TPS54541: Negative voltage output Monitoring Problem

Ganesh C

Part Number: TPS54541

Hi,

We have used the TPS54541 IC for +12V & -12V generation. It is working.

But when we probe the -12V regulator for current measurement, the IC output was shorted with Ground. (Just Ammeter connected as per diagram, and powered ON. No output from the IC.)

Input voltage is 24VDC.

The Image as shown below.

Please let us know, why this problem was occurred? How we can resolve this problem?

Thanks,

Ganesh C

over 2 years ago

0 Andy Chen over 2 years ago

TI__Mastermind 27045 points

Hi Ganesh,

The circuit design has big issue on grounding:

C61 and C63 ground should be shorted directly.

You need to add 0.22uF 50V ceramic cap close to VIN pin and D15 GND

First you can try to use the battery powered DMM to measure the output current to avoid instrument case GND issue

B R

Andy

+1 Ganesh C over 2 years ago in reply to Andy Chen

Prodigy 10 points

Hi Andy Chen,

Thanks. I will consider your recommendations.

Regards,

Ganesh C

0 Andy Chen over 2 years ago in reply to Ganesh C

TI__Mastermind 27045 points

Pls upload PCB layout if problem still existing....

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TPS54541: Negative voltage output Monitoring Problem