EG7500 Inverter Drive Board Testing and Query? Answered
Specification EG7500 Inverter Drive Board.
PWM freq 40kHz.
Overvoltage shutdown 15V +-0.5V.
Low voltage buzzer beep 10.5 +-0.5.
Undervoltage shutdown 9.5 +-0.5.
Overcurrent shutdown 48mV.
1A Output current drive.
Carry out a test by varying DC between 9V to 15V. Resulted:
1. At 10V to 10.5V buzzer beep. "OK"
2. At 9V to 9.5V or below 9V the unit shutdown. "OK"
3. At 13V to 13.5V ran into off and trying to restart the unit (Board marked A). "NG"
4. At 14.5V to 15V ran into off and trying to restart the unit (Board marked B). "OK"
Refer to above test how to improve "Board Marked A" overvoltage shutdown?
Which part of the schematic to begin troubleshoot. What component I needs to change or improve?
Once power up. This unit draw ~0.5A on standby.
How do I minimize the standby current?
There are no temperature control since P3 "S8550" was not on board.
Can I just put "S8550" on board and use PTC for temperature control?
As proposed by schematic online, pin 4 fan control feet to ad 100uF to ground.
How do I change this part to enable fan control once the temperature rise?
How many FET this unit can drive with 1A at 40kHz?
How to test the overcurrent shutdown?