RT9603
Synchronous-Rectified Buck MOSFET Drivers
General Description
The RT9603 is a high frequency, dual MOSFET drivers
specifically designed to drive two power N-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 boot-strapping 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-
MOSFETs.
Both drivers incorporate adaptive shoot-through protect-
ion to prevent upper and lower MOSFETs from conduct-
ing 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 power-
on 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.
Features
Drives Two N-MOSFETs
Adaptive Shoot-Through Protection
Supports High Switching Frequency
Fast Output Rise Time
Propagation Delay 40ns
Tri-State Input for Bridge Shutdown
Supply Over-Voltage Protection above Maximum
Voltage Rating
Supply Under-Voltage Protection
Upper MOSFET Direct Shorted Protection
Small SOP-8 Package
RoHS Compliant and 100% Lead (Pb)-Free
Applications
Core Voltage Supplies for Intel Pentium
®
4, AMD
®
Athlon
TM
Microprocessors
High Frequency Low Profile DC-DC Converters
High Current Low Voltage DC-DC Converters
IA Equipments
Ordering Information
RT9603
Package Type
S : SOP-8
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Note :
RichTek Pb-free and Green products are :
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
100%matte tin (Sn) plating.
Pin Configurations
(TOP VIEW)
BST
VIN
NC
VCC
2
3
4
8
7
6
5
DRVH
SW
PGND
DRVL
SOP-8
DS9603-08 March 2007
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
