I repaired a 5v 20A smps. its working now, but when i connect a load to it, its output drops to 3.7v from 5v. What will be the reason. Plz help .

 

What is the load?

Maybe it's not really fixed?

 

I repaired a 5v 20A smps. its working now, but when i connect a load to it, its output drops to 3.7v from 5v. What will be the reason. Plz help .

Does the feedback circuit sense that the voltage has dropped and does it change its output accordingly?

You connected a load - how many amps did this load draw?
Is there a "Current Sensing" Resistor?

 

I repaired a 5v 20A smps. its working now, but when i connect a load to it, its output drops to 3.7v from 5v. What will be the reason.

Probably still broken.

 

Does the feedback circuit sense that the voltage has dropped and does it change its output accordingly?

You connected a load - how many amps did this load draw?
Is there a "Current Sensing" Resistor?

I connected led display of current around 6A.i replaced all shorted resistors, power transistors, ic etc.
How do i check weather the feedback is coming or not.