资 源 简 介
The PX3511x is a high frequency MOSFET driver specificallydesigned to drive upper and lower power N-channelMOSFETs in a synchronous recTIfied buck converter topology.These drivers combined with the PX3535 or PX3538 DigitalMulTI-phase Controllers and N-channel MOSFETs form acomplete core-voltage regulator soluTIon for advancedmicroprocessors.The PX3511A drives the upper gate to +12V, while the lowergate can be independently driven over a range from +5V to+12V. The PX3511B and PX3511D drive both upper andlower gates over a range of +5V to +12V. This drive-voltageprovides the flexibility needed to opTImize applicationsinvolving trade-offs between gate charge and conductionlosses.Adaptive zero shoot-through protection is integrated into thePX3511x to minimize dead time and prevent both upper andlower MOSFETs from conducting simultaneously. An overvoltageprotection feature is operational before VCC exceedsits turn-on threshold, where the PHASE node is connected tothe gate of the low-side MOSFET (LGATE). The outputvoltage of the converter is then limited by the threshold of thelow-side MOSFET. This protects the microprocessor if theupper MOSFET is shorted during initial startup.The PX3511x also features a three-state PWM input that,when used together with Primarion’s Digital MultiphaseControllers, prevents a negative transient on the outputvoltage when the output is shut down. This feature eliminatesthe need for Schottky diodes that are used to protect the loadfrom reverse output voltage events.
