How to Repair China 20A Battery Charger | High Voltage Blast Repair (Mosfet, IC & Capacitors)

Welcome to another practical electronics repair tutorial! In this video, I will show you how to diagnose and repair a dead 20-Ampere China battery charger that suffered severe damage due to high input voltage (overvoltage surge). Due to the voltage spike, the main filter capacitors, PWM driving IC, and primary switching MOSFETs were completely burned out. I will take you step-by-step through:- Tracing and testing the input stage and primary section- Identifying blown electrolytic capacitors and selecting the right voltage/capacitance rating- Checking and replacing the shorted switching MOSFETs- Testing the PWM controller IC and surrounding SMD gate resistors / diodes- Final safety precautions, power-up test using a series bulb, and verifying output charging voltage and currentWhether you are working on solar battery chargers, SMPS power supplies, or basic electronics repair, this guide will help you troubleshoot similar overvoltage faults safely and effectively.