I am working on a project ( Instructable soon to be published) which required the Arduino controller to be powered down once a program had been run and restarted at the push of a button. The Pololu Pushbutton Power Switch fit my needs perfectly. This device was so easy to use and has so much potential in other projects I thought I would do a quick write-up in the hopes of helping others.
I use the Arduino as an example, but many other configurations are possible.
Step 1: The pinouts
I am using the low voltage version which can handle 2.5-7 volts. The standard version can handle 4.5-20 volts. A small switch is provided, but any momentary on switch can be used.
The pinouts of the switch are pretty straight forward. There are two pins for Voltage In (VIN), two for Voltage Out (VOUT), four for ground (GND) and one pin marked OFF.