I've built the following circuit based on an ATtiny85 for a night lamp. The circuit is powered by a 3.7v LiPo battery. I'd like to turn off the PIR sensors when the photocell detects light in order to save battery.
I tried putting a 2N2222 transistor between the power and the PIRs VCC pins but that makes the sensors unstable as not enough current was going through. I suspect some resistance by the 2N2222 but I might be wrong. I'm successfully using a 2N2222 to switch the photocell off when I don't need it. The sensors draw 100 uAh when standing by.
Can someone tell me what would be the best and most efficient way to switch (on/off) the current of the PIR sensors?