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Project: HomeAutomation

First in-wall switch board revision is a FAIL

The six-button switch for in-wall mounting that I wrote about in March (no update for quite some time!) has been designed, the board layed out and manufactured.

Today I wanted to populate the first board to have it handy while implementing the device firmware, however, I noticed that the main microcontroller (an AT90CAN128) does not fit the footprint on the PCBs...

QFP64 can come in more than one size, and while the IC is housed in a 14x14mm sized package, I chose a 12x12 mm one... Which doesn't fit.

Though I did check all the other footprints on the board before sending it to production, I just trusted the one on the MCU - perhaps thinking that "QFP64 means QFP64, what can possibly go wrong?".

On the positive side, though, the white soldermask (and black print on it) came out looking good, so I'll keep that for the next revision. And while it would work, I can as well make the pushbutton footprint a bit higher while I'm at it, and reduce the width on the ISP pads.