TPS784-Q1: VFB/output voltage setting and Cff recommendation

user4979989

Part Number: TPS784-Q1

Hi team,

Please help to check my questions as below.

The TPS784-Q1 (adjustable version) VFB is 1.2V, right? since I am not able to find the parameter in EC table, I can only find the minimum output voltage of adjustable version is 1.2V.

I am not able to find recommended Cff in the table, is it ok to place 0.01uF non-pop?

Thank you.

Regards,

Allen

over 4 years ago

0 JCHK over 4 years ago

TI__Mastermind 44590 points

Hi Allen,

For the adjustable version, if the desired output voltage is 1.2V, simple short VFB to VOUT. It is not practical to use a CFF capacitor when the device is operating in unity gain

I hope this helps to clarify.

0 user4979989 over 4 years ago in reply to JCHK

TI__Intellectual 2800 points

Hi John,

If the Vout is set to 1.25V, we can use R2 = 51k ohm and R1 = 2.125k ohm, is it correct?

If 1.25V output, what value should be set for Cff (we can non-pop it first, just a placeholder)

Regards,

Allen

0 JCHK over 4 years ago in reply to user4979989

TI__Mastermind 44590 points

Hi Allen,

In Adjustable mode, VFB is 1.25V. So simply tie FB to VOUT for 1.25V operation.

Regards,

Power management

Power management forum

TPS784-Q1: VFB/output voltage setting and Cff recommendation