Power Supply Ignition and other Switches for the Raspberry Pi

There are several occasions where you may require operating your RBPi or Raspberry Pi powered from a vehicle’s electrical system. To keep your single board computer safe and operational, an accessory is needed to sense when the ignition on the vehicle is engaged and when it is turned off. Accordingly, the accessory will respond by powering the RBPi on or off safely. MausBerry Circuits make such safe power supply ignition switches and other shutdown switches for the RBPi to be used in vehicles.

The power supply ignition switch attachment from MausBerry features a built-in step-down converter that produces 5V from the 12 or 14V of the vehicle’s power supply. Once connected with wires behind the vehicle’s radio, the attachment provides the RBPi with instructions based on the vehicle’s ignition status. It communicates with the RBPi using two of its GPIO pins.

An added advantage of the ignition switch attachment is it can retain power for about 20 minutes during its power-down cycle. That means the RBPi will remain powered for 20 minutes after the vehicle’s ignition is switched off, so waiting for the RBPi to boot is not required for those making frequent stops. A selector switch on the device will allow you to reboot the RBPi, if required. Even if the RBPi was left in the vehicle and not shut down, there is no cause to worry. The automatic shutdown feature of the device will kick-in to shut the RBPi down after four hours of non-use, thereby preventing drain on the batteries.

MausBerry makes many other similarly useful attachments for an RBPi to be used with vehicles. One of them is the 3A car supply that can sense the car ignition to shut down the RBPi safely when the car is turned off. The unit has two USB ports and communicates with the RBPi using two GPIO wires. The unit is to be wired to the vehicle’s battery and the 12V ignition source. Ground and power wires, both 18AWG and 18-inches long, are included.

If you are looking for an on-off switch for your RBPi, MausBerry has an illuminated LED type switch. Plug this unit into the RBPi power port and it accepts your existing micro-USB power cable. To turn the RBPi on, simply press the button. To switch off, press the button again briefly – the operating system senses the button and safely shuts itself down. After a safe shutdown, the switch will cut off all power to the RBPi. When illuminated, the LED gives off a bright blue light, and holding the button for five seconds performs a hard-reset for the RBPi.

Although aligned to the layout of the RBPi models A and B primarily, the illuminated LED shutdown switch will work directly with all models A, A+. B, B+, RBPi2 of the RBPi series. For the B+ models, the new power port location may make the switch stick a little out of the side.

Another shutdown circuit from MausBerry allows you to use any custom switch for operating the RBPi. The circuit plugs into RBPi power port and accepts the micro-USB power cable. This circuit is useful when installing the RBPi into a case, as the switch can be installed separately.