Hi,
So I'm trying to get my phone portable charger to power the arduino, but once I press the momentary switch on the power supply it will turn the arduino uno on only for 11 seconds. I would like to replace the momentary switch with something that keeps it on constantly or off constantly, - switch basically. After hot wiring the connectors of the momentary switch, using a wire to create an on and off state, it still is only working for 11 seconds. I need to know how to get this working constantly.
Crack it open and take a peek. My guess is that it has some current sensing and minimum current threshold, which below that, it shuts off and the Arduino just doesn't draw enough to keep it "awake". You could use the arduino to regularly pulse the "on" line like wake up call.
I use 2 100 Ohm 1/2 Watt resistors in parallel across Vcc and GND, wastes 1/2 Watt (100mA) but keeps the power bank on.
A better way would be to use a transistor switch to cut the resistor in about 100 milliseconds every 5 seconds or so with an output pin.
I built such a device using a 555 timer and a PNP transistor to shunt a 47 Ohm resistor across the output to simulate a load. The duty cycle for my power bank is about 1 percent (20mS on , 2 Seconds off).
I got the idea from forum article (somewhere). My solution is a bit more elaborate than necessary but is good for initially experimenting with the power bank to get the right balance between reliability and wasted power.