REFERENCE DESIGNS

Open hardware, with the files to prove it.

887 published boards whose schematic and layout source is public — KiCad, EAGLE, Altium and EasyEDA projects you can read, fork and build on. Every entry links to the original repository and names its licence.

Boards indexed

887

With a design page

887

KiCad projects

405

555 Timer 1sec to 100sec

by jonathanrjpereira

⌛ Control a relay connected device for a period of 1 to 100 seconds using a 555

8 2GPL-3.0

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Every project listed here belongs to its author and is linked to its original repository. Licences are read from the repository metadata and summarised for convenience — check the licence file in the project itself before you manufacture or redistribute a design. ProtoFlow does not host, mirror or verify these files. Index last rebuilt 2026-09-21.

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