Dual Bootstrapped 12 V
MOSFET Driver with Output Disable
ADP3118
FEATURES
GENERAL DESCRIPTION
Optimized for low gate charge MOSFETs
All-in-one synchronous buck driver
Bootstrapped high-side drive
One PWM signal generates both drives
Anticross-conduction protection circuitry
Output disable control turns off both MOSFETs to float
output per Intel VRM 10
The ADP3118 is a dual, high voltage MOSFET driver optimized
for driving two N-channel MOSFETs, which are the two switches
in a nonisolated synchronous buck power converter. Each of the
drivers is capable of driving a 3000 pF load with a 25 ns prop-
agation delay and a 25 ns transition time. One of the drivers can
be bootstrapped and is designed to handle the high voltage slew
rate associated with floating high-side gate drivers. The ADP3118
includes overlapping drive protection to prevent shoot-through
current in the external MOSFETs.
Meets CPU VR requirement when used with
Analog Devices, Inc. Flex-Mode1 controller
The OD pin shuts off both the high-side and the low-side
MOSFETs to prevent rapid output capacitor discharge during
system shutdown.
APPLICATIONS
Multiphase desktop CPU supplies
Single-supply synchronous buck converters
The ADP3118 is specified over the commercial temperature
range of 0°C to 85°C and is available in 8-lead SOIC and 8-lead
LFCSP packages.
SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM
V
12V
IN
D1
VCC
4
BST
ADP3118
1
8
C
BST2
C
BST1
2
R
G
IN
DRVH
Q1
DELAY
R
BST
TO
INDUCTOR
SW
7
CMP
VCC
6
CMP
DRVL
PGND
1V
CONTROL
LOGIC
5
6
Q2
DELAY
3
OD
Figure 1.
1Flex-Mode™ is protected by U.S. Patent 6683441.
©2008 SCILLC. All rights reserved.
January 2008 – Rev. 2
Publication Order Number:
ADP3118/D