TPS7A52-Q1: Capacitance at BIAS Pin

Charan MMJ

Part Number: TPS7A52-Q1

Hi,

I am using TPS7A5201-Q1 LDOs in my design.

One LDO is used to generate 0.9V (@0.4A) from 1.2V
Another LDO is used to generate 1.2V (@1A) from 1.5V.

I am connecting 5V supply to the BIAS pin of both the regulators. As per datasheet, minimum capacitance at the BIAS pin should be 10uF.

Is it OK to combine both the capacitors and connect only one 22uF for both the bias pins of 2 LDOs (Doing this because there is space constraint and I have multiple such LDOs on board)?

Or Is it strictly recommended to connect separate 10uF at BIAS pin for each IC?

Thanks in Advance.

8 months ago

+1 Stephen Ziel 8 months ago

TI__Mastermind 35965 points

Hi Charan,

The requirement is more of an impedance spec rather than capacitance per LDO BIAS pin. A single capacitor with 10uF capacitance will meet the impedance target for both LDO's simultaneously, so you only need a single capacitor. You do not need a capacitor for each LDO.

Thanks,

Stephen

0 Charan MMJ 8 months ago in reply to Stephen Ziel

Prodigy 90 points

Hi Stephen,

Thank you for the reply. Is there any routing and capacitor placement guidelines for that capacitor?

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TPS7A52-Q1: Capacitance at BIAS Pin