TPS54327: and TPS54527 Start up delay time

Hi

This delay time should besically depend on EN and Vin rising time,

Vout begins to ramp up must satisfy two conditions, EN goes higher than threshold and VIN goes higher than VREG5 UVLO,

if Vin goes higher voltage>UVLO before EN ramp, once EN ramp to threhold, Vout begins to soft-start.

You can also refer to 7.4.1 and 7.3.3 in 54327 DS for details.

BR,

Yuchang

Thank you for reply.

I'm sorry.I understand my question is hard to understood.

I understand the following.

"This delay time should besically depend on EN and Vin rising time"

What I would like to know is that when EN = High after VIN goes up,
It is the delay time until Vout starts Soft Start.

I am sorry that there is no regulation, please cooperate.

Regard

Hi Kishi,

There should be no delay between EN high and soft start for TPS54327. After EN is high, SS cap start to charge up. It means that the internal reference will start to rise and Vout will follow the reference to increase also. 

Best,

Anthony