Switching the input to LMR10520

Valentin Popa

Other Parts Discussed in Thread: TPS2115, LMR10520

We switch the input to the LMR10520 using a TPS2115 from V_BUS to 5V_FROM_12V as seen in the schematic bellow.

Everything works fine as long as we have V_BUS connected and at 5V but the issue is when we disconnect V_BUS.

The 5V_OUT after V_BUS is down is shown in first picture and the LMR10520 output is presented in second picture.

Why this behavior?

Thanks,

Valentin

0 Frank De Stasi over 9 years ago

This looks like a problem with the TPS2115. It seems to be letting voltage from the other input through to the output.

I would move this post to the group responsible for that switch.

0 Valentin Popa over 9 years ago in reply to Frank De Stasi

I posted the issue initially in that forum but I didn't get an answer in the past 10 days.

The issue seems to be indeed that on TPS2115 some of the voltage on the OUT pin is coupled into the IN1 pin but not sure how to eliminate that.

0 Valentin Popa over 9 years ago in reply to Valentin Popa

Anybody else here has an idea what could be the issue?

Power management forum