END OF PRODUCTION WARNING

This will be the last batch of production due to chip shortage and increasing production cost. This product will retire after all the stocks sold out. Thank you all for your support on this product and please look forward to a future revisions!

What is it?

This is a battery powered USB hub for the Pi zero W, designed to run with ArozOS as a pocket cloud server. It also works with any Pi NAS systems (e.g. OMV) and be able to work as a generic battery powered USB hub for most ARM single board computers that run Linux.

Quick Showcase Video

https://www.youtube.com/watch?v=eyJz5iCwuvg (The video showcase the older version with a micro USB charging port, the current version features a type C charging port instead)

Notes before buying

1. Raspberry Pi zero W, Micro SD card and LiPo battery not included
2. If you buy more than 1 units, they will be sent attached (See the picture above with 2 PCB connected together)
3. Require a bit of soldering skills to make it work

Specification

• HT4928S Lithium polymer battery management IC (Input: 5V 0.8A, Output: 5V 0.8A, up to 91% conversion efficiency)
• SL2.1A USB 2.0 Hub
• 3 X USB 2.0 Type A port for connecting USB storage devices, WiFi adapter and power (from battery)
• 1 x USB type C port for charging (5V 0.8A)
• White indicator LED, blink while charging and low battery, turn on when discharging with internal regulator.
• Size: 113.5mm x 36.6mm x 8.5mm (thickest point)
• PCB: 1.5mm Green silk with lead
• Connection: This adapter board contains 4 pins for connecting to the USB D+, D-, 5V and GND test pad on the bottom of the Pi zero W

Features for hackers

• The 4th USB port is implemented as test pads (between the USB port and the power switch) for future upgrade / extension
• Provide test pins (2.54) for both USB host and battery, allowing the use of other similar form factor ARM SBCs (e.g. Banana Pi M2Zero)

Battery Choice

Recommend LiPo battery that is rated for 3.7 - 4.2v (1C).

You can also use 18650 with protection circuit built in or old smartphone LiPo battery with protection circuit built in. In the sample build above (and in the video), it uses 2 x 1100mAh LiPo with internal protection & balancing circuit. It rans for around 10 hours with WiFi on and no external USB device plugged in.

Why did you make it?

I made this for my personal project called "Pocket Cloud Server" with ArozOS. This also serve a great platform for using Pi Zero W in off-grid deployment like during conference / Maker Faire demo.

What makes it special?

• Ultra thin form factor (< 1cm even with the Pi zero W soldered on)
• Work with any LiPo / 18650 at 3.7v - 4.2v range
• Type C port for charging
• SL2.1A as USB Hub controller instead of the cheaper FE1.1S, less heat = longer run time
• Physical power switch