Ultralow Power Boost Converter with Dual Half-Bridge Switches

The LT8415's integrated N-channel and P-channel MOSFETs in each half-bridge are synchronously controlled by a single input pin, and never turn on at the same time maximizing system reliability for applications such as MEMs relays. The internal MOSFETs are sized to drive capacitive loads ranging from a few pF to several nF without issue. The LT8415 integrates the main switch, half-bridge switches, Schottky diodes and output disconnect on a single die, packaged in a 2mm x 3mm DFN. The LT8415's wide 2.5V to 16V input voltage range enables it to operate from single-cell Li-Ion batteries up to fixed 12V input rails, delivering outputs up to 40V. The output voltage can be adjusted dynamically by driving the FBP pin with an external voltage source.

The LT8415 can deliver over 700uA of average output current at 34V from a single Li-Ion cell making it ideal for applications such as MEMs relays or biasing power. Both parts use a unique control technique that delivers efficiencies as high as 88% and low output ripple (<10mVPK-PK) over a wide load current range. Other features include integrated soft-start and overvoltage protection. The combination of the LT8415's 2mm x 3mm DFN package and tiny, low cost ceramic capacitors and inductors provides a very compact solution footprint.