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LM5155: parameter design to improve loop stablity

Part Number: LM5155

Dear expert,

My customer is using LM5155, but find loop is unstable.

        1. Vin=9~36V,output 5V/6A(30W);

        2.Due to the PCB size limit, the output capacitor is 100uF*3 MLCC, Lp=9~11uH;

        3.When debugging,if current sense resistor R12=0.003R then loop is always unstable. If R12=0.015R then the loop performance is better, however still can't carry full load at 9Vin;

        4.When slow down the loop (C25=C26=0.33uF,R20=200R,C23=0.033uF,C24=0.01uF,R21=1K), then the load capacity is better, but still not complete stable and dynamic performance is bad.

 

Please see their schematic as below. Could you help to share a better parameter design? Thanks for your support.