TPS54880: TPS54880

huu dang

Prodigy 30 points

Part Number: TPS54880
Other Parts Discussed in Thread: TPS54810, , TPS54680

I am usingTPS54880 and if Trackin pin is not used Do I need to hook up to anything or live floating?

over 8 years ago

0 JohnTucker over 8 years ago

TI__Guru**** 191445 points

If you are not going to use that function, then I recommend you consider the very similar TPS54810. For the TPS54880, you will have an extremely fast internal slow start time.

0 huu dang over 8 years ago in reply to JohnTucker

Prodigy 30 points

This is an old design and I am trying to fix the issue. We are using TPS54880 regulator to generate 1.25V and TPS54680 to generate +2.5V from a +5V external supply . Both PSU supplies are tracking an external +3.3V. and depend on the ramping up timing between +5V and +3.3V . +2.5V and +1.25V sometime going into a UVLO condition and it doesn't have a smooth ramp up condition. I could send you the plots and schematic for you to review and comment.
Regards,
Huu

0 JohnTucker over 8 years ago in reply to huu dang

TI__Guru**** 191445 points

I can take a look at it. Generally this type of issue is somewhat difficult to troubleshoot over the forum.

0 JohnTucker over 8 years ago in reply to JohnTucker

TI__Guru**** 191445 points

Also,

Why do you think floating TPS54880 TRACKIN pin will fix your issue?

0 huu dang over 8 years ago in reply to JohnTucker

Prodigy 30 points

Something that I need to explore, since tracking seem to start before Vin reach minimum voltage. I guess I have to talk to FAE in my city then.

0 JohnTucker over 8 years ago in reply to huu dang

TI__Guru**** 191445 points

There is a disclaimer in the TPS65880 datasheet that states you should use the ENA input to enable the supply after the input voltages are above the UVLO.
"To provide power up tracking, the enable of the I/O supply should be used. If the I/O enable is not used to power up, then devices with similar undervoltage lockout thresholds need to be implemented to ensure power up tracking. To ensure power down tracking, the enable pin should be used."

Is that something that applies to you?

Power management

Power management forum

TPS54880: TPS54880