TPS22954: TPS22954 output capacitance

Vidhya Jeyapaul

Intellectual 780 points

Part Number: TPS22954

HI Team,

Vin,Vout =3.3V

Load current=1A

PFA schematics.

How much is the output capacitance to be used?

Kindly revert.

Thanks,

Vidhya

over 3 years ago

0 Kalin Burnside over 3 years ago

TI__Genius 13300 points

Hello Vidhya,

We generally recommend 1uF of input capacitance and 0.1uF of output capacitance for our load switches, but the output capacitance generally depends on your application. What ever capacitance you end up using you should make sure the inrush current drawn from it doesn't exceed ABS values and adjust your CT value to account for it.

Inrush Current Control

Regards,

Kalin Burnside

0 Vidhya Jeyapaul over 3 years ago in reply to Kalin Burnside

Intellectual 780 points

Hello Kalin,

CT value chosen to be 1nF.

There is no graph shown for Vbias=Vin=3.3V

As we have CT setting, 0.1uF output capacitance should be fine?

What is the rise time and slew rate for Vbias=Vin=3.3V?

Kindly revert.

Thanks and Regards,

Vidhya

+1 Kalin Burnside over 3 years ago in reply to Vidhya Jeyapaul

TI__Genius 13300 points

Hello Vidhya,

Yes, it should be for our device. The following table should apply for 3.3V = Vin = Vbias

Regards,

Kalin Burnside

0 Vidhya Jeyapaul over 3 years ago in reply to Kalin Burnside

Intellectual 780 points

Hi Kalin,

Vsense resistors are fine? Can you please confirm?

VSNS > 0.565V to drive PGOOD.

we have used 56K and 12K on 3.3V with VSNS=0.582V

Kindly confirm.

Thanks,

Vidhya

+1 Kalin Burnside over 3 years ago in reply to Vidhya Jeyapaul

TI__Genius 13300 points

Hello Vidhya,

Yes, with R2 = 12kΩ and R1=56kΩ it means you'll achieve a valid signal by 3.2V, and invalid by 2.3V at the lowest and 2.8V at the highest. The 10.3K they currently have on the schematic doesn't ensure a valid voltage across the range.

Regards,

Kalin Burnside

0 Vidhya Jeyapaul over 3 years ago in reply to Kalin Burnside

Intellectual 780 points

Thanks Kalin.

56K and 12K resistors are used.

Regards,

Vidhya

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TPS22954: TPS22954 output capacitance