Tool/software:
Hi,
We designed Dual Synchronous Buck Controller using LM5143QRWGRQ1 for input voltage of 50V and output load of 5V, 30A.
When we powered ON the module at no load, with input set voltage of 50V and set input current limit of 50mA in external power supply. It results failure of IC (VCC pin short was observed) and module output voltage not observed.
However at same condition, we increased the input set current limit in external power supply of 1.5A, it works and output voltage was observed at 5V.
We connect VCCX pin of IC to output voltage 5V, to reduce the power dissipation of LM5143.
Is there any possible of failure of IC, with lower set input current limit in external power supply? Or any other reason for this failure?