LTC3892/ LTC3892-1/LTC3892-2 60V Low I , Dual, 2-Phase Q Synchronous Step-Down DC/DC Controller FEATURES DESCRIPTION n Wide V Range: 4.5V to 60V (65V Abs Max) The LTC 3892/LTC3892-1/LTC3892-2 is a high perfor- IN n Wide Output Voltage Range: 0.8V V 99% V mance dual step-down DC/DC switching regulator control- OUT IN n Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE) ler that drives all N-channel synchronous power MOSFET n No External Bootstrap Diodes Required stages. Power loss and noise are minimized by operating n Low Operating I : 29A (One Channel On) the two controller output stages out-of-phase. Q n Selectable Gate Drive UVLO Thresholds The gate drive voltage can be programmed from 5V to n Out-of-Phase Operation Reduces Required Input 10V to allow the use of logic or standard-level FETs and Capacitance and Power Supply Induced Noise to maximize efficiency. Internal switches in the top gate n Phase-Lockable Frequency: 75kHz to 850kHz drivers eliminate the need for external bootstrap diodes. n Selectable Continuous, Pulse Skipping or Low Ripple A wide 4.5V to 60V input supply range encompasses a wide Burst Mode Operation at Light Loads n range of intermediate bus voltages and battery chemistries. Selectable Current Limit (LTC3892/LTC3892-2) n Output voltages up to 99% of V can be regulated. OPTI- Very Low Dropout Operation: 99% Duty Cycle IN n LOOP compensation allows the transient response and Power Good Output Voltage Monitors (LTC3892/LTC3892-2) n loop stability to be optimized over a wide range of output Low Shutdown I : 3.6A Q n capacitance and ESR values. Small 32-Lead 5mm 5mm QFN Package (LTC3892/ LTC3892-2) or TSSOP Package (LTC3892-1) The 29A no-load quiescent current extends operating run time in battery powered systems. For a comparison of the LTC3892 to the LTC3892-1 and LTC3892-2, see Table 1 APPLICATIONS in the Pin Functions section of this data sheet. n Automotive and Industrial Power Systems L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are n Distributed DC Power Systems registered trademarks of Analog Devices, Inc. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, n High Voltage Battery Operated Systems 6177787, 6580258. TYPICAL APPLICATION High Efficiency Dual 5V/12V Output Step-Down Converter VIN 12.5V TO 60V RUN1 VIN RUN2 47F Efficiency vs Output Current TG1 TG2 Efciency vs Output Current BOOST1 BOOST2 96 0.1F 0.1F V = 12V IN 5.6H 8m V 5m 15H V OUT1 OUT2 V = 5V 95 OUT 5V 12V SW1 SW2 Burst Mode OPERATION 8A 5A 94 BG1 BG2 220F 150F LTC3892 93 + + 92 SENSE1 SENSE2 100k 1nF 1nF SENSE1 SENSE2 GATE DRIVE 91 V V DRV =5V FB1 FB2 CC 90 DRV =6V CC ITH1 ITH2 DRV =8V CC TRACK/SS1 TRACK/SS2 89 DRV =10V CC 7.15k VPRG1 DRVSET 88 7.5k 34.8k 0.01 0.1 1 10 DRVUV LOAD CURRENT (A) 100pF 0.1F 100pF 0.1F 3892 F01b INTV GND DRV CC CC 2.2nF 1nF 0.1F 4.7F 3892 TA01 38921fc 1 For more information www.linear.com/LTC3892 EFFICIENCY (%)LTC3892/ LTC3892-1/LTC3892-2 ABSOLUTE MAXIMUM RATINGS (Notes 1, 3) TRACK/SS1, TRACK/SS2 Voltages .............. 0.3V to 6V Input Supply Voltage (V ) ......................... 0.3V to 65V IN PGOOD1, PGOOD2 Voltages Top Side Driver Voltages (LTC3892/LTC3892-2) ............................. 0.3V to 6V (BOOST1, BOOST2) ............................... 0.3V to 76V VPRG1, ILIM Voltages Switch Voltage (SW1, SW2) .......................... 5V to 70V (LTC3892/LTC3892-2) ............................. 0.3V to 6V DRV , (BOOST1-SW1), CC Operating Junction Temperature Range (Note 2) (BOOST2-SW2) .......................................0.3V to 11V LTC3892E, LTC3892I, BG1, BG2, TG1, TG2 ........................................... (Note 8) LTC3892E-1, LTC3892I-1, RUN1, RUN2 Voltages ................................ 0.3V to 65V + + LTC3892E-2, LTC3892I-2 ................... 40C to 125C SENSE1 , SENSE2 , SENSE1 LTC3892H, SENSE2 Voltages ................................. 0.3V to 65V LTC3892H-1, LTC3892H-2 ................. 40C to 150C PLLIN/MODE, FREQ Voltages ...................... 0.3V to 6V LTC3892MP, LTC3892MP-1, EXTV Voltage ......................................... 0.3V to 14V CC LTC3892MP-2 .................................... 55C to 150C I , I , V , V Voltages ..................... 0.3V to 6V TH1 TH2 FB1 FB2 Storage Temperature Range .................. 65C to 150C DRVSET, DRVUV Voltages ........................... 0.3V to 6V PIN CONFIGURATION LTC3892/LTC3892-2 LTC3892-1 TOP VIEW TOP VIEW ITH1 1 28 TRACK/SS1 V 2 27 TG1 FB1 + SENSE1 3 26 SW1 32 31 30 29 28 27 26 25 SENSE1 4 25 BOOST1 FREQ 1 24 BOOST1 FREQ 5 24 BG1 PLLIN/MODE 2 23 BG1 PLLIN/MODE 6 23 V IN PGOOD1 3 22 V IN INTV 7 22 EXTV CC PGOOD2 EXTV CC 29 4 21 CC 33 GND GND RUN1 8 21 DRV INTV DRV CC 5 20 CC CC RUN2 9 20 BG2 RUN1 6 19 BG2 RUN2 7 18 BOOST2 SENSE2 10 19 BOOST2 + ILIM 8 17 SW2 SENSE2 11 18 SW2 9 10 11 12 13 14 15 16 V 12 17 TG2 FB2 ITH2 13 16 TRACK/SS2 DRVUV 14 15 DRVSET FE PACKAGE UH PACKAGE 28-LEAD PLASTIC TSSOP 32-LEAD (5mm 5mm) PLASTIC QFN T = 150C, = 30C/W JMAX JA T = 150C, = 44C/W JMAX JA EXPOSED PAD (PIN 29) IS GND, MUST BE CONNECTED TO GND EXPOSED PAD (PIN 33) IS GND, MUST BE CONNECTED TO GND 38921fc 2 For more information www.linear.com/LTC3892 SENSE2 SENSE1 + + SENSE2 SENSE1 V V FB2 FB1 ITH2 ITH1 DRVUV VPRG1 DRVSET TRACK/SS1 TRACK/SS2 TG1 TG2 SW1