PDB Rev 4 Improvements

What worked

• Forward reverse polarity

• High side switch circuits can be reused, but they can also be replaced with FETs or another IC - up to the designer

What didn't work

• footprints designed wrong

  • D9 (inverse polarity)

• 5V converter: IC couldn’t be assembled with hot air gun

  • Could be assembled with oven or hot plate - needs to be tested

  • Avoid QFN packages if alternatives available

• 17V converter:

  • Compensation circuit was missing (even from WEBENCH) - likely the reason why it won’t start

Things to test

• Reverse polarity on input

• Fix feedback resistors on 17V converter

Things to Update

• Add a small connector on buck converter outputs to make testing easier with loading

• Try replacing USB A 2.0 connector with a different, smaller connector (i.e. micro-USB - coordinate with firmware)

• Try finding a new CAN transceiver - current one is out of stock, there’s not many left in the bay

• Confirm with other subteams if ultrasonic sensors needed - remove if unnecessary

• Remove BMS from the PDB

Things to add

• Current sensing for each rail - VBAT, 5V, 17V, 24V (multiphase buck)

  • Coordinate with firmware and mech teams to see if this would be useful, might not need all rails to be measured

  • This could be easily implemented by selecting a good load switch - good load switches can offer lots of voltage/current monitoring, fault detection, overvoltage/overcurrent, etc.

• Power connectors for each output/motor +extras