Ideally, this backpack is for use with the 3.3V Pro Trinket, so that the battery voltage (3.7V-4.2V) will get regulated down to 3.3V on the Pro Trinket board. However, many times, you can run a 5V Pro Trinket + accessories off of the ~4V from the LiPoly battery with no problem. (Technically its overclocking but we've never seen that affect the Pro Trinket itself, AVRs are happy to overclock without complaint).
If you want to add an On/Off switch, we 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, or this pushbutton one, 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.
- Comes assembled and tested
- Uses the 5V input via Micro-B USB connector on the Pro Trinket
- 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
Note: Batteries and Pro Trinket not included.
- Dimensions: 15mm x 17mm x 2mm / 0.6" x 0.7" x 0.08"
- Height w/ JST: 7mm / 0.3"
- Weight: 1.3g
- MCP73831 Datasheet
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This depends on where you are located. After the order is handed over to UPS, the delivery time in Germany is about 2-3 days, within Europe about 1 week.
We ship our orders with UPS (United Parcel Service).