ZP3 Board Tracking

Motivation behind this document is as we assemble boards we would like to keep track of their lifespan

First board to be powered up, marked on the label on the back with silver and black sharpie. Was check for shorts with DMM. 236k ohm VBATT input. 3V3 to GND 26.2k ohms. 5V to GND 1.1k ohms. Board kept reaching current limit at 1 A constantly as current limit. Initially powered on with 7 V then upped to 10 V then upped to 20 V for the following oscope captures. Board did not smoke at all, but the 5V and 3V3 power did not turn on. Oscilloscope captures of our input voltage after the power filter, 5V switch node and 5V output node are included below!

V_out

So it seems the post power filter net has 1V ripple at roughly 200microseconds. The 5V SW node has 1V ripple at 8microseconds or 125kHz (as expected from the buck datasheet). 5V output is nearly zero. The power supply is also the culprit and was probed separately and has no noise within our scope range.

Buck Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max5033.pdf

I cannot find any issues in our application and suspect IC solder job. Ethan is inspecting. Reflowed the IC. Confirmed pinout is correct. No change in performance. Soldering photos were taken in discord and may be inserted below.

The table below is for keeping track of the Status of the Zeropilot 3 primary boards being assembled

ZP3 Primary Num	Status

ZP3 Primary Num	Status
ZP3-1	2023/07/01 MCU pins fixed, all components on the top of board assembled Molex connectors soldered, right XT60 attached Board plugged into power and LED turns on (working) Test code not flashed 2023/07/08 Blinking code flashed
ZP3-2	2023/07/01 MCU pins fixed, top side assembled, needs molex soldered on back side 2023/07/08 No more progress
ZP3-3	2023/07/01 MCU pins fixed, top side components assembled Molex connector not finished soldering, XT60 not soldered 2023/07/08 No more progress
ZP3-4	2023/07/01 All assembly finished (MCU pins fixed, all components attached, XT60 and molex attached) Tested all rails for shorts, no shorts found. When plugged into power LED isnt on, no smoking, minimal current draw (10mA approx) Test code not flashed 2023/07/08 Found multiple flipped diodes, resoldered one, 2 larger diodes need to be flipped Not tested yet 2023/07/27 Flipped the diodes, plugged into power, LEDs turn on Just needs to be code tested (flash blinking LED script to it)
ZP3-5	2023/07/01 MCU pins still need fixing, one pin badly bent, many pins still badly bridged All other top components assembled on board 2023/07/08 MCU removed from board, cleaned up pads and resoldered new MCU on to board Some pins need a bit more solder

The table below is for keeping track of the Status of the Zeropilot 3 interface boards being assembled

ZP3 Interface Num	Status

ZP3 Interface Num	Status
ZP3-1	2023/07/01 Assembly finished (all top side components soldered, molex attached, all pin headers soldered) Missing MOSFETs and C1-C4 on top side, missing ST-LINK connector Needs to be tested 2023/07/08 No progress
ZP3-2	2023/07/01 Top side assembled (All components attached, molex attached) Missing top side MOSFETs Headers not soldered 2023/07/08 No progress
ZP3-3	2023/07/01 Top side assembled (All components attached, molex attached) Missing top side MOSFETs Headers not soldered 2023/07/08 No progress
ZP3-4	2023/07/01 Not started 2023/07/08 No progress
ZP3-5	2023/07/01 Not started 2023/07/08 No progress