Design Review 8/5/20:

• Blank is permanently disabled. That's probably OK. What will the power-up state of the PWM controller and the H-Bridge drivers be? Please ensure that the motors cannot power up when the board is initially powered.
• Somehow need to label the silkscreen the strings "eVOLVER" "Motor Board" "Rev A" and "edf.bu.edu" in a legible size. Ideally on the front. Good luck!

Design Review 8/3/20:

• Please actually make these changes to the copper area settings:
  • adjust the copper fill settings for GND to: Clearance=0.007 Minimum width=0.007 Antipad clearance=0.01 spoke width=0.01
• Why is there a note "Omit all 0603 Footprints" on the back silkscreen?

Design Review 7/30/20:

• I think the pin assignments on the new package for H-bridge are wrong. This needs to be fixed before reviewing much more of the layout.
• Worried about narrow neck of +24V on In2 near 3V3 pin.
• For the PMODE jumper I was thinking of 2x 0402 sites with a zero-ohm resistor on the BOM to connect it to GND. If you remove the big 3-pin header then there is room to wrap the +24V plane across the top which would help with the previous concern.
• ADC connector would need a GND to be useful, and maybe 3V3 too. It could be a 2mm pitch if that helps. We should really check with Brandon if he would ever use it.

Design Review 7/29/20:

• Just out of curiosity, why did you use the larger HTSSOP package instead of the smaller VQFN package?
• The ground plane is sliced up by the clearance around the thermal vias on the DRV chips. Proposed changes:
  • reduce the number of thermal vias to a 3x3 array. We are not running these chips near max power
  • adjust the copper fill settings for GND to: Clearance=0.007 Minimum width=0.007 Antipad clearance=0.01 spoke width=0.01
• There are several DRC errors "track near pad" in my Kicad 5.0.2
• DRV8876 recommends "bulk capacitance" on V(M). We should put at least an 0603 site or so on the board for this on +24V.
• C13 etc are supposed to be "low ESR" types. I couldn't find any data on ESR for this series (Murata GRM)
  • Maybe substitute 445-5932-1-ND
• For flexibility, connect PMODE on all drivers (together) to solder jumpers to VCC and GND, with a default connection to GND via zero ohm R
• Silkscreen text too small to be legible. I don't see a good fix for this, and I guess we treat the silkscreen (in PDF form) as an assembly drawing.