Sensor power control

ecolyx

Hi,
I've been playing with various sensors and controllers on the GPIO, using wiringPi library, uploading metrics to a graphite/carbon apache server.

Some of the sensors draw significant power (enough to affect battery life adversly for the project requirements).

Some of the sensors/controllers also affect each others readings if powered at the same time. For instance a solenoid affects a compass. Reading EC of a liquid requires generating a signal which will affect the voltage across a pH sensor.  And so on..

I want to be able to switch off the sensors between reads and save power.

It's relatively easy to power 3v3 sensors with a HIGH GPIO pin, but I am struggling with 5v sensors.

Is there any way to control the 5v supply, or is there a switchable 5v supply on the boards (particularly OPi One, or OPi 0+2, as they are models I am using), without additional circuitry?


Could I use a GPIO pin to ground the sensor on LOW, switching it off with HIGH?

Thanks for any ideas..

nopnop2002

You can control 5v power using MOSFET.

http://www.electronics-tutorials.ws/transistor/tran_7.html