Zero2Go Omini Rev2: Wide Input Range Power Supply

This is the Rev2 version of the popular Zero2Go Omini. The Rev2 version uses a USB-C connector for the channel A input and introduces a new VIN-GND-VOUT header on the left edge of the board, which allows you to add additional channels and manage power for devices besides the Raspberry Pi.

Zero2Go is a Raspberry Pi Zero sized (or ‘pHAT’ shape) extension board that can work as a wide input range power supply for Raspberry Pi. The board offers a wide input range (3.5V-28V), so it is convenient to power your Raspberry Pi with a power bank, Li-Po battery, solar panel, car battery or other power adapters and sources. You can also configure it as a UPS (please read the user manual for more details)

Zero2Go Omini Rev2 supports all Raspberry Pi models that have the 40-pin GPIO header, including A+, B+, 2B, 3B, 3B+, 3A+, Zero, Zero W and 4B (however you will need a USB-C power supply for this version).

Note: The Zero2Go Omini doesn’t charge the connected battery. Rev1 version with micro-USB connection available here. Raspberry Pi is not included.

Features

• Three separated input channels (each accepts 3.5~28V DC)
• Auto step-up or step-down to output 5V for powering Raspberry Pi
  • Up to 2A for Step-Up mode, up to 3.5A for Step-Down mode
• Auto switch input channel (one with the highest voltage takes the priority)
• Gracefully turn on/off Raspberry Pi with a single tap on the button
• Fully cuts power for Raspberry Pi and all its USB peripherals after shutdown
• Long hold the button to force power cut, when OS loses response
• Monitor the input voltage on each channel (via software)
• Shutdown Raspberry Pi when input voltage below a preset threshold
• Recover Raspberry Pi when input voltage exceeds a preset threshold

How does it work?

Please see the simplified diagram below. It demonstrates the main functionalities of Zero2Go Omini and can help you to understand how it works.

When V_in is lower than 5.5V, the step-up engine will be used; When V_in is 5.5V or higher, the step-down engine will be used instead. The Zero2Go can switch between step-up and step-down modes automatically.

User Manual

• PDF User manual

Software Installation

To install Zero2Go’s software, please run this command in your home directory:

wget https://www.uugear.com/repo/Zero2GoOmini/installZero2Go.sh

If your Raspberry Pi has an internet connection, it will immediately download the script from our website, and you will then see the “installZero2Go.sh” script in your home directory. Then you just need to run this script with sudo:

sudo sh installZero2Go.sh

You will need to use sudo to run this script. This script will copy a file to “/etc/init.d/zero2go_daemon”, and register it to run after the boot.

Conflicts with 1-Wire Interface

If you have 1-Wire interface enabled and didn’t specify the GPIO pin for 1-Wire, it will use GPIO-4 and that conflict with Zero2Go Omini. Zero2Go Omini uses GPIO-4 to receive shutdown command, if GPIO-4 is also assigned to 1-Wire, Zero2Go’s software will receive shutdown command unexpectedly. If your Raspberry Pi always automatically shutdown itself after installing Zero2Go’s software, that is most probably due to the conflict with 1-Wire interface.

When this happens, you most probably can not log in to your Raspberry Pi because it always shuts itself down before you get the chance to log in. To solve this problem, you will need to take out the micro-SD card on your Raspberry Pi and access its file system via a card reader. You need to edit the config.txt file in the “boot” volume to change the GPIO pin used by 1-Wire interface, or you can disable 1-Wire interface if you don’t need it for now. You need to find something like “dtoverlay=w1-gpio” in the file.

If you want 1-Wire to use GPIO-18, just change “dtoverlay=w1-gpio” to:

dtoverlay=w1-gpio,gpiopin=18

If you want to disable 1-Wire interface, just comment it out:

#dtoverlay=w1-gpio

Save the file and eject your micro SD card, and put it back to your Raspberry Pi. Now your Raspberry Pi should be able to boot normally.

Package Contents

• 1x Zero2Go board Rev2
• 4x 4mm plastic spacer
• 4x M2.5 x 10mm plastic screws
• 4x M2.5 plastic nuts

Raspberry Pi and 40-pin header are not included in the package.

Specifications

Dimension:	65mm x 30mm x 7.7mm
Weight	13g (net weight)
Mainly Used Chips	MCU: ATtiny841 (datasheet) DC-DC Bulk: MP4462 (datasheet) DC-DC Boost: SDB628 (datasheet)
LED Indicator	Three-color LED (red, green and blue)
Interface	USB Type-C female connector for input channel A. XH2.54-2P connector for input channel B. Universal wire connector for input channel C. 20×2 header (h=2mm) for connecting Raspberry Pi.
Input	Three separated channels (A, B, and C) All accept DC 3.5V~28V (5.5~7.0V is not recommended as the DC-DC bulk converter needs more dropout to work well)
Output	Output 5V (±5%), maximum 2A
Efficiency	Up to 87% @ Step-Up mode Up to 82% @ Step-Down mode
Standby Current	~0.13mA @ Vin=3.5V ~0.36mA @ Vin=12V ~0.87mA @ Vin=28V
Operating Temperature	-30℃~80℃ (-22°F~176°F)
Storage Temperature	-40℃~85℃ (-40°F~185°F)
Humidity	0~80%RH, no condensing