The RT9603 is a high frequency, dual MOSFET drivers
specifically designed to drive two power N-Channel
MOSFETs in a synchronous-rectified buck converter
topology. The device combined with the RT924x series
of multi-phase PWM controllers and MOSFETs form a
complete core voltage regulator solution for advanced
microprocessors.
The output drivers in the RT9603 can efficiently switch
power MOSFETs at frequencies up to 500kHz. It shall be
taken into account the thermal consideration when the
switching frequency above 500kHz. Each driver is
capable of driving a 3nF load in 30/40ns rise/fall time with
fast propagation delay from input transition to the gate of
the power MOSFET. The device implements bootstrapping
on the upper gate with only an external capacitor
and a diode required. This reduces implementation
complexity and allows the use of higher performance,
cost effective N-Channel MOSFETs.
Both drivers incorporate adaptive shoot-through protection
to prevent upper and lower MOSFETs from conducting
simultaneously and shorting the input supply.
An unique feature of the RT9603 driver is the addition of
over-voltage protection in the event of upper MOSFET
direct shorted before power-on. The RT9603 detects the
fault condition during initial start-up, the internal poweron
OVP sense circuitry will rapidly drive the output lower
MOSFET on before the multi-phase PWM controller takes
control. As a result, the input supply will latch into the
shutdown state, thereby prevent the processor from
damaged.