I built the latest version of the EVSE variant logic board two days ago. What a pain in the ass that turned out to be. I only just got everything working (I think).

I discovered quite a few issues:

1. DirtyPCBs' soldermask aperture doesn't always put soldermask between pins. Particularly on fine pitch parts, like TSSOP6 MOSFET arrays. This causes painful games of "find the short." On the other hand, OSHPark doesn't e-test. This can also cause painful games of "find the short" (though not frequently). Pick your poison.

2. I think that the pilot generator was causing transients on the power. The secondary MOSFET pair for each has a resistor from source to gate to hold the MOSFET open, and then a resistor from the gate to the primary MOSFET to close the MOSFET when desired. The initial values were 10k for the hold-open resistor and 0 for the close resistor. It turns out that resistors cause things to slow down. Having 0 for the closing resistor and 10k for the opening one meant that both MOSFETs were turned on very, very briefly before the opening resistor could raise the voltage on the turning-off MOSFET's gate. The new values are 4.7k for the opening resistor (source to gate) and 10k for the closing resistor (gate to primary output). This appears to work perfectly, and the rise and fall times are still well inside of the 2 µS mandated by the spec.

3. Because of the power transients I was investigating the DC-DC converters. I switched to a new filter cap for this board and thought it was causing problems. In screwing with it, I made the +5 supply filter cap's negative connection get flaky.

4. It turns out that LM358 op amps don't like having high impedance loads when used as a comparator (that is, with no feedback). This caused the GFI circuit to not work. I tacked on a 20k impedance load on the output, but the next board design will have a 10k loading resistor.

All of that done, it appears to finally be working properly.