Charge controller LT8491 with MPPT and I2C support,
Provides three selectable CC-CV charging profiles
Built-in all charge termination algorithms, reducing design time


Analog Devices (ADI) announced on the 15th the launch of the 'LT8491' buck-boost battery charge controller supporting maximum power point tracking (MPPT), temperature compensation, and I ² C interface functions for telemetry and control applications.

The LT8491 operates regardless of whether the input voltage is above, below, or equal to the regulated battery float voltage. It offers three selectable constant-current, constant-voltage (CC-CV) charge profiles, making it suitable for charging a variety of cell chemistries, including sealed lead-acid batteries, gel cells, flooded cells, and lithium-ion.

All charge termination algorithms are built-in, so users do not need to develop separate software or firmware, reducing design time.

The LT8491 operates over a 6V to 80V input voltage range and can output a battery float voltage from 1.3V to 80V using a single inductor with 4-switch synchronous rectification. Charging currents up to 10A are possible depending on the selection of external components, and multiple 'LT8705' 80V buck-boost controllers can be connected in parallel to support even higher power topologies.

Even if partial shadowing of the solar panel causes a local maximum power point, the true maximum power point can be found by sweeping the entire operating range of the solar panel.

Once the actual maximum power point is found, the system operates at that point using dithering techniques to track slow changes from the maximum point. This allows the system to utilize nearly all of the power generated by the solar panel, even under less-than-ideal operating conditions.

Automatic temperature compensation can also be performed by sensing an external thermistor thermally connected to the battery. The ^I2C interface controls the input/output voltage, current, and power values, as well as the charger.

The LT8491 is available in a low profile 0.75mm 64-pin 7mm x 11mm QFN package and operates over a -40˚C to 125˚C temperature range.