#pcb

Printed-circuit-board design maths as an API, computed locally and deterministically. The trace-width endpoint applies the IPC-2221 standard to find the minimum copper trace width for a current and an allowable temperature rise, A = (I/(k·ΔT^0.44))^(1/0.725) with k = 0.048 for outer layers and 0.024 for inner, returning the cross-section and the width in mils and millimetres for a given copper weight. The trace-resistance endpoint computes a trace's resistance from its width, length and copper thickness, R = ρ·L/(W·t), with the copper temperature coefficient, and — given a current — the voltage drop and power dissipation. The microstrip endpoint computes the characteristic impedance of a microstrip line by the Hammerstad model from the trace width, the dielectric height and the dielectric constant (about 4.5 for FR4), with the effective permittivity and propagation delay for controlled-impedance routing. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, hardware, embedded and PCB-design app developers, board-layout and signal-integrity tools, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is PCB design; for resistor colour codes use a resistor API and for general Ohm's-law maths an Ohm's-law API.

api.oanor.com/pcb-api