Buck-boost controller for wide-input, single-inductor regulation
It operates from a 2.7 V to 10 V supply and switches at a user-programmable frequency between 100 kHz and 1 MHz, allowing the designer to optimise the power-stage for efficiency or inductor size. The controller drives external N-channel MOSFETs in a single-inductor topology, with synchronous rectification built in to maintain efficiency at low output voltages. Control features include current limiting, enable, and soft start.
Switching frequency and inductor sizing
The switching frequency is set by an external resistor to ground and can be synchronised to an external clock within the 100 kHz to 1 MHz range.
Synchronous rectification and efficiency
Synchronous rectification eliminates the forward drop of a Schottky diode by replacing it with a second N-channel MOSFET driven by the controller.
It is ROHS3 compliant, meaning it contains no restricted substances above the exemption thresholds, including lead, mercury, cadmium, and the four phthalates.