Synchronous Rectified Buck MOSFET Driver

The RAA220001 is a high frequency MOSFET driver designed to drive upper and lower power N-channel MOSFETs in a synchronous rectified buck converter topology. In the RAA220001, the upper and lower gates are both driven to an externally applied voltage that provides the capability to optimize applications involving trade-offs between gate charge and conduction losses. An advanced adaptive shoot-through protection is integrated to prevent both the upper and lower MOSFETs from conducting simultaneously and to minimize dead time. The RAA220001 has a 10kΩ integrated high-side gate-to-source resistor to prevent self turn-on due to high input bus dV/dt. This driver also has an overvoltage protection feature that is operational while VCC is below the POR threshold. The PHASE node is connected to the gate of the low-side MOSFET (LGATE) through a 30kΩ resistor, limiting the output voltage of the converter close to the gate threshold of the low-side MOSFET. This design is dependent on the current being shunted, which provides some protection to the load should the upper MOSFET(s) become shorted.