TPSM84424: TPSM84424 sequencing

Hi,

    PGOOD is an open drain output and you need a pull-up resistor when using stand-alone or trying to sequence other devices. The Fig 22 in the datasheet can be considered as a logical figure for such cases. But when you have two of the TPS84424 connected as shown in Figure 22, the it might be ok because the EN pin of the TPS84424 can be floated or pulled high. So, the PGOOD will pull the EN pin low and once PGOOD is asserted-high, the EN pin's current source will pull the pin high to enable the second converter.

Hope this clarifies.

Regards,

Gerold

okay, that's what I thought.

btw, what is the recommended pull-up resistor value and voltage?  The datasheet stated 10K-100K ohms... 

Thanks,

Tim

Hi Gerold,

as I recall previous comment suggested it does need pull-up "PGOOD is an open drain output and you need a pull-up resistor. The Fig 22 in the datasheet can be considered as a logical figure. I will ask the team to add  the pull up resistor for clarity."

Anyhow, I just wanted to clarify one more time whether the pull-up is needed?  In the case it does not require pull-up, what would happen when there is a pull-up? is there a problem?   

Thanks,

Tim

Hi Tim,

   I dont see any issue in having a pull-up resistor on that pin. 

Regards,

Gerold

Hi Gerold,

That for the info, it's good to know.   Again, just wanted to confirm - it does not require any pull-up as you explained in previous feedback, am I right?

Thanks,

Tim