The Maximum Power Point Tracking (MPPT) enables the LT8491 to perform a sweep of the full operating range of a solar panel to find the true maximum power point, even in the presence of local maxima points caused by partial shading of the panel. Once the true maximum power point is found, the controller will operate at that point while using a dithering technique to track slow changes in the maximum point. Using these methods, the LT8491 can fully utilise nearly all the power generated by a solar panel even in non-ideal operating environments.

The LT8491 operates over a 6V to 80V input range and can produce a 1.3V to 80V battery float voltage output using a single inductor with four-switch synchronous rectification. The device is capable of charging currents up to 10A depending on the choice of external components. The LT8491 may be paralleled with multiple LT8705 80V buck-boost controllers, for higher power operation.

The LT8491 can perform automatic temperature compensation by sensing an external thermistor thermally coupled to the battery. The I²C interface allows control of the charger as well as I/O voltage, current, and power values.

In addition to the MPPT feature, the controller has temperature compensation and I²C interface for telemetry and control. The device operates from input voltages above, below or equal to the regulated battery float voltage.

The LT8491 offers three selectable constant current constant voltage (CC-CV) charging profiles, which make it suitable for charging a variety of battery chemistry types including sealed lead acid, gel and flooded cells and Li-Ion. All charge termination algorithms are provided onboard, eliminating the need for software or firmware which reduces design time.

The LT8491 is available in a low profile (0.75mm) 64-pin 7.0 x 11mm QFN package. It is guaranteed for operation from -40°C to 125°C.