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First draft schematic

A project log for Time Circuits Timepiece

A practical-size, Back to the Future themed digital clock mimicking the "Present Time" portion of the DeLorean's time circuit displays.

stephen-holdawayStephen Holdaway 02/18/2017 at 05:190 Comments

Schematics with KiCad! Previously I've used Eagle, but as this was originally going to be a single 300mm x 40mm board, Eagle wasn't going to work with its restrictive board size limits. I'm currently deciding whether to have a few smaller boards or one large one. Smaller boards are easier to mask and etch by hand, and errors are less costly, so if I can route these display boards single sided I'll just etch them myself.

The plan for multiple display boards is this, where the IC icons represent which boards hold which driver chips:

By having driver chips only connected to segments on their own PCB, there's just five connections to make between each board (VCC, GND, DIN/DOUT, CLK, LOAD). The schematic is wired assuming this layout.

Design notes so far:

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