TPS22963C: Application Circuit Question

Jerry Chu

Part Number: TPS22963C

Hi Expert,

If the VBUS_CHGR_USB didn't have power in, but VOUT has the power. Does it any risk that VIN get the power Vout? Because C2 pin didn't connect to GND. Thanks!

over 7 years ago

0 Nicholas Carley over 7 years ago

TI__Expert 8715 points

Hi Jerry,
I don’t see a risk in your current implementation assuming VBUS_CHGR_USB is at 0V, the device will be disabled.
When the device is disabled, it will not allow current to flow towards the input side of the switch.
Let me know if you have any other questions.
Best,
Nick

0 Nicholas Carley over 7 years ago in reply to Nicholas Carley

TI__Expert 8715 points

Hey Jerry,

I wanted to clarify my earlier statement. Section 11.1.4 of the datasheet discuss reverse current blocking.

It looks like Vin will equal 0V, therefore for reverse current blocking to turn on, Vout needs to be higher than 1V.

Best,

Nick

0 Jerry Chu over 7 years ago in reply to Nicholas Carley

Genius 4915 points

Hi Nick,

If there are no VBUS power, the C2 pin will be float. But Vout>Vin, TPS22963C still can protect the revers current?

0 Nicholas Carley over 7 years ago in reply to Jerry Chu

TI__Expert 8715 points

Hello Jerry,

With the on-pin floating (and Vin floating) there is no guarantee that the part will turn on reverse current blocking, even if Vout>Vin.

It would be best to attach a pull-down resistor (large resistor from enable to ground) which will guarantee that the on-pin is at 0V and not floating.

If you have any other questions please let me know.

Best,

Nick

0 Jerry Chu over 7 years ago in reply to Nicholas Carley

Genius 4915 points

Hi Nick,
Thanks, I will do it.

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TPS22963C: Application Circuit Question