TPS2121: Power Sequence

Katsuya Sato

Part Number: TPS2121

Hi Experts,

Is it acceptable to use the TPS2121 under the following conditions?

When there is no power supplied to IN1 or IN2, an independent 3.3V is provided to PR1. During power-down, the 3.3V to PR1 is dropped after IN1 and IN2 have been turned off. The Recommended Operating Conditions in the datasheet state that PR1 can range from 0V to 5.5V, and there are no specific instructions regarding the sequence.

However, if there are any recommendations such as it being better to supply PR1 through a voltage divider from IN1, please let me know.

Best Regards.

5 months ago

0 Patrick Shalton 5 months ago

TI__Mastermind 20290 points

Hi Sato-san,

PR1 can be powered regardless of IN1/IN2 state. Typically it's recommended to use a resistor divider on PR1 but if your application works better by controlling it externally then that's fine.

Thanks,

Patrick

0 Katsuya Sato 5 months ago in reply to Patrick Shalton

Prodigy 85 points

Hello Patrick,

Thank you for your response.

I am considering to provide an independent 3.3V to OV2 pin to no use IN2 as output.

Is it possible to directly apply 3.3V to the OV2 pin?

Thanks, Katsuya

+1 Patrick Shalton 5 months ago in reply to Katsuya Sato

TI__Mastermind 20290 points

Hi Sato-san,

Yes, directly applying 3.3V to either OV pin is ok as well.

Thanks,

Patrick

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TPS2121: Power Sequence