Q: TPS71501 with output connected buck output? by 578832

I will use TPS71501 to generate 3.2V from 12 to 23V in..  Will also connect a 3v3 buck output voltage in parallel to the output of the TPS71501.. The TPS71501 would work as standby power and when the buck is enabled (starts up) the output output be forced to 3v3..

Question  - will the TPS71501 be damaged if the output is forced 0.1V above the regulated output voltage while the input voltage would be 12-23V?  Would the " Leakage Null Control Circuit" activate and pull down the TPS71501 output ?


A: Re: TPS71501 with output connected buck output? by 1108707

The Leakage Null Control circuit is a very weak pull-down which keeps the output from floating up above Vout during light or no load conditions. If the target is 3.2 and the Vout is acutally 3.3V, the circuit will be active but as it is a weak pull-down this should not present a problem in the application.

The effective pull-down resistance is on the order of 5M Ohm. So this really should not impact anything in the application.