Mini PC Power Input Stage: Failed reverse-polarity protection | Auckland
Pattern to record: The adapter is recognised mechanically but no protected voltage appears beyond the input stage.
Identify the input design
Record the mini PC’s input specification before testing. Some models use a fixed-voltage DC adapter and others accept USB-C power; connected USB equipment can add load without changing the computer’s own workload. One possible explanation is that the input MOSFET or protection stage no longer passes valid adapter power.
Stop before further damage
A wrong-voltage adapter can damage the board even if its plug fits. Guessing at MOSFET orientation can expose the board to full adapter current.
Workshop checks
- Compare a known compatible supply, disconnect nonessential devices and trace the protected input path before blaming storage or Windows.
- Compare gate, source and drain conditions using the correct circuit reference.
Repair and power verification
If the checks support this cause, replace the failed protection device after confirming no secondary short remains. Verification should cover cold and warm start, USB load, network activity, sleep and sustained operation.
For an assessment of your mini PC, contact AEPC in Burswood or call 027 908 8880. Provide the model and the conditions that reproduce this problem. Workshop visits are by appointment.