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ADM1278 Start Up Current Limit  & Software Reset Behavior

Question asked by henry-tang on May 15, 2017
Latest reply on May 17, 2017 by henry-tang

Hi ADI Expert,


What will happen if inrush current reach ADM1278 start-up current limit?

Will ADM1278 begin to regulate inrush current and Vtimer will also start to be pulled up VtimerH ?

If the load capacitors can be charged before Vtimer reach VitmerH, then system can be successfully powered on.

On the contrary, if TIMER pin is insufficient to allow the load capacitors to charge, which means Vtimer reach VTimerH then the MOSFET will be disabled and system will not power up?





If my assumption is correct, can you please kindly help to answer below questions : 

1. What's the timer pin pull up and pull low current during this Start-up power sequencer?

2. Will fault pin also be asserted for this start-up OCP event? 


Lastly, I have another question is about POWER CYCLE command

This command let user can ask hot swap to turn off and turn back on again.

So can  ADM1278 register be cleared and reset by this command? 

And will ADM1278 start power on initial sequence again until PWRGD is asserted? 



Any comment or suggestion is highly appreciated!