RT9619/RT9619A

Description

The RT9619/A is a high frequency, dual MOSFET driver specifically designed to drive two power N-Channel MOSFETs in a synchronous-rectified buck converter topology. This driver is combined with Richtek's series of Multi-Phase Buck PWM controller to form a complete core-voltage regulator solution for advanced micro-processors.
The RT9619/A drives both the lower/upper gate in a synchronous-rectifier bridge with 12V. This drive-voltage flexibility provides the advantage of optimizing applications involving trade-offs between switching losses and conduction losses.
The RT9619A has longer UGATE/LGATE deadtime which can drive the MOSFETs with large gate RC value, avoiding the shoot-through phenomenon. The RT9619 is targeted to drive low gate RC MOSFETs and performs better efficiency.
The output drivers in the RT9619/A can efficiently switch power MOSFETs at frequency up to 500kHz. Switching frequency above 500kHz has to take into account the thermal dissipation of SOP-8 package. RT9619/A is capable to drive a 3nF load with a 30ns rise time. The RT9619/A implements bootstrapping on the upper gate with an external capacitor and an embedded diode. This reduces implementation complexity and allows the use of higher performance, cost effective N-Channel MOSFETs. Adaptive shoot-through protection is integrated to prevent both MOSFETs from conducting simultaneously.