Reset Signal working

[Rahul Soni]

I have two buck converters. If one is driving the reset# signal low and another is driving the reset# signal high, what output will be going to the other IC's. I have give the same name to both of the reset# and I am sending them to two different IC's

 

[KlausST]

Hi,

connecting two push pull outputs together isn´t a good idea. Use an OR gate instead.

****
Often #resret outputs are open collector/open drain. You may connect them and use a pullup resistor.


Klaus

 

[Rahul Soni]

Hi,

****
Often #resret outputs are open collector/open drain. You may connect them and use a pullup resistor.


Klaus

I have done the same thing. Those reset signals are coming from the PGOOD pin which is driven by an internal MOSFET (open drain). When any MOSFET goes low, the other will automatically go low since both the outputs are connected to the same net (Reset#) and the resulting output will be low. Thus the Reset# will make the other ICs low

 

[KlausST]

Hi,

so you answered your own question....

*****

and another is driving the reset# signal high,

With open drain output one does not speak of "driving high", instead it is high_Z = floating,
but the pullup resistor does it´s job...


Klaus

 

[Rahul Soni]

Hi,

so you answered your own question....

Yes

Klaus

*****

With open drain output one does not speak of "driving high", instead it is high_Z = floating,
but the pullup resistor does it´s job...


Klaus

Thanks for this information.