plating thickness, etch factor cross-section correction.
units — Conversion between user-facing units and canonical internal units (mils, Hz, Farads, Henries, Celsius).
constants — Physical constants (speed of light, copper resistivity, etc.).
tables — Linear interpolation for lookup tables.

Design

f64 everywhere. No arbitrary-precision or unit-of-measure crates.
Canonical internal units. Mils for length, Hz for frequency. Conversion at the API boundary.
Minimal dependencies. thiserror for errors, serde for serialization.

License