3 This is a simple but effective, dual-rate, standalone charger for Lithium
4 Polymer batteries. It supports who different charge rates, approximately
5 100mA and 500mA. The higher rate is good for batteries of 400 mAh and higher
6 including the 900mAh cells sold with [TeleMetrum](../TeleMetrum) starter kits,
7 while the lower rate is more appropriate for the 110mAh cells often used with
8 [TeleMini](../TeleMini). A standalone charger is essential for use with
9 TeleMini since it does not have on-board charging capability.
15 * Micro USB connector for power input
16 * 2mm JST-style connector for battery
19 * green when charge complete
20 * both on, or "yellow", when battery is disconnected or bad
21 * 1.0 x 0.4 inch board
23 ### Developer View ###
26 * [Microchip MCP73831](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en024903) Li-ion battery charger chip
28 * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
30 * The hardware is licensed under the [TAPR](http://www.tapr.org) [Open Hardware License](http://www.tapr.org/ohl.html)
34 The design files can be found on [git.gag.com](http://git.gag.com) in the
35 project [hw/lipocharger](http://git.gag.com/?p=hw/lipocharger;a=summary).
39 After some iteration, we have settled on a design that meets our needs.
40 Boards will be available for sale soon.