The MCP1630 Li-lon reference design is a versatile charger design capable of charging up to two single-cell, Li-lon battery packs in a parallel configuration. The reference design features LED drivers to achieve the voltage-based fuel gauge indication and distinguish charge mode from discharge mode. The design can work with a wide input voltage range from 10V to 28V and has multiple safety features. The power train used for this reference design is a single-ended primary-inductor converter (SEPIC). This reference design is suitable for use as a stand-alone charger for the Li-Ion battery pack.
As shown in the figure above, the reference design can be daisy-chained to charge up to 32 cells by combining 16 reference design modules in parallel. The reference design employs a PIC microcontroller and programming header pins that allows the user to add proprietary features by coding the microcontroller. Moreover, the reference design offers the flexibility to optimize the charging algorithm for newer battery technologies. The reference design also employs a dual operational Op-Amp and is capable of automatically detecting the status of the battery pack.
The working of the charger can be explained through the firmware flow chart of the reference design shown below.
Firmware Flow Chart
Features of MCP1630
- Programmable parameters – modified in firmware
- Flexibility to optimize the charging algorithm for new battery technology and add proprietary features by coding the microcontroller.
- Controlled soft-start.
- Over Voltage Protection (battery removed).
- Over Charge Protection to prevent the battery from becoming dangerously overcharged.
- Over Current Protection in the event of a shorted battery.
- Battery Reversal Protection.
- Input Short Circuit Protection.
- Over Temperature Protection to prevent the battery from reaching too high a temperature during charge.
- Fast charge termination if the battery temperature is outside a preset window.
All the design resources such as the documentation, BOM, PCB layout and Gerber files are provided by the company, but in order to access the files you first need to register with your e-mail address.
You can find the design resources here.