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19-3357; Rev 0; 8/04
Dual-Phase MOSFET Driverswww.DataSheet4U.com
with Temperature Sensor
General Description
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.
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.
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.
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.
Features
o Dual-Phase MOSFET Driver
o 0.35(typ) On-Resistance and 5A (typ)
Drive Current
o Drives Large Synchronous-Rectifier MOSFETs
o Integrated Temperature Sensor (MAX8702 Only)
Resistor Programmable
Open-Drain Driver Hot Indicator (DRHOT)
o Adaptive Dead Time Prevents Shoot-Through
o Selectable Pulse-Skipping Mode
o 4.5V to 28V Input Voltage Range
o Thermally Enhanced Low-Profile Thin QFN Package
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
DESCRIPTION
MAX8702ETP
-40°C to +100°C
20 Thin QFN
4mm x 4mm
Dual-Phase
Driver with
Temp. Sensor
Dual-Phase
MAX8703ETP
-40°C to +100°C
20 Thin QFN
4mm x 4mm
Driver without
Temp. Sensor
Minimal Operating Circuit
Applications
Multiphase High-Current Power Supplies
2- to 4-Cell Li+ Battery to CPU Core Supplies
Notebook and Desktop Computers
Servers and Workstations
+5V
Pin Configuration appears at end of data sheet.
VDD
VCC
AGND
TSET
BST1
DH1
LX1
DL1
PGND1
MAX8702
BST2
DRHOT
SHDN
SKIP
PWM1
PWM2
DH2
LX2
DL2
PGND2
+5V
+5V
VIN
4.5V TO 28V
VOUT
VIN
4.5V TO 28V
VOUT
________________________________________________________________ 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.

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ABSOLUTE MAXIMUM RATINGS
VCC to AGND............................................................-0.3V to +6V
VDD to AGND............................................................-0.3V to +6V
PGND_ to AGND ...................................................-0.3V to +0.3V
SKIP, SHDN, DRHOT, TSET to AGND......................-0.3V to +6V
PWM_ to AGND ........................................................-0.3V to +6V
DL_ to PGND_ ............................................-0.3V to (VDD + 0.3V)
LX_ to AGND .............................................................-2V to +30V
DH_ to LX_ ...............................................-0.3V to (VBST_ + 0.3V)
BST_ to LX_ ..............................................................-0.3V to +6V
Continuous Power Dissipation (TA = +70°C)
20-Pin 4mm x 4mm Thin QFN
(derate 16.9mW/°C above +70°C) .............................1349mW
Operating Temperature Range .........................-40°C to +100°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 2. VCC = VDD = VSHDN = VSKIP = 5V, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
Input Voltage Range
VCC
VCC Undervoltage-Lockout
Threshold
VCC Quiescent Current
(Note 1)
VDD Quiescent Current
VCC Shutdown Current
VDD Shutdown Current
VUVLO
ICC
IDD
85mV typical VCC rising
hysteresis
VCC falling
SKIP = AGND, PWM_ = AGND
SKIP = AGND, PWM_ = VCC
SKIP = AGND, PWM_ = AGND
SHDN = SKIP = AGND
SHDN = SKIP = AGND
GATE DRIVERS AND DEAD-TIME CONTROL (Figure 1)
DL_ Propagation Delay
tPWM-DL
tDH-DL
PWM_ high to DL_ low
DH_ low to DL_ high
DH_ Propagation Delay
tDL-DH
tPWM-DH
DL_ low to DH_ high
PWM_ low to DH_ low
DL_ Transition Time
tF_DL
tR_DL
DL_ falling, 3nF load
DL_ rising, 3nF load
DH_ Transition Time
tF_DH
tR_DH
DH_ falling, 3nF load
DH_ rising, 3nF load
DH_ On-Resistance (Note 2)
RDH
VBST_ - VLX_ = 5V
DL_ On-Resistance (Note 2)
RDL_HIGH High state (pullup)
RDL_LOW Low state (pulldown)
DH_ Source/Sink Current
IDH VDH_ = 2.5V, VBST_ - VLX_ = 5V
DL_ Source Current
IDL_SOURCE VDL_ = 2.5V
DL_ Sink Current
Zero-Crossing Threshold
IDL_SINK
VDL_ = 5V
VPGND_ - VLX_, SKIP = AGND
TEMPERATURE SENSOR
Temperature Threshold
Accuracy
DRHOT Output Low Voltage
DRHOT Leakage Current
TA = +85°C to +125°C, 10°C falling hysteresis
ISINK = 3mA
High state, VDRHOT = 5.5V
MIN
4.5
3.4
3.3
-5
TYP
3.85
3.75
200
2
1
2
1
MAX
5.5
4.1
4.0
400
3
5
5
5
UNITS
V
V
µA
mA
µA
µA
µA
19
36
25
23
11
8
14
16
1.0
1.0
0.35
1.5
1.5
5
2.5
4.5
4.5
2.0
ns
ns
ns
ns
A
A
A
mV
+5 °C
0.4 V
1 µA
2 _______________________________________________________________________________________

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Dual-Phase MOSFET Driverswww.DataSheet4U.com
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ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 2. VCC = VDD = VSHDN = VSKIP = 5V, TA = 0°C to +85°C. Typical values are at TA = +25°C, unless otherwise noted.)
PARAMETER
Thermal-Shutdown Threshold
LOGIC CONTROL SIGNALS
Logic Input High Voltage
Logic Input Low Voltage
Logic Input Current
SYMBOL
CONDITIONS
10°C hysteresis
SHDN, SKIP, PWM1, PWM2
SHDN, SKIP, PWM1, PWM2
SHDN, SKIP, PWM1, PWM2
MIN TYP MAX UNITS
+160
°C
2.4 V
0.8 V
-1 +1 µA
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 2. VCC = VDD = VSHDN = VSKIP = 5V, TA = -40°C to +100°C, unless otherwise noted.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
Input Voltage Range
VCC
4.5 5.5 V
VCC Undervoltage-Lockout
Threshold
VCC Quiescent Current
VUVLO
ICC
85mV typical VCC rising
hysteresis
VCC falling
SKIP = AGND, PWM_ = PGND_
SKIP = AGND, PWM_ = VCC
3.4 4.1
V
3.3 4.0
450 µA
3 mA
VDD Quiescent Current
VCC Shutdown Current
VDD Shutdown Current
IDD
SKIP = AGND, PWM_ = PGND_,
TA = -40°C to +85°C
SHDN = SKIP = AGND, TA = -40°C to +85°C
SHDN = SKIP = AGND, TA = -40°C to +85°C
5 µA
5 µA
5 µA
GATE DRIVERS AND DEAD-TIME CONTROL
DH_ On-Resistance (Note 2)
RDH
VBST_ - VLX_ = 5V
1.0 4.5
DL_ On-Resistance (Note 2)
RDL _HIGH High state (pullup)
RDL _LOW Low state (pulldown)
1.0 4.5
0.35 2.0
TEMPERATURE SENSOR
DRHOT Output Low Voltage
ISINK = 3mA
0.4 V
LOGIC CONTROL SIGNALS
Logic Input High Voltage
Logic Input Low Voltage
SHDN, SKIP, PWM1, PWM2
SHDN, SKIP, PWM1, PWM2
2.4 V
0.8 V
Note 1: Static drivers instead of pulsed-level translators.
Note 2: Production testing limitations due to package handling require relaxed maximum on-resistance specifications for the
thin QFN package.
Note 3: Specifications from -40°C to +100°C are guaranteed by design, not production tested.
_______________________________________________________________________________________ 3

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Dual-Phase MOSFET Drivers
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PWM_
DH_
DL_
90%
tPWM-DL
tF_DL
90%
10%
tDL-DH
tR_DH
10%
90%
tPWM-DH
tF_DH
10%
tDH-DL
tR_DL
90%
10%
Figure 1. Timing Definitions Used in the Electrical Characteristics
Typical Operating Characteristics
(Circuit of Figure 2. VIN = 12V, VDD = VCC = VSHDN = VSKIP = 5V, TA = +25°C unless otherwise noted.)
POWER DISSIPATION vs. FREQUENCY
(SINGLE PHASE, BOTH DRIVERS SWITCHING)
350
300 CDL = 6nF, CDH = 3nF
250
200 CDL = 3nF, CDH = 3nF
150
100
50
0
0
CDL = 3nF,
CDH = 1.5nF
VCC = 5.5V
0.2 0.4 0.6 0.8 1.0 1.2
FREQUENCY (MHz)
POWER DISSIPATION vs. CAPACITIVE LOAD
(SINGLE PHASE, BOTH DRIVERS SWITCHING)
400
FREQ = 1.2MHz
300
FREQ = 0.6MHz
200
100
0
1
FREQ = 0.3MHz
VCC = 5.5V,
CDH = CDL
234
CAPACITANCE (nF)
5
6
DL RISE/FALL TIME vs. CAPACITIVE LOAD
20
DH RISE/FALL TIME vs. CAPACITIVE LOAD
30
15 DL RISE
25
DH RISE
20
10
DL FALL
5
15
DH FALL
10
5
0
123456
CAPACITANCE (nF)
0
123456
CAPACITANCE (nF)
4 _______________________________________________________________________________________

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Dual-Phase MOSFET Driverswww.DataSheet4U.com
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Typical Operating Characteristics (continued)
(Circuit of Figure 2. VIN = 12V, VDD = VCC = VSHDN = VSKIP = 5V, TA = +25°C unless otherwise noted.)
DH/DL RISE/FALL TIMES
vs. TEMPERATURE
20
DH RISE DH FALL
15
10
DL RISE
5 DL FALL
CDH = CDL = 3nF
0
0 20 40 60 80 100 120
TEMPERATURE (°C)
PROPAGATION DELAY vs. TEMPERATURE
50
DL FALL TO DH RISE
40
PWM FALL TO DH FALL
30
20
10
0
0
PWM RISE TO DL FALL
CDH = CDL = 3nF
30 60 90 120
TEMPERATURE (°C)
150
70
60
50
40
30
20
10
0
50
RTSET vs. TEMPERATURE
70 90 110 130
TEMPERATURE (°C)
150
DH RISE AND DL FALL WAVEFORMS
MAX8702 toc09
5V
A
0
5V
B
0
10V C
0
D
0
TYPICAL SWITCHING WAVEFORMS
MAX8702 toc08
5V
A
0
5V
B
0
10V
0C
0D
A. PWM, 5V/div
B. DL, 5V/div
125ns/div
C. DH, 10V/div
D. LX, 10V/div
DH FALL AND DL RISE WAVEFORMS
MAX8702 toc10
5V
A
0
5V
B
0
10V
C
0
0D
A. PWM, 5V/div
B. DL, 5V/div
20ns/div
C. DH, 10V/div
D. LX, 10V/div
A. PWM, 5V/div
B. DL, 5V/div
20ns/div
C. DH, 10V/div
D. LX, 10V/div
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