LM5121: Help to review the schematic

Hi Hsu,

Thanks for reaching out with your comments. Please see my advice below.

1. Inductor Saturation: Make sure the inductor has rated saturation current greater than 7.5A. 7.5A is the cycle by cycle peak inductor limit.

2. Compensation: I suggest changing the following components to improve the phase and gain margin of the control loop. R6 = 22kOhm, C12 = 22nF, C11 = 680pF.

3. Current sense resistor filter: I suggest adding a filter the current sense signal. This filter helps to filter out and high frequency that might get coupled into the filter.

Please let me know if you have any questions.

Thanks,

Garrett