Sleepy Pi 2 – Micro USB B

Raspberry Pi add-on board for Smart Power Management and additional GPIO.

• Run Raspberry Pi on Battery Power
• Extend RPi battery life from hours -> weeks / months
• Deep Sleep, with Wake on Event or Time
• On-board Arduino for user programs
• Adds Arduino Analogue & PWM IO
• Battery-backed Real-Time clock / calendar
• Avoid SD Card corruption with proper shutdown
• Works with all 40-pin Raspberry Pi Models (Zero/W, A+, B+/Rpi2, Rpi3B/3B+ and Rpi 4 – see caveat below)

(For Raspberry Pi 4 compatibility see this post )

Imagine, you’ve just created your first Raspberry Pi project and you’re really proud of yourself. You pat yourself on the back, box it up, plug in the batteries and send your baby out into the Big Wide World. Success! Hurrah!

However…..6 hours later your marvellous creation has stopped working, worse still the SD card with all your code on, that took days to debug, has corrupted.

No problem, you’ll buy new batteries and restore the SD from backup……. You DO have a backup, right??

Battery Hungry

The Raspberry Pi is a fantastically powerful, small and cute computer. Ideal for portable, battery powered applications. But it’s not designed for battery power! For example, the Raspberry Pi Model 3B does not have a direct battery input and consumes around 500mA of current during normal operation. Put another way, if you provide it with a regulator to use batteries, typical AA battery packs will only give you a couple of hours use (see the Raspberry Pi Battery Life Calculator).

The Raspberry Pi has NO LOW POWER MODE!

Many applications do not need the Pi to be powered at all times and could benefit from emulating the typical low power strategies common in modern microcontroller systems.

How It Works

Do you know how most modern devices save power? They switch to a low power “sleep” mode whenever they’re not being used and wake only when they next need to do something. The Sleepy Pi replicates this type of behaviour on the RPi. It allows the RPi to shut itself down when it’s not being used to save power and wakes it up when it’s got work to do (get back to work!) either at timed intervals or when some real-world signal cries out for attention.

For example, you’ve got a long term Timelapse project in mind. You want to snap a picture every 10 minutes and store it. It takes about 10 secs to snap and store. What does the RPi do with the other 9mins and 50 seconds??? Run your batteries down or waste some more mains electricity?