LTC7805 40V Low I , Dual, 2-Phase Q 100% Duty Cycle Synchronous Step-Down Controller FEATURES DESCRIPTION n Wide Input Voltage Range: 4.5V to 40V The LTC 7805 is a high performance dual step-down n Wide Output Voltage Range: 0.8V to 40V synchronous DC/DC switching regulator controller that n Low Operating I drives all N-channel power MOSFET stages. Constant fre- Q n 14A (14V to 3.3V, Channel 1 On) quency current mode architecture allows a phase-lockable n PassThru/100% Duty Cycle Capable switching frequency of up to 3MHz. The LTC7805 oper- n Spread Spectrum Operation ates from a wide 4.5V to 40V input supply range. Power n R or DCR Current Sensing loss and supply noise are minimized by operating the two SENSE n Out-of-Phase Controllers Reduce Required Input controller output stages out-of-phase. Capacitance and Power Supply Induced Noise The very low no-load quiescent current extends oper- n Programmable Fixed Frequency (100kHz to 3MHz) ating runtime in battery powered systems. OPTI-LOOP n Phase-Lockable Frequency (100kHz to 3MHz) compensation allows the transient response to be opti- n Selectable Continuous, Pulse-Skipping, or Low mized over a wide range of output capacitance and ESR Ripple, Burst Mode Operation at Light Loads values. The LTC7805 features a precision 0.8V reference n Power Good Output Voltage Monitors 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 Side Wettable 28-Lead 4mm 5mm QFN Package n The LTC7805 additionally features spread spectrum oper- AEC-Q100 Automotive Qualification in Process 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 TG2 TG1 0.9H 0.1F 0.1F 1.8H SW1 SW2 LTC7805 BG1 BG2 + + SENSE1 SENSE2 3m 2m SENSE1 SENSE2 V OUT1 V OUT2 EXTV 3.3V/12A CC 5V/10A 210k 357k 330F 220F V V FB1 FB2 ITH1 ITH2 TRACK/SS1 TRACK/SS2 68.1k 68.1k 0.1F MODE PLLIN/SPREAD 0.1F FREQ GND 7805 TA01a Rev. 0 1 Document Feedback For more information www.analog.comLTC7805 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW Input Supply Voltage (V ) ......................... 0.3V to 40V IN BOOST1, BOOST2 ...................................... 0.3V to 46V Switch Voltage (SW1, SW2) .......................... 5V to 40V RUN1, RUN2 Voltages ................................ 0.3V to 40V 28 27 26 25 24 23 EXTV Voltage ......................................... 0.3V to 30V CC + SENSE1 1 22 SW1 INTV Voltage ............................................ 0.3V to 6V CC SENSE1 2 21 BOOST1 (BOOST1 SW1), (BOOST2 SW2) ............ 0.3V to 6V FREQ 3 20 BG1 + SENSE1 , SENSE1 Voltages ...................... 0.3V to 40V GND MODE 4 19 V IN 29 + RUN1 5 18 EXTV SENSE2 , SENSE2 Voltages ..................... 0.3V to 40V CC RUN2 6 17 INTV CC TRACK/SS1, V Voltages .......................... 0.3V to 6V FB1 SENSE2 7 16 BG2 TRACK/SS2, V Voltages .......................... 0.3V to 6V FB2 + SENSE2 8 15 BOOST2 MODE, PGOOD1, PGOOD2 Voltages ............ 0.3V to 6V 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) UFDM PACKAGE Operating Junction Temperature Range (Notes 2, 8) 28-LEAD (4mm 5mm) PLASTIC QFN LTC7805R, LTC7805J ........................ 40C to 150C T = 150C, = 43C/W JMAX JA EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB Storage Temperature Range .................. 65C to 150C Maximum Junction Temperature (T ) ................... 150C J ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC7805RUFDM PBF LTC7805RUFDM TRPBF 7805 28-Lead (4mm 5mm) Plastic QFN 40C to 150C AUTOMOTIVE PRODUCTS** LTC7805JUFDM WPBF LTC7805JUFDM WTRPBF 7805 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 FB1 FB2 ITH2 ITH1 TRACK/SS2 TRACK/SS1 PLLIN/SPREAD PGOOD2 TG2 PGOOD1 SW2 TG1