For Rev 1.1

Power Validation

1. Check for continuity between GND, 3.3 V, 5 V, and 12 V. All of these should be isolated from each other.
2. Remove R23.
3. Supply 12 V between GND and 12 V. A current limit of 100 mA should be sufficient for most testing. Switching the relays and/or fans will require more current (up to 4 A). Measure the voltage between GND and 3.3 V, and GND and 12 V.
4. Set PB0 high to enable the 5 V converter. Measure the voltage between GND and 5 V.
5. Connect an oscilloscope probe between GND and 5 V to measure the ripple of the 5 V converter.
6. Turn off the power supply.

HSD Current Sense Output (TPS2H000-Q1)

1. Connect the E-load between the HSD side of the kill switch connector, and GND.
2. Supply 12 V between GND and 12 V.
3. Enable IN2 and DIAG_EN of the HSD (PB8 and PB9).
4. Set the E-load to draw 100 mA.
5. Measure the voltage across D2. If it is 3.3 V, then R23 can be added.
6. Turn off the power supply.

isoSPI (LTC6820)

1. Connect a controller board to the BMS carrier.
2. Connect a logic analyzer to IP, IN, and GND.
3. Supply 12 V between GND and 12 V.
4. Set the CS pin of the LTC6820 being tested low, set MOSI low, set MOSI high, and then set CS high again. The latching edge of the clock will change for different SPI modes. Current sense is SPI mode 1 (clock idles low, latches data on falling edge) and the AFEs are SPI mode 3 (clock idles high, latches data on rising edge).
5. If the LTC6820 is functioning, there will be a long -1 pulse transmitted between IP and IN, followed by a short -1 pulse, short +1 pulse, and then a long +1 pulse. A -1 pulse is when IN switches high before IP. A +1 pulse is when IP switches high before IN.
6. Repeat for each SPI.
7. Turn off the power supply.

Capacitor Inrush Current

1. Connect a shunt resistor between the negative terminal of the power supply and the negative terminal of the BMS carrier board.
2. Connect an oscilloscope probe across the shunt resistor, with the ground terminal of the probe connected to the negative terminal of the power supply. Set the oscilloscope to trigger a single time.
3. Power the BMS carrier board with 12 V between 12 V and the negative terminal of the shunt resistor. Toggle the output of PB9 on and off. Turn off the power supply.
4. Determine the peak voltage, and divide by the resistance of the shunt resistor. The peak current should be less than 1 A.

Enable Relays

1. Connect a controller board to the BMS carrier.
2. Close the kill switch or short the connector.
3. Supply the board with 12 V between GND and 12 V.
4. Set PB9 high to enable the HSD and activate the relay to power the main relay coils. There should be an audible click as the on-board relay closes. Set PB9 low.
5. Set PB4 high to enable the low side switch of the HV GND relay coil. Check for continuity between the GND pin of P10 and GND of the board. The two nets should be connected. Set PB4 low.
6. Set PB3 high to enable the low side switch of the HV PWR relay coil. Check for continuity between the GND pin of P7 and GND of the board. The two nets should be connected. Set PB3 low.
7. Turn off the power supply.

Raspberry Pi