MAX8702/MAX8703 19-3357 Rev 0 8/04 Dual-Phase MOSFET Drivers with Temperature Sensor General Description Features The MAX8702/MAX8703 dual-phase noninverting Dual-Phase MOSFET Driver MOSFET drivers are designed to work with PWM con- 0.35 (typ) On-Resistance and 5A (typ) troller ICs, such as the MAX8705/MAX8707, in note- Drive Current book CPU core and other multiphase regulators. Drives Large Synchronous-Rectifier MOSFETs Applications can either step down directly from the bat- tery voltage to create the core voltage, or step down Integrated Temperature Sensor (MAX8702 Only) from a low-voltage system supply. The single-stage con- Resistor Programmable version method allows the highest possible efficiency, Open-Drain Driver Hot Indicator (DRHOT) while the 2-stage conversion at higher switching frequen- Adaptive Dead Time Prevents Shoot-Through cy provides the minimum possible physical size. Selectable Pulse-Skipping Mode Each MOSFET driver is capable of driving 3nF capaci- 4.5V to 28V Input Voltage Range tive loads with only 19ns propagation delay and 8ns typical rise and fall times. Larger capacitive loads are Thermally Enhanced Low-Profile Thin QFN Package allowable but result in longer propagation and transition times. Adaptive dead-time control helps prevent shoot- through currents and maximizes converter efficiency. Ordering Information The MAX8702/MAX8703 feature zero-crossing com- PIN- parators on each channel. When enabled, these com- PART TEMP RANGE D ESCR IPTIO N PACKAGE parators permit the drivers to be used in pulse-skipping operation, thereby saving power at light loads. A sepa- Dual-Phase rate shutdown control is also included that disables all 20 Thin Q FN MAX8702ETP -40C to +100C Driver with functions, drops quiescent current to 2A, and sets DH 4m m x 4mm Temp. Sensor low and DL high. Dual-Phase The MAX8702 integrates a resistor-programmable tem- 20 Thin Q FN MAX8703ETP -40C to +100C Driver without perature sensor. An open-drain output (DRHOT) signals 4m m x 4mm Temp. Sensor 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. Minimal Operating Circuit +5V Applications V IN +5V V DD BST1 4.5V TO 28V Multiphase High-Current Power Supplies DH1 2- to 4-Cell Li+ Battery to CPU Core Supplies V CC V LX1 OUT Notebook and Desktop Computers AGND DL1 Servers and Workstations PGND1 TSET +5V MAX8702 V IN BST2 4.5V TO 28V DH2 DRHOT SHDN V LX2 OUT SKIP DL2 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 Maxims website at www.maxim-ic.com.Dual-Phase MOSFET Drivers with Temperature Sensor ABSOLUTE MAXIMUM RATINGS V to AGND............................................................-0.3V to +6V BST to LX ..............................................................-0.3V to +6V CC V to AGND............................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) DD A PGND to AGND ...................................................-0.3V to +0.3V 20-Pin 4mm x 4mm Thin QFN SKIP, SHDN, DRHOT, TSET to AGND......................-0.3V to +6V (derate 16.9mW/C above +70C).............................1349mW PWM to AGND........................................................-0.3V to +6V Operating Temperature Range .........................-40C to +100C DL to PGND ............................................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C DD LX to AGND .............................................................-2V to +30V Storage Temperature Range .............................-65C to +150C DH to LX ...............................................-0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) .................................+300C BST 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. V = V = V = V = 5V, T = 0C to +85C. Typical values are at T = +25C, unless otherwise noted.) CC DD SHDN SKIP A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage Range V 4.5 5.5 V CC V rising 3.4 3.85 4.1 CC V Undervoltage-Lockout 85mV typical CC V V UVLO Threshold hysteresis V falling 3.3 3.75 4.0 CC SKIP = AGND, PWM = AGND 200 400 A V Quiescent Current CC I CC (Note 1) SKIP = AGND, PWM = V 23 mA CC V Quiescent Current I SKIP = AGND, PWM = AGND 1 5 A DD DD V Shutdown Current SHDN = SKIP = AGND 2 5 A CC V Shutdown Current SHDN = SKIP = AGND 1 5 A DD GATE DRIVERS AND DEAD-TIME CONTROL (Figure 1) t PWM high to DL low 19 PWM-DL DL Propagation Delay ns t DH low to DL high 36 DH-DL t DL low to DH high 25 DL-DH DH Propagation Delay ns t PWM low to DH low 23 PWM-DH t DL falling, 3nF load 11 F DL DL Transition Time ns t DL rising, 3nF load 8 R DL t DH falling, 3nF load 14 F DH DH Transition Time ns t DH rising, 3nF load 16 R DH DH On-Resistance (Note 2) R V - V = 5V 1.0 4.5 DH BST LX R High state (pullup) 1.0 4.5 DL HIGH DL On-Resistance (Note 2) R Low state (pulldown) 0.35 2.0 DL LOW DH Source/Sink Current I V = 2.5V, V - V = 5V 1.5 A DH DH BST LX DL Source Current I V = 2.5V 1.5 A DL SOURCE DL DL Sink Current I V = 5V 5 A DL SINK DL Zero-Crossing Threshold V - V , SKIP = AGND 2.5 mV PGND LX TEMPERATURE SENSOR Temperature Threshold T = +85C to +125C, 10C falling hysteresis -5 +5 C A Accuracy DRHOT Output Low Voltage I = 3mA 0.4 V SINK DRHOT Leakage Current High state, V = 5.5V 1 A DRHOT 2 MAX8702/MAX8703