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References we reach for daily.

Working calculators, our file-preparation checklist, and the production guide we send to customers planning a build.

Download

The production guide, free.

A useful reference if you are planning electronic manufacturing: process limits, data requirements, and the decisions that drive cost. No form to fill in.

Download PDF Or read capabilities online
Macro view of a multilayer board showing copper surface-mount components and printed reference designators.

Engineering calculators

Quick maths, no spreadsheet.

Two of the calculations we run most often when reviewing a customer design. Everything happens in your browser — nothing is sent to us.

Calculator 01

PCB trace width

Minimum external trace width for a given current and temperature rise, per the IPC-2221 curve fit.

Enter values to calculate.

External layers, IPC-2221A. Internal traces need roughly twice the width. Treat as a starting point, not a substitute for thermal analysis.

Calculator 02

Ohm's law & power

Fill in any two values and the other two are derived, including dissipated power.

Enter any two values.

Need impedance, resistor colour codes, capacitance conversion or a voltage divider? Send us the parameters and we will run it as part of your design review — get in touch.

Checklist

Prepare files the way our CAM engineers read them.

Almost every avoidable delay in fabrication starts with ambiguous data. Ten minutes here saves a day later.

Send your data pack

Format

  • Gerber RS-274X, with the drill file in Excellon format
  • Avoid 274D — if unavoidable, include the aperture file
  • ODB++, Protel .PCB/.PCBDOC and Eagle .BRD also accepted
  • State your Eagle version to prevent conversion errors

Double-sided set

  • 2 track layers (top, bottom)
  • 2 mask layers (top, bottom)
  • Legend print (top, bottom)

Single-sided set

  • 1 track layer (top or bottom)
  • 1 mask layer, matching the track layer
  • Legend print (top, bottom or both)

Always include

  • Drill drawing with PTH, NPTH and slot sizes defined
  • Mechanical / routing / profile layer
  • NC drill file
  • Any special layers — gold tab, carbon, peel-off, paste

Two rules that save days

Name layers plainly. A readable layer name or a short readme means nobody has to guess which copper is which.

Never mirror a layer. A PCB is viewed top-down through the board. Text on the top side should read normally; text on the bottom side should read mirrored.