LTC7802 40V Low I , 3MHz Dual, 2-Phase Synchronous Q Step-Down Controller with Spread Spectrum FEATURES DESCRIPTION n Wide Input Voltage Range: 4.5V to 40V The LTC 7802 is a high performance dual step-down n Wide Output Voltage Range: 0.8V to 99% V synchronous DC/DC switching regulator controller that IN n Low Operating I : 14A (14V to 3.3V, Channel 1 On) drives all N-channel power MOSFET stages. Constant fre- Q n Spread Spectrum Operation quency current mode architecture allows a phase-lockable n R or DCR Current Sensing switching frequency of up to 3MHz. The LTC7802 oper- SENSE n Out-of-Phase Controllers Reduce Required Input ates from a wide 4.5V to 40V input supply range. Power Capacitance and Power Supply Induced Noise loss and supply noise are minimized by operating the two n Programmable Fixed Frequency (100kHz to 3MHz) controller output stages out-of-phase. n Phase-Lockable Frequency (100kHz to 3MHz) The very low no-load quiescent current extends oper- n Selectable Continuous, Pulse-Skipping, or Low ating runtime in battery powered systems. OPTI-LOOP Ripple, Burst Mode Operation at Light Loads compensation allows the transient response to be opti- n Very Low Dropout Operation: 99% Duty Cycle mized over a wide range of output capacitance and ESR n Power Good Output Voltage Monitors values. The LTC7802 features a precision 0.8V reference n Output Overvoltage Protection and power good output indicators. The MODE pin selects n Internal LDO Powers Gate Drive from V or EXTV IN CC among Burst Mode operation, pulse-skipping mode, or n Low Shutdown I : 1.5A Q continuous inductor current mode at light loads. n Small 28-Lead 4mm 5mm QFN Package The LTC7802 additionally features spread spectrum oper- ation which significantly reduces the peak radiated and conducted noise on both the input and output supplies, APPLICATIONS making it easier to comply with electromagnetic interfer- n Automotive and Transportation ence (EMI) standards. n Industrial All registered trademarks and trademarks are the property of their respective owners. n Military/Avionics TYPICAL APPLICATION INTV CC V IN 4.5V TO 40V 4.7F RUN1 V RUN2 INTV IN CC BOOST1 BOOST2 TG1 TG2 0.9H 0.1F 0.1F 1.8H SW1 SW2 LTC7802 BG1 BG2 + + SENSE1 SENSE2 3m 2m SENSE1 SENSE2 V OUT1 V OUT2 3.3V/12A EXTV CC 5V/10A 210k 357k 330F 220F V V FB1 FB2 ITH1 ITH2 68.1k TRACK/SS1 TRACK/SS2 68.1k MODE PLLIN/SPREAD 0.1F 0.1F FREQ GND 7802 TA01a Rev. 0 1 Document Feedback For more information www.analog.comLTC7802 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) Input Supply Voltage (V ) ......................... 0.3V to 40V IN TOP VIEW BOOST1, BOOST2 ...................................... 0.3V to 46V Switch Voltage (SW1, SW2) .......................... 5V to 40V RUN1, RUN2 Voltages ................................ 0.3V to 40V EXTV Voltage ......................................... 0.3V to 30V CC 28 27 26 25 24 23 + INTV Voltage ............................................ 0.3V to 6V CC SENSE1 1 22 SW1 (BOOST1SW1), (BOOST2SW2) ................ 0.3V to 6V SENSE1 2 21 BOOST1 + FREQ 3 20 BG1 SENSE1 , SENSE1 Voltages ...................... 0.3V to 40V + MODE 4 GND 19 V IN SENSE2 , SENSE2 Voltages ..................... 0.3V to 40V 29 RUN1 5 18 EXTV CC TRACK/SS1, V Voltages .......................... 0.3V to 6V FB1 RUN2 6 17 INTV CC TRACK/SS2, V Voltages .......................... 0.3V to 6V FB2 SENSE2 7 16 BG2 MODE, PGOOD1, PGOOD2 Voltages ............ 0.3V to 6V + SENSE2 8 15 BOOST2 9 10 11 12 13 14 PLLIN/SPREAD, FREQ Voltages ................... 0.3V to 6V ITH1, ITH2 Voltages ..................................... 0.3V to 2V BG1, BG2, TG1, TG2 ........................................... (Note 9) Operating Junction Temperature Range (Notes 2, 8) UFDM PACKAGE LTC7802E, LTC7802I ......................... 40C to 125C 28-LEAD (4mm 5mm) PLASTIC QFN T = 150C, = 43C/W JMAX JA LTC7802J, LTC7802H ........................ 40C to 150C EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB Storage Temperature Range .................. 65C to 150C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC7802EUFDM PBF LTC7802EUFDM TRPBF 7802 28-Lead (4mm 5mm) Plastic QFN 40C to 125C AUTOMOTIVE PRODUCTS** LTC7802IUFDM WPBF LTC7802IUFDM WTRPBF 7802 28-Lead (4mm 5mm) Plastic QFN 40C to 125C LTC7802JUFDM WPBF LTC7802JUFDM WTRPBF 7802 28-Lead (4mm 5mm) Plastic QFN 40C to 150C LTC7802HUFDM WPBF LTC7802HUFDM WTRPBF 7802 28-Lead (4mm 5mm) Plastic QFN 40C to 150C Contact the factory for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Tape and reel specifications. Some packages are available in 500 unit reels through designated sales channels with TRMPBF suffix. **Versions of this part are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. These models are designated with a W suffix. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for thesemodels. Rev. 0 2 For more information www.analog.com V V FB2 FB1 ITH1 ITH2 TRACK/SS2 TRACK/SS1 PGOOD2 PLLIN/SPREAD TG2 PGOOD1 SW2 TG1