...

•  Fix diode silkscreen on the bottom of the board
•  Remove R1, replace R2 with a smaller value for more current into comparator
•  Q1 should have 1/2/4/6 and 4 swapped 
•  Ultra-fit and Dura-Clik connectors instead of Clik-Mates
•  Add passthrough for relay sense line (shorted when relay is closed, open circuit when relay is open)
•  Fix voltage drop with MOSFET stages
•  Add hysteresis to avoid bouncing 
•  Add an NAND gate between negative input and comparator output
•  Try to increase voltage going into opto-isolator. Around 2V right now due to voltage division
•  Consider using non-tented vias or through hole test points. Some TPs were ripped off
  •  Also don't put TPs directly on a trace as if it falls off it takes the entire trace with it 

Rev 2 Retrospective

Overall, it worked well. Taiping Lireflowed one side using the reflow oven and did the other by hand. This seemed to be a good strategy, with only a reversed LED and non-functional relay requiring rework.

• Required rework to test with 12V - needed to modify resistor dividers
• Connectors are great and really useful when testing a board
• 0 ohm resistors are great for disconnecting things and changing resistor values
• Resistor dividers need to be biased towards IN- (increase R13)
  • Need to tune values - greatly influences time precharge takes
• Need to add a decoupling/bulk cap between HV relay 12V and GND to reduce ripple - 10uF seems to work fine