MP2456 Heating Problem

[vinod]

HI,
We have made a custom board with MP2456 with similar schematics as the evaluation board with 33uH inductor and DLFS160 etc. We have device heating up badly and goes to thermal shut down.
If we power the device with 24V (output is 12V) it works well but still heats to around 45 degrees (external infrared reading).
If we raise the input to 40V or 42V the device goes to thermal shut down!!
Is this device recommended for 12V 500mA application with 32 to 42V input (10S cells)
kind regards
Vinod Ganesh

[MPSnow_Nouman]

Hi Vinod,
Device should be ok to operate within this range, please confirm proper layout recommendations are followed as well as needed reverse current protection.

Best,
Nouman

[vinod]

This is the current layout. The chip starts to cut off the output at 38 to 42V. Chip is happy at 24V input and no drama at 24V whatsoever.

[vinod]

The above is the circuit diagram

[vinod]

here is the bottom layer also for reference

[vinod]

For the benefit of everybody, the layout on this design worked beautifully. So i assume the previous design had wrong ground paths.