Power Sequencing Different Turn ON and Turn off conditions

Hari T O0

Hi Team,

I have three voltage regulator IC's(LDO/Switcher) let it be X1,X2,X3. My turn on condition is such that first X1 should turn on

next X2 and X3 after that. I know how to implement this circuit.

The question is my turn off condition is such that first X2 should go off then X3 and finally X1.May I know

how to implement such conditions.This is a question come to my mind when I was studying power sequencing,don't know whether this

is a non sense question or not.If this question make sense please answer it.

Regards

Hari

over 6 years ago

0 Ryan Eslinger over 6 years ago

TI__Guru 55940 points

Hi Hari,

In order to achieve sequencing you will need to make sure that your selected regulators have the ability to be enabled/disabled by an external signal. Many LDOs have an enable pin which provides this function. We do have sequencing ICs that may be useful for your application. You can learn more about power sequencers at the following link:

www.ti.com/.../overview.html

Very Respectfully,
Ryan

0 Hari T O0 over 6 years ago in reply to Ryan Eslinger

Genius 3820 points

Hi Ryan,
Thank you very much.

May I know how to approch when turn on sequencing is different from Turn off sequencing.If you don't mind could you please explain]
with an example.

Thanks & Regards
Hari T O

0 Qian Chen over 6 years ago in reply to Hari T O0

TI__Mastermind 24075 points

HI Hari,

We will have someone from our sequence team to take a look.

Thanks
Qian

0 yihe over 6 years ago in reply to Hari T O0

TI__Guru 66060 points

We do have a fully programmable solution to support what you need.
it can not only sequence the rails, but also monitor the voltage/current, do fault logging and house keeping.
www.ti.com/.../ucd9090a
Regards
Yihe

Power management

Power management forum

Power Sequencing Different Turn ON and Turn off conditions