19-3357; Rev 0; 8/04
Dual-Phase MOSFET Drivers
with Temperature Sensor
General Description
Features
The MAX8702/MAX8703 dual-phase noninverting
MOSFET drivers are designed to work with PWM con-
troller ICs, such as the MAX8705/MAX8707, in note-
book CPU core and other multiphase regulators.
Applications can either step down directly from the bat-
tery voltage to create the core voltage, or step down
from a low-voltage system supply. The single-stage con-
version method allows the highest possible efficiency,
while the 2-stage conversion at higher switching frequen-
cy provides the minimum possible physical size.
ꢀ Dual-Phase MOSFET Driver
ꢀ 0.35Ω (typ) On-Resistance and 5A (typ)
Drive Current
ꢀ Drives Large Synchronous-Rectifier MOSFETs
ꢀ Integrated Temperature Sensor (MAX8702 Only)
Resistor Programmable
Open-Drain Driver Hot Indicator (DRHOT)
ꢀ Adaptive Dead Time Prevents Shoot-Through
ꢀ Selectable Pulse-Skipping Mode
Each MOSFET driver is capable of driving 3nF capaci-
tive loads with only 19ns propagation delay and 8ns
typical rise and fall times. Larger capacitive loads are
allowable but result in longer propagation and transition
times. Adaptive dead-time control helps prevent shoot-
through currents and maximizes converter efficiency.
ꢀ 4.5V to 28V Input Voltage Range
ꢀ Thermally Enhanced Low-Profile Thin QFN Package
Ordering Information
The MAX8702/MAX8703 feature zero-crossing com-
parators on each channel. When enabled, these com-
parators permit the drivers to be used in pulse-skipping
operation, thereby saving power at light loads. A sepa-
rate shutdown control is also included that disables all
functions, drops quiescent current to 2µA, and sets DH
low and DL high.
PIN-
PACKAGE
PART
TEMP RANGE
DESCRIPTION
Dual-Phase
Driver with
Temp. Sensor
20 Thin QFN
4mm x 4mm
MAX8702ETP -40°C to +100°C
MAX8703ETP -40°C to +100°C
Dual-Phase
Driver without
Temp. Sensor
The MAX8702 integrates a resistor-programmable tem-
perature sensor. An open-drain output (DRHOT) signals
to the system when the local die temperature exceeds
the set temperature. The MAX8702/MAX8703 are avail-
able in a thermally-enhanced 20-pin thin QFN package.
20 Thin QFN
4mm x 4mm
Minimal Operating Circuit
+5V
Applications
V
IN
V
+5V
BST1
DH1
DD
4.5V TO 28V
Multiphase High-Current Power Supplies
2- to 4-Cell Li+ Battery to CPU Core Supplies
Notebook and Desktop Computers
Servers and Workstations
V
CC
V
LX1
DL1
OUT
AGND
TSET
PGND1
+5V
MAX8702
V
IN
BST2
4.5V TO 28V
DH2
DRHOT
SHDN
V
LX2
DL2
OUT
SKIP
PWM1
PWM2
PGND2
Pin Configuration appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.