RT9619/A
Synchronous-Rectified Buck MOSFET Drivers
General 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 combined with Richtek's series of
Multi-Phase Buck PWM controller 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.
RT9619A has longer UGATE/LGATE deadtime which can
drive the MOSFETs with large gate RC value, avoiding the
shoot-through phenomenon. 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.
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.
Features
Drives Two N-Channel MOSFETs
Adaptive Shoot-Through Protection
Embedded Boot Strapped Diode
Supports High Switching Frequency
Fast Output Rise Time
Small SOP-8 Package
Tri-State Input for Bridge Shutdown
Supply Under Voltage Protection
Upper MOSFET Direct Shorted Protection
RoHS Compliant and 100% Lead (Pb)-Free
Applications
Core Voltage Supplies for Desktop, Motherboard CPU
High Frequency Low Profile DC-DC Converters
High Current Low Voltage DC-DC Converters
Ordering Information
RT9619/A
Package Type
S : SOP-8
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Long Dead Time
Short Dead Time
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)
BOOT
PWM
NC
VCC
2
3
4
8
7
6
5
UGATE
PHASE
PGND
LGATE
SOP-8
DS9619/A-04 March 2007
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
