TPS65279: Power good issue

praveenkumar vh

Part Number: TPS65279
Other Parts Discussed in Thread: PCA9535

Hi team,

Im working with TPS65279,

im facing issue regarding power goods, output rails are coming up properly but PG's are always low.

i checked with changing pull up resistor to 10k but no result. i checked with load side where PG's are sampled and both the loads are taking this signal as input.

please note one PG to one load, since this device has 2VR's im sampling one at FPGA and other one at GPIO exp (PCA9535).

TPS65279RHHR - PG issue.pdf

over 3 years ago

0 Lishuang Zhao over 3 years ago

TI__Expert 7500 points

Hi,

You have submit another new thread. I will close this one.

Thanks,

Lishuang

0 Zhao Ma over 3 years ago

TI__Genius 15135 points

Hi, Praveen

I have reviewed the schematic, some comments:

1. Did you ever see the VDD1V2 and P2V5 outputs rise up to their target voltage?

2. There are errors on soft start circuit at SSx pin.

Please remove R15 and R17(130kohm), and change C11=C10=10nF, after that, please test again.

0 praveenkumar vh over 3 years ago in reply to Zhao Ma

Prodigy 130 points

Hi Zhao Ma,

Issue solved ! thank you for your support.

As per your suggestion i removed R15 and R17 and i could able to get power goods.

thank you very much

Praveen

Power management

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TPS65279: Power good issue