TRACE Boardviewer
View an Allegro .brd file for electronics repair
An Allegro .brd is a native PCB database. TRACE opens selected native layouts so you can find parts and pins, highlight nets and keep schematic PDFs beside the board. It is free and MIT-licensed. This guide explains what the current release reads and when to request an export instead.
Which Allegro versions does TRACE open?
The reader covers documented binary record layouts from 16.0 to 17.5. That range does not mean every database written by those versions is supported: unknown record types, unsupported layer codes and inconsistent records are refused with a diagnostic.
| Database layout | Evidence |
|---|---|
| 16.2, 16.4, 16.5, 16.6 and 17.2 | Selected real files checked; this is not complete coverage of all exports. |
| 16.0, 17.4 and 17.5 | Synthetic validation only. |
| Older 14.x/15.x and newer unsupported layouts | Recognized where possible, but not imported. Request a supported export. |
The .brd extension also belongs to EAGLE and several repair boardview formats. TRACE identifies the content. If it reports EAGLE or TestLink rather than Allegro, use the BRD identification guide.
What you can inspect
TRACE reads components, values, packages, pin labels, nets, pads and the board outline from the supported records. Search for a reference such as U1, select a net to see its connected pins, and switch between the top and mirrored bottom side. Drilled through pads appear on both sides.
Component bodies are estimated from their pads. Curved outlines are drawn as chords; custom pad shapes use their declared rectangular extents. Tracks, copper fills, general graphics and vias are omitted. Use the original design tool or its dedicated viewer when you need those details.
TRACE is a repair document viewer. It does not edit or save the native database, check design rules, or supply board files.
Open the board and attach its schematic
- Download TRACE 1.3.1. Windows x64 is portable; the Apple-silicon macOS and Linux x86-64 builds are experimental. Native acceptance run 37974058845 reported issues on both platforms; investigation is ongoing.
- Open the
.brdwith Ctrl+O (Cmd+O on a Mac), or drag it into TRACE. Read the import notice for that file's approximations and omissions. - Search parts and nets. Use the Documents tab to attach the schematic PDF and datasheets you already have.
- Search the PDF text and follow exact board reference links. For a scanned PDF, choose Recognize text for bundled English OCR; it works offline and can be cancelled.
- Add voltage or resistance notes to the relevant part or pin. The first-session guide explains document attachment, cross-probing and saved notes.
A screenshot of the shared board/schematic workflow is available on the demo page. Its openly licensed KiCad example is labelled with its source and the earlier app version; it is not an Allegro import example.
What to do when a native file will not open
Check the diagnostic first. Native databases are limited to 64 MiB, and unsupported versions, record types or footprint layer codes are refused. Renaming the file does not convert its contents.
If you can open the design in its original tool, request a GenCAD 1.4 export for TRACE. Otherwise ask the design owner for an export or use a viewer that supports that native version. TRACE cannot recover missing documentation from a PDF alone.
The full compatibility table and reader support notes give the exact current scope. A bug report is most useful with the named format, app version, size and diagnostic; attach only files you may share.
Free, local and available on three desktop platforms
The same reader is included in Windows, macOS and Linux builds. Board processing, PDF search, OCR and repair notes stay local. No account or telemetry is required, and support is optional.
Working with an Altium design instead? See the PcbDoc and SchDoc guide. For other tools and their stated capabilities, see the boardviewer comparison.
Product names identify file formats and programs. They are trademarks of their owners; TRACE is not affiliated with them.