Hii,
I am designing 60W DC-DC buck converter with help of MP9928.
Input voltage: 13V - 54V
Output voltage: 12V
Output current: 5A
Rfreq: 37.4K => ~520kHz
Rfb1: 169k
Rfb2: 12k
When I run the converter at full load 5A for long run, output voltage steadily reduced to 10V after run about 10 minutes.
Question:
1). What critical parameter I am missing in understanding?
2). Which components should I change?
3). How to calculate the compensation network resistor and capacitor value?
Thank you.
Greetings,
Divyeshkumar
Hi @D.Sanchaniya,
Is Vin constant for whole operation? Please monitor if Vin is within the range.
Please refer to the compensation components section in the Application Information to determine the compensation component values. You can also visit here and scroll down to design resources where you’ll find the simulation file which will help you finalize the components as well.
Additionally, kindly follow the PCB guidelines in the DS for optimal performance.
Thank you
Saurabh
HII @MPSNow_Saurabh
Sorry for late response. My Vin is almost nearly constant for all time (within range).
In my circuit R3 & C7 was the problem, I removed R3 and make that connection open and then working fine.
As shown in attached picture, I am getting small overlap between two switches like shoot through fault so mosfets getting very hot around 90 °C, to remove this overlap, I tried by putting 10R gate resistor in upper switch but that didn’t worked.
I want to take MP9928 component in LTspice simulation so how I can take this part in LTspice?
I already tried to find out on Google but not worked.
