Part Number: TPS43060
Hi,
We are using the TPS43060 in an amplifier module to provide a 35V 4A supply. The input voltage range is from about 19Vmin to 29V max. The supply works well until the board starts to heat up under load. A full power after about a minute or so the TPS43060 starts to pulse its output on / off at a regular interval (between the Vin and 35V at few Hz) and afterwards the TPS43060 runs very hot (~80C) with no load on the supply but still seems to work. To fix the problem you need to replace the IC.
The board layout is as per the guidelines and a via is used to connect the pad under the IC to the 0V plane for cooling.
The power supply circuit and PCB layout is below. Note the PCB is 4 layer with the pad connected to the 0V plane.
What is the likely cause of the damage to the IC?
Regards,
Hugh
