Buck-Boost Battery Charge Controller with MPPT and I2C
The LT8491 from Analog Devices is a buck-boost switching regulator battery charge controller that implements a constant-current constant-voltage (CCCV) charging profile used for most battery types, including sealed lead-acid (SLA), flooded, gel and lithium-ion.
Applications are expected to include solar powered battery chargers (see simplified schematic above), multiple types of lead-acid battery charging, Li-ion battery chargers, battery-equipped industrial or portable military equipment, and similar devices.
The LT8491 operates from input voltages above, below or equal to the output voltage and can be powered by a solar panel or a dc power supply. On-chip logic provides automatic maximum power point tracking (MPPT) for solar powered applications.
The LT8491 can perform automatic temperature compensation by sensing an external thermistor thermally coupled to the battery. The STATUS pin can be used to drive an LED indicator lamp. The device is available in a low profile (0.75mm) 7mm × 11mm 64-lead QFN package.
Summary of features:
- VIN Range: 6V to 80V
- VBAT Range: 1.3V to 80V
- Single Inductor Allows VIN Above, Below, or Equal to VBAT
- Automatic MPPT for Solar Powered Charging
- Automatic Temperature Compensation
- I2C Telemetry and Configuration
- Internal EEPROM for Configuration Storage
- Operation from Solar Panel or DC Supply
- Four Integrated Feedback Loops
- Synchronizable Fixed Frequency: 100kHz to 400kHz
- 64-Lead (7mm × 11mm × 0.75mm) QFN Package