Low Cost NiMH Battery Charger board preprogrammed to charge 3 NiMH cells. Charge profile and number of batteries can be changed with firmware. The design uses the MCP1630 High-Speed Analog PWM combined with the PIC microcontroller. Charge current is initially set for 1.35 A fast charge.
**Features:**
* Programmed parameters - modified in firmware
* Factory Settings:
\- Preconditioning Charge Current =170 mA
\- Preconditioning Threshold = 3 V
\- Constant Current Fast Charge = 1.35 A
\- Charge Termination based on delta - VBATT / delta time
\- Charge Termination based on delta + TBATT / delta time, with external thermistor installed
* Top Off Charge Current = 130 mA for 1 Hour
* Overvoltage protection (battery removed)
* Overcharge protection to prevent damaging the battery
* Overcurrent protection in the event of a shorted battery
* Battery reversal protection
* Input short circuit protection
* Overtemperature protection to prevent the battery from reaching too high a temperature during charge
* Soft-start capability by holding the reference voltage low during power-up
* The MCP1630 Low-Cost NiMH Battery Charger has the flexibility to optimize the charging algorithm for new battery technology, different battery chemistries or different battery pack configurations
* Proprietary features can be added by modifying the firmware contained in the PIC12F683
* The factory-programmed source code is available
* Ability to adapt to environmental effects, such as ambient temperature
