Part Number: TPS56837
Tool/software:
I need a review of the schematic for my circuit. We have been using the TPS56837, and the converter keeps shorting at startup of the system. from a load perspective, we have 2 fans ( 3 amps max each) and 2 LNA ( .2 amps max each). i have 2 ICS for redundancy
We did same additional testing last week to see what kind of inrush current apears. Its showing a 1 milisecond 20 amp surge. would this have a large impact on the ICS?
We do have soft start but use a 22nf capacitor for the SS pin.
1) Also we do use both at the same time - is this a problem to do that? -
2) We can only see the short when plugged into the system that is powered by batteries. we hear a popping noise and smell burning. we do notice the battery's do have a drop in voltage very briefly on startup. We were unable to get the short to happen when the system is plugged into the the bench setup with a power supply.
3) Because we cant get this issue to be repeatable, we cannot get the waveform data on the voltage when this failure mode occurs.
- would it be better if i used a much larger capacitor for the SS pin to lower the inrush? or should i design a 20 amp power supply using a buck controller to mitigate this issue?
