Hello E2E community,
I have done two power supply designs using TPS546A24A with pin strapping only. The PCB have been built and assembled and I'm experiencing some trouble on start-up due to instability.
-Input 10V, freq 550kHz, output 1.8V up to 6A
-Input 10V, freq 550kHz, output 1.1V up to 8A
As you can see on the picture below the chip is trying to start-up but is oscillating which is causing the chip to stop.
/cfs-file/__key/communityserver-discussions-components-files/196/0016.TIF
I have tried to play with different compensation setting using the excel spread sheet but with no success. I have read on another thread that it might comes from a too big inductor which can make difficult to the current loop to adjust my calculated value was around 1.7uH but I have used a bigger one to reduce a bit more the ripple.
Below are the two designs let me know your thoughts, is there something wrong ?
/cfs-file/__key/communityserver-discussions-components-files/196/0058370A_2D00_SCM.pdf
/cfs-file/__key/communityserver-discussions-components-files/196/0058371A_2D00_SCM.pdf
Cheers
Yann