MSXV DCDC Validation

05-2023

• During the test, the capacitor discharge circuit started smoking

• Once working, DCDC output max is 10.6-10.7V

17-06-2023

• R7: 549.5; R8: 4.715k; R9: 1k

  • So looks like R8 is off as it should be 10k

• TR to HV GR it's only 3.511kohms (should be a little over 15kR)

6-2023

• Replaced R8 to 10k ohms resistor, but seems like the resistor removed was 10k

• Connected back to the power supply and load no change in output voltage

27-06-2023

• mosfet gate and drain/source is not shorted

• r8 is replaced with 10kohm resistor

30-06-2023

• Testing the DCDC output with the replaced resistor (R8)

Test 1: Replaced resistor

• CC (Load): 0.100A

• Voltage (PSU): 60-100V

• Power consumption: ~1.060W

• Results:

  • no resistance across TR and HV GND

  • outputting ~10.6-10.8 volts from the range

Test 2: Removed R10

• no resistance from TR to HV GND

• Voltage output is slightly higher, around 10.7V at 60V input

Test 3: Replaced Q2

• Same conditions: input voltage 60V

• Same output voltage: ~10.7V

• Suspected leg 2 of Q2 is not properly connected

  • when checking conductivity leg 1 & 3 were good

26-07-2023

• removed R7, resistance from TR to EN is ~19.9kohms

• power supplied from 90-120V, outputs constant 12V