Witty Pi 3 Mini - RTC + Power Management for Raspberry Pi Zero

Witty Pi is small electronic circuit board that can add a real-time clock and power management to your Raspberry Pi. The Witty Pi 3 Mini is a new member of the third generation of Witty Pi, and it has pHAT shape (Raspberry Pi Zero size).

Features

The Witty Pi 3 mini is packed with power management features such as:

• You can gracefully turn on/off Raspberry Pi with single tap on the switch.
• After shutdown, Raspberry Pi and all its USB peripherals’ power are fully cut.
• Raspberry Pi knows the correct time, even without accessing the Internet.
• Raspberry Pi knows the temperature thanks to the sensor in RTC chip.
• You can schedule the startup/shutdown of your Raspberry Pi.
• You can even write a script to define complex ON/OFF sequence.
• Monitor external voltage and turn on/off your Raspberry Pi accordingly.

Raspberry Pi Support

The Witty Pi 3 Mini supports all Raspberry Pi models with a 40-pin GPIO header, including A+, B+, 2B, Zero, Zero W, 3B, 3B+, 3A+ and 4B.

Software

The Witty Pi 3 Mini uses the same software as the Witty Pi 3. You just need to run these two commands in your Raspberry Pi to install the software:

wget http://www.uugear.com/repo/WittyPi3/install.sh

sudo sh install.sh

Differences with the Witty Pi 3

Comparing to the Witty Pi 3, the Witty Pi 3 Mini uses the same RTC chip (DS3231SN) and same micro-controller (ATtiny841). The main difference is the LDO voltage regulator (LM29150) which is not populated on the Witty Pi 3 Mini. This reduces the cost for those who don’t need an LDO, and also makes things easier to integrate a different DC/DC module into the Witty Pi 3 Mini.

The Witty Pi 3 Mini uses a super capacitor (0.08F, or 80000uF) instead of the coin-cell battery used in the Witty Pi 3 for time keeping via the built-in RTC.

You can find more information in its user manual: http://www.uugear.com/doc/WittyPi3Mini_UserManual.pdf

Each Witty Pi 3 Mini package contains:

• Witty Pi 3 Mini board x 1
• M2.5 x 10mm plastic screw x 4
• 4mm spacer x 4
• M2.5 plastic nut x 4