TPS54429 with TPS74401

Sneha Kumari

Other Parts Discussed in Thread: TPS54425, TINA-TI, TPS74401, TPS54429

Hi,

I am trying to simulate the power supply using Tina-Ti. Again, the combination is TPS54425 with TPS74401 causing some problem for me.(Previous post : https://e2e.ti.com/support/development_tools/webench_design_center/f/234/t/418044). TPS54429 output is connected to VIN and BIAS of TPS74401. Also, PGOOD of TPS54425 is applied as TPS74401 ENABLE. When simulating, PGOOD is not going HIGH, it is always low. When this connection is removed from TPS74401, PGOOD is working fine.
I am using the new model of TPS74401 shared in the previously mentioned post ("7612.TPS74401_TRANS.lib")

Thank you very much.

regards,

Sneha

over 11 years ago

0 Britt Brooks - Online Design Tools over 11 years ago

TI__Mastermind 41310 points

Sneha,

Could you post your .TSC file? We would need to take a look at the circuit to see what is occurring.

I do not recall an issue with the LDO model enable causing the PG signal to be effected.

0 Sneha Kumari over 11 years ago in reply to Britt Brooks - Online Design Tools

Intellectual 320 points

Dear Britt,

Thank you for the reply. The problem was with the run time, TPS54429 PGOOD will be active after 1.7times soft start time. I was not running the simulation until that. In my case, PGOOD will be active ~1mS, after rampup.

Sorry for the inconvenience.

regards,
Sneha

Simulation, hardware & system design tools

Simulation, hardware & system design tools forum

TPS54429 with TPS74401