TPS563202: Maximum Allowed Output Capacitance of TPS563202?

Senthil Seveelavanan18

Part Number: TPS563202

Hello

I want to use as much capacitance as possible with the TPS563202.
What is the maximum capacitance allowed?

Thanks

over 2 years ago

0 Zixu Wang over 2 years ago

TI__Expert 8100 points

Hi Senthil,

My colleague will give you reply by next week!

BRs

Zixu

0 Ruby Li over 2 years ago

TI__Expert 7430 points

Hi Senthil

When the output cap is over 220uF, there may be multipulse.

Hope this helps.

Ruby

0 Senthil Seveelavanan18 over 2 years ago in reply to Ruby Li

Prodigy 140 points

Hello Ruby,

Is this just for the initial capacitor inrush, or an ongoing behaviour?

Please could you explain this multipulse more, can you link to an explanation?
Is this related to thermal or current limiting?

If this multipulse behaviour is due to the initial inrush current, could this be solved with a soft start circuit?

Thanks

0 Zixu Wang over 2 years ago in reply to Senthil Seveelavanan18

TI__Expert 8100 points

Hi Senthil,

My colleague will give you reply later!

BRs

Zixu

0 Ruby Li over 2 years ago in reply to Senthil Seveelavanan18

TI__Expert 7430 points

Hi Senthil

When considering maximum output caps, there are a few things needed to be taken into consideration:

1. Soft start: since we have fixed soft start time, if the output cap is too large, the output voltage could not be built after the soft start time and there will be large inrush current. A soft start circuit could help here.

2. The output cap and inductor would affect the loop performance. If your output cap is rather large, the inductor should be small to make sure that the double pole caused by LC would not be much smaller than the injection zero. Multipule would happen here if it is unstable. See the app note in the below link:

https://www.ti.com/lit/an/slvaf11/slvaf11.pdf?ts=1669862863473

Add Cff would help here.

Hope this helps.

Ruby

Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

Power management

Power management forum

TPS563202: Maximum Allowed Output Capacitance of TPS563202?