How to order Contact us Distributors Reviews
Register / Login

Select currency

If you'd like to view estimated pricing in other currencies then please select a currency below below.

GBP USD EUR JPY AUD NOK CHF NZD CAD

Please note:

  • Currency conversions are estimates and for information only
  • Your order will be billed in GBP
  • All prices exclude VAT / other local sales taxes
  • Shipping calculated during checkout


Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy

by Adafruit
An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy An image of Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy

If you have an ItsyBitsy or Pro Trinket you probably know it's the perfect little size for a portable project. This LiPoly backpack makes it really easy to do!

Instead of wiring 2 or 3 boards together to make a charging system, this little PCB sits on top of the PCB and allows a LiPoly/LiIon battery to plug in. When the Pro Trinket or ItsyBitsy USB port is powered, the battery is recharged automatically. Unplug the USB port and the microcontroller will switch over to the rechargeable battery.

Ideally, this backpack is for use with the 3.3V Pro Trinkets & ItsyBitsy, so that the battery voltage (3.7V-4.2V) will get regulated down to 3.3V on the board. However, many times, you can run a 5V microcontroller + accessories off of the ~4V from the LiPoly battery with no problem. (Technically its overclocking but we've never seen that affect the microcontroller itself, AVRs are happy to overclock without complaint).

Solder the backpack on with the extra long header so that it can still plug into a breadboard, or clip the long header leads short afterwards for a slim package. There are two LEDs - one red and one green. While charging, the red LED is lit. When the battery is fully charged and ready for use, the green LED turns on. Seriously, it could not get more easy.

If you want to add an On/Off switch, Adafruit also made that really easy. The two 0.1" holes with a box around them are the battery output line. Carefully cut the trace between them with a hobby knife and replace with two wires from a switch like this slide switch, for example.

Charging is performed in three stages: first a preconditioning charge, then a constant-current fast charge and finally a constant-voltage trickle charge to keep the battery topped-up. The charge current is 100mA by default, so it will work with any size battery and USB port. If you want you can easily change it over to 500mA mode by soldering closed the jumper on the bottom, for when you'll only be charging batteries with 500mAh size or larger.

For use with Adafruit LiPoly/LiIon batteries only! Other batteries may have different voltage, chemistry, polarity or pinout.

  • Comes assembled and tested
  • Uses the 5V input via Micro-B USB connector on the Pro Trinket or ItsyBitsy
  • For charging single Lithium Ion/Lithium Polymer 3.7/4.2v batteries (not for older 3.6/4.1v cells)
  • 100mA charge current, adjustable to 500mA by soldering a jumper closed

Batteries and Pro Trinket or ItsyBitsy not included.

Note: You may get an off-white or a black JST connector. It's normal for the the red and green LED's to be very faintly glowing when the battery is attached but not charging, there is 500uA reverse-leakage current from the schottkey diode from the battery that backpowers the charger chip.

TECHNICAL DETAILS

  • Dimensions: 15mm x 17mm x 2mm / 0.6" x 0.7" x 0.08"
  • Height w/ JST: 7mm / 0.3"
  • Weight: 1.3g
  • Datasheets, PCB files and Fritzing available in tutorial page

Reviews

User photos

If you have an ItsyBitsy or Pro Trinket you probably know it's the perfect little size for a portable project. This LiPoly backpack makes it really easy to do!

ADA2124

You must register for an account and be logged in to view pricing or place an order on the Pimoroni Wholesale store.

If you represent a school or university, a business, or reseller of Maker products then you can sign up for a wholesale account.

If you already have an account you can login to your account here.

Alternatively the easiest way to get your hands on the products we offer is to order them directly from our customer facing online store.

SKU
ADA2124
EAN
0700161461695
Brand
Adafruit
Stock available
0 units
Backorder not allowed on this product
Weight
5g

Video introduction

Guides & tutorials

Search

 

Region

Your search returned no results.

Subscribe

We'll keep you up to date with new product launches!

The good ship

We've been sailing the Maker seas offering our wares since 2012.

  • read about our history
  • what our customers say
  • find a local distributor
  • contact our business team

We manufacture all of our products locally at our workshop in Sheffield, UK

Under one roof

Pimoroni are your one-stop shop for bulk and education purchasing of Raspberry Pi, Pimoroni, micro:bit, Adafruit, Sparkfun, and many other brands.

If you have any questions about what we offer then drop us a line.

Pimoroni Ltd

Unit 1, Parkway Business Park,
Parkway Drive,
Sheffield,
S9 4WN,
United Kingdom

Registered in England and Wales:
Company №: 07510759
VAT Reg №: GB 140 8707 21