SIM800C power on/off transistor

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1

I want to be able to toggle on/off the SIM800C module by pulling-down its PWRKEY pin, but that pin is internally pulled-up to vBatt (3.4V~4.4V) which is too much for a 3.3V MCU.

The datasheet for the SIM800C has an example on how to use a transistor for powering on/off the module but it does not show any part number for the transistor and I'm not sure if the 2N3904 that I have will work correctly or how to calculate the values for the resistors.

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It will work correctly (presumably 10k/100k would also suffice).
Pay attention to the pinout and do not mix Base/Collector/Emitter pins.

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