The PX3511x is a high frequency MOSFET driver specifically designed to drive upper and lower power N-channel MOSFETs in a synchronous rectified buck converter topology. These drivers combined with the PX3535 or PX3538 Digital Multi-phase Controllers and N-channel MOSFETs form a complete core-voltage regulator solution for advanced microprocessors. The PX3511A drives the upper gate to +12V, while the lower gate can be independently driven over a range from +5V to +12V. The PX3511B and PX3511D drive both upper and lower gates over a range of +5V to +12V. This drive-voltage provides the flexibility needed to optimize applications involving trade-offs between gate charge and conduction losses. Adaptive zero shoot-through protection is integrated into the PX3511x to minimize dead time and prevent both upper and lower MOSFETs from conducting simultaneously. An overvoltage protection feature is operational before VCC exceeds its turn-on threshold, where the PHASE node is connected to the gate of the low-side MOSFET (LGATE). The output voltage of the converter is then limited by the threshold of the low-side MOSFET. This protects the microprocessor if the upper MOSFET is shorted during initial startup. The PX3511x also features a three-state PWM input that, when used together with Primarion’s Digital Multiphase Controllers, prevents a negative transient on the output voltage when the output is shut down. This feature eliminates the need for Schottky diodes that are used to protect the load from reverse output voltage events.