MP2639AGR - Push Button Internally Pulled Up to ?V

Hello, Maybe I’m overlooking this but the datasheet says nPB is pulled up internally but then no where that I can find does it indicate what Voltage this pin is pulled up to. I use 3.3V to power all logic systems and that’s sourced from the 5V that’s generated from MP2639A. nPB also connects to my MCU for detection and alternate functionality. So how is nPB internally implemented so I know how to use it in my system?
Thank you

Hello jkellar,

nPB is pulled up using VCC. VCC has an output of ~4.5V. You should only need to attach a push button to nPB. This can be see on figure 1 and 2, which shows the block diagrams for charging and discharging.

Please see the EV2639A-R-00A for an example of its implementation.

Vinh Tran

Hi Vinh,

Very good. So this voltage is even present when 5V input is not applied (e.g. USB) and the MP2639 is in discharge mode correct? What is the approximate current out the PB pin? I’m assuming the PB pin is pulled high via a voltage divider from VBATT input, correct?

You see I’m connecting the PB pin to my MCU also for additional features.