ROCKPro64 pwm-fan inoperable
01-01-2020, 11:46 AM
UPDATE 2:
The root cause has been found. Q2110's collector (pin 3) is floating above the pad on the PCB. Continuity testing confirmed that it is not making the connection. The oscilliscope probing likely applied enough pressure for it to establish connection and I incorrectly assumed that somehow the capacitance was "fixing" what could have been a defective fan.
I am disappointed to not have spotted this before I accidentally poofed R89554. Only later to find out all that would have been needed was to fix the manufacturing/soldering defect on Q2110's pin. That is upsetting. Waited for RP64 because it was on backorder. Now I have to wait for parts to repair it.
The root cause has been found. Q2110's collector (pin 3) is floating above the pad on the PCB. Continuity testing confirmed that it is not making the connection. The oscilliscope probing likely applied enough pressure for it to establish connection and I incorrectly assumed that somehow the capacitance was "fixing" what could have been a defective fan.
I am disappointed to not have spotted this before I accidentally poofed R89554. Only later to find out all that would have been needed was to fix the manufacturing/soldering defect on Q2110's pin. That is upsetting. Waited for RP64 because it was on backorder. Now I have to wait for parts to repair it.