LM5022-Q1: Error Compensation

Dear Sir,
The expert of this part will help to check your schematic once back to the office. Please wait in patient.

Hello Gerardo,

Can you please remove the inductor (Ls), resistor (Rs) and the diode (Ds) that are in series with the MOSFET? What are the purpose of these components? I think thins might be causing the errors during simulation.

Thanks,

Garrett

Hi Garrett,

Ls,Rs,Ds help me to avoid high reverse peak current on the  main diode, avoiding the failure of it. However,following your idea, the output voltage changes its behaviout a little but on the other hand I have a destructive reverse recovery current as you can see in the following graphs.

You may choose a different diode. However, why do you say the reverse recovery is damaging? You should add a RCD snubber from the MOSFET drain to GND, so the reverse recovery current would be absorbed by the snubber capacitor.

Thanks,
Youhao Xi, Applications Engineering

Hello Youhao Xi.

I changed the diode and the situation seems even worse. However, the RCD snubber helps the MOSFET during the turn-off, I got this issue during its turn-on. So, I used a LRD snubber in order to reduce the current slope and get a lower reverse recovery current. The value is damaging for the diode because the max reverse peak current is 2 A.

Thanks,

Gerardo

I was mistaken. I added a RCD snubber but the situation is even worse.

Is your circuit the TINA model? If yes, you may send your model to us for an investigation.

Thanks,
Youhao