Is is possible to use capacitive touch as a power switch for an embedded project?
Can a microcontroller turn itself off and somehow still monitor an input pin? Or is there a dedicated IC that can cut and enable power to the rest of the circuit while using very little power itself?
Best Answer
You could use a pSOC device of which there are quite a few variants. These are a Programmable System On a Chip made by cypress semiconductors and they comprise of a microcontroller with a set of configurable analog and digital subsystems. Tseveralmof the devices have inbuilt capacitive touch inputs and they can operate at very low power.
Alternatively if you already have a chosen microcontroller, then a CMOS gate could be used as a capacitive touch input d this could be used to bring your controller out of standby/sleep or even switch a transistor to allow full powerup.