Changes made to Rev

Owned by Logan Hartford
Last updated: Aug 10, 2023
2 min read

Schematic Changes:

R44 and R45 are 0603 and should be 0805
Change 0.1uF 10V to 50V for consistency (5V high side switched)
3.3k (r2) 0603 part number
There are 16V, 50V and 100V 1uF caps on the board
Make the current gain max out at 1.8V, change out the TVs diode for one that hopefully works,
In the firmware, the STM should shutdown the output when the voltage reaches 1.8V so it has a margin of error to shut down the output before it becomes dangerous to the stm
Should probably double the power rating on the current sense resistors for the 24V buck

  • Instead of changing the max voltage output to 1.8V, I’m going to leave it at 3V and add in a Zener diode with a current-limiting resistor. The current version did not work because the TVS diode did not have current limiting resistor

N-Ch fet description says 340mS instead of 340 mA
STM reset button footprint is wrong, shorts itself out
SHDN on CAN should have a test point
RST pin on microcontroller should have testpoint w label
Add clippy testpoints to all of the voltage rails
reduce the small terminal through hole size for better alignment
Both 5V rail ADC pins do not go to ADC capable pins
Current sens +/- pin name wrong
N-CH footprint is wrong
LED doens’t work
17V current sense should be supplier by 17V so it doesn’t blow up
Either combine the 5V rails or make sure all of the start up conditions are on the same 5V rail
Add in option to combine 5V rails through a 0 ohm R
Change terminals for input and output of bucks to new vertical connector

Layout Changes:

Add label to 3v3 led
Add polarity indicators to terminals
Add testpoint labels where convenient
RST pin on microcontroller should have testpoint w label
Changle 5V_1 plane on GND layer to 5V_2, so all start up conditions are on the same 5V rail
Remove thermal reliefs on very high current terminal pads

Rev 2 Testing:

STM LED
Analog Reads
CAN
LED Matrix PWM Outputs