
Dual-Phase MOSFET Drivers
with Temperature Sensor
Typical Operating Circuit
The typical operating circuit of the MAX8702 ( Figure 2)
shows the power-stage and gate-driver circuitry of a dual-
phase CPU core supply operating at 300kHz, with each
phase capable of supplying 20A of load current. Table 1
lists recommended component options, and Table 2 lists
the component suppliers ’ contact information.
regulators. Each MOSFET driver is capable of driving
3nF capacitive 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 pre-
vents shoot-through currents and maximizes converter
Detailed Description
+5V
D BST1
The MAX8702/MAX8703 dual-phase noninverting
MOSFET drivers are intended to work with PWM con-
troller ICs in CPU core and other multiphase switching
Table 1. Component List
DESIGNATION
DESCRIPTION
2.2 μ F
10 ?
1 μ F
R TSET
V DD
V CC
AGND
BST1
DH1
LX1
DL1
0.22 μ F
NH1
NL1
C IN1
D1
V IN
7V TO 20V
L1
V OUT
C OUT1
PGND1
Total Input
Capacitance (C IN )
(4) 10μF, 25V
Taiyo Yuden TMK432BJ106KM or
TDK C4532X5R1E106M
+5V
100k ?
TSET
MAX8702
D BST2
+5V
Total Output
Capacitance (C OUT )
(4) 330μF, 2.5V, 9m ? low-ESR polymer
capacitor (D case)
Sanyo 2R5TPE330M9
DRSKP
DRHOT
SHDN
SKIP
BST2
DH2
0.22 μ F
NH2
C IN2
V IN
7V TO 20V
L2
Schottky Diode
(per phase)
3A Schottky diode
Central Semiconductor
CMSH3-40
FROM
CONTROLLER
IC
PWM1
PWM2
PWM1
PWM2
LX2
DL2
NL2
D2
V OUT
C OUT2
PGND2
0.6μH
Inductor (per phase)
Panasonic ETQP1H0R6BFA or
Sumida CDEP134H-0R6
Figure 2. MAX8702 Typical Operating Circuit
High-Side MOSFET
Siliconix (1) Si7892DP or
(NH, per phase)
International Rectifier (2) IRF6604
TSET*
TEMP
Low-Side MOSFET
(NL, per phase)
Siliconix (2) Si7442DP or
International Rectifier (2) IRF6603
DRHOT*
SENSOR +
TSDN
PWM BLOCK (x2)
BST_
V CC
DH_
Table 2. Component Suppliers
AGND
UVLO
LX_
SUPPLIER
Central Semiconductor
Fairchild Semiconductor
International Rectifier
WEBSITE
www.centralsemi.com
www.fairchildsemi.com
www.irf.com
PWM_
SHDN
CONTROL
AND ADAPTIVE
DEAD-TIME
CIRCUIT
MAX8702
MAX8703
V DD
Panasonic
www.panasonic.com
Sanyo
www.secc.co.jp
LX_
DL_
Siliconix (Vishay)
Sumida
www.vishay.com
www.sumida.com
SKIP
PGND_
ZX
PGND_
Taiyo Yuden
www.t-yuden.com
TDK
www.component.tdk.com
*MAX8702 ONLY
Figure 3. MAX8702 Functional Diagram
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