Hello,
We are using TPS566238RQFR device in our design. Input supply provided to this device is 5V and output would be 0.9V @4A. The schematic is attached for your kind reference.
Observations: There are high ripples in the output power supply at 0.9V. Snapshot of the waveform is attached for your reference.
(Note : Oscilloscope bandwidth set to 20MHz.)
Kindly review the schematic and let us know how to make these ripples at the output of the device (TPS566238R) to minimum.
Regards,
Santosh
Hello Santosh,
I reviewed the schematic.
The output side of your schematic does not seem to have any issues. The recommended LC components are in place here.
As for the input side, what is the purpose of R677? And what is NU?
In addition, please make sure you are measuring using tip and barrel method on the output cap as this is a key factor in minimizing ripple, and ensure AC coupling. If you could please share waveforms of SW and VIN this would help to see what could be the issue.
Below is a reference output voltage ripple waveform from the datasheet. This is a good comparison.
Thank you,
Calan
