LTC4447

The LTC®4447 is a high frequency gate driver with integrated bootstrap Schottky diode that is designed to drive two
N-Channel MOSFETs in a synchronous DC/DC converter. The powerful rail-to-rail driver capability reduces switching losses in MOSFETs with high gate capacitance.

The LTC4447 features a separate supply for the input logic to match the signal swing of the controller IC. If the input
signal is not being driven, the LTC4447 activates a shutdown mode that turns off both external MOSFETs. The input
logic signal is internally level-shifted to the bootstrapped supply, which functions at up to 42V above ground. The Schottky diode required for the bootstrapped supply is integrated to simplify layout and reduce parts count.

The LTC4447 contains undervoltage lockout circuits on both the driver and logic supplies that turn off the external MOSFETs when an undervoltage condition is present. An adaptive shoot-through protection feature is also built-in to prevent the power loss resulting from MOSFET crossconduction current.

The LTC4447 is available in the 3mm × 3mm DFN package.