Safe Shutdown v1.2 for Adafruit Powerboost.
- Works with software to issue a shutdown command to the Pi.
- Keeps system powered until Pi shuts down.
- Works with Adafruit PowerBoost 500c/1000c.
- Works with the PowerBoost LBO pin to alert you of a low battery.
- DPDT switch included.
- Octagonal PowerBoost Headers (BAT/EN/GND/LBO).
- Circular Raspberry Pi Headers (3.3v/Shut-off/Keep-on/Low Battery).
New in v1.2
Some people reported issues with the previous version shutting off immediately if the charging cable was connected. This has been resolved.
A slightly thicker PCB and ground planes on both sides mean this version is easier to solder and more resistant to heat. That said, these boards are still very small and heat up quickly, so please take care and use a low temperature when soldering.
The PowerBoost and Raspberry Pi headers are in the same order as the devices they connect to. This means you can use a ribbon cable without swapping any wires.
v1.2 is 4mm shorter. Every little helps!
- Safe Shutdown PCB v1.2.
- DPDT Switch.
- Octagonal BAT connects to the Bat or Vs pin of the PowerBoost.
- Octagonal EN connects to the EN pin of the PowerBoost.
- Octagonal GND connects to the GND pin of the PowerBoost.
- Octagonal LBO connects to the LBO pin of the PowerBoost.
- Circular 3.3v is the 3.3v pin (physical pin 1 or 17)
- Circular On is the keep-alive pin, usually BCM/GPIO22 (physical pin 15)
- Circular Off is the shutdown pin, usually BCM/GPIO27 (physical pin 13)
- Circular Low is the low battery pin, usually BCM/GPIO17 (physical pin 11)
Please take care when handling and soldering these boards. They include static-sensitive components and have a low thermal mass. Damaged boards with burnt traces or pads cannot be replaced.
Additional things to note:
- This version will not work with an original DMG-01 power switch.
- You may need a tiny blob of hot glue to prevent the PCB from rotating around the screw hole.
Please remember to install the Power Monitor script, otherwise the Pi will not shut down.
This version uses the LBO pin on the PowerBoost in order to ensure the power is cut after a low battery shutdown. Unfortunately, with the boards I've received I have seen kernel panics at this point. I'm not sure if this is another issue with the sourced components for assembly, but the GBZ does shut off shortly afterwards.
As long as you are using a battery with a built-in protection board, there should be no real issue. The GBZ will eventually power off after a few minutes. I suspect the duration will vary from device to device (depending on the current draw of your components, and your battery capacity), but I'll be making adjustments to the script so it makes use of the remaining charge before shutting down.
This will only ever happen if the GBZ is left unattended and powered on. In a low battery situation, one would ideally connect a charging cable or switch the GBZ off until it can be charged. I wanted to be up front and mention it anyway.