TPS25730: Hook up question for VIN_3V3 pin

Phillip Mobley

Part Number: TPS25730

Tool/software:

Hello everyone,

I am desiging a USB PD circuit that uses the TPS25730SRSMR chip. I have everything configured using the example schematic provided in the datasheet. My output will be the 20 V @ 5A.

I have a quick question regarding the VIN_3V3 pin. It is not clear to me how to connect this pin. Should I:

1) Use a 3.3V regulator and connect this to the pin
2) Can I use the LDO_3V3 pin on the chip and connect it to the VIN_3V3 pin?

Please let me know

Best

over 1 year ago

0 Phillip Mobley over 1 year ago

Prodigy 60 points

So reading this question here, https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1368123/tps25730-leave-vin_3v3-floating,

I would like to confirm again that I since I am always going to be powering the chip from VBUS (USB C PD. My device will always be acting as a sink) I don't need to connect VIN_3V3 and can leave it floating. Is this correct?

0 Christopher Lim1 over 1 year ago in reply to Phillip Mobley

TI__Mastermind 37855 points

Hi Phillip,

Phillip Mobley said:
I would like to confirm again that I since I am always going to be powering the chip from VBUS (USB C PD. My device will always be acting as a sink) I don't need to connect VIN_3V3 and can leave it floating. Is this correct?

Yes, that is correct.

Phillip Mobley said:
Can I use the LDO_3V3 pin on the chip and connect it to the VIN_3V3 pin?

Do not do this, VIN_3V3 should be left floating and should never be connected to LDO_3V3

Thanks and Regards,

Chris

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TPS25730: Hook up question for VIN_3V3 pin