POWER LOSS (mW) LTC3890-1 60V Low I , Dual, 2-Phase Q Synchronous Step-Down DC/DC Controller FEATURES DESCRIPTION n Wide V Range: 4V to 60V (65V Abs Max) The LTC 3890-1 is a high performance dual step-down IN n switching regulator DC/DC controller that drives all Low Operating I : 50A (One Channel On) Q n N-channel synchronous power MOSFET stages. A constant Wide Output Voltage Range: 0.8V V 24V OUT n frequency current mode architecture allows a phase- R or DCR Current Sensing SENSE n lockable frequency of up to 850kHz. Power loss and supply Out-of-Phase Controllers Reduce Required Input noise are minimized by operating the two controller output Capacitance and Power Supply Induced Noise n stages out-of-phase. Phase-Lockable Frequency (75kHz to 850kHz) n Programmable Fixed Frequency (50kHz to 900kHz) The 50A no-load quiescent current extends operating life n Selectable Continuous, Pulse-Skipping or Low Ripple in battery-powered systems. OPTI-LOOP compensation Burst Mode Operation at Light Loads allows the transient response to be optimized over a wide n Very Low Dropout Operation: 99% Duty Cycle range of output capacitance and ESR values. A wide 4V n Adjustable Output Voltage Soft-Start or Tracking to 60V input supply range encompasses a wide range of n Power Good Output Voltage Monitor intermediate bus voltages and battery chemistries. n Output Overvoltage Protection Independent TRACK/SS pins for each controller ramp the n Low Shutdown I : <14A Q output voltages during start-up. Current foldback limits n Internal LDO Powers Gate Drive from V or EXTV IN CC MOSFET heat dissipation during short-circuit conditions. n No Current Foldback During Start-Up The PLLIN/MODE pin selects among Burst Mode operation, n Narrow SSOP Package pulse-skipping mode, or continuous conduction mode at light loads. APPLICATIONS For a leadless 32-pin QFN package with additional features n Automotive Always-On Systems of adjustable current limit, clock out, phase modulation n Battery Operated Digital Devices and two PGOOD outputs, see the LTC3890 data sheet. n Distributed DC Power Systems L, LT, LTC, LTM, Linear Technology, Burst Mode, OPTI-LOOP and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6100678, 6144194, 6177787, 6304066, 6580258, 7230497. TYPICAL APPLICATION High Efficiency Dual 8.5V/3.3V Output Step-Down Converter Efficiency and Power Loss V vs Output Current IN 9V TO 60V 22F 10000 100 4.7F V = 12V IN V INTV IN CC 90 V = 3.3V OUT TG1 TG2 1000 80 0.1F 0.1F BOOST1 BOOST2 4.7H 8H 70 SW1 SW2 100 60 BG1 BG2 50 LTC3890-1 PGND 10 40 + + SENSE1 SENSE2 30 0.01 0.008 20 1 V SENSE2 OUT2 10 V SENSE1 OUT1 8.5V 3.3V V V FB1 FB2 0 0.1 3A 5A 100k 100k ITH1 ITH2 0.0001 0.001 0.01 0.1 1 10 470F 1000pF 1000pF 330F OUTPUT CURRENT (A) TRACK/SS1 TRACK/SS2 SGND 10.5k 38901 TA01b 31.6k 34.8k 34.8k 0.1F 0.1F 38901 TA01a 38901fb 1 EFFICIENCY (%)LTC3890-1 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW Input Supply Voltage (V ) ......................... 0.3V to 65V IN Topside Driver Voltages ITH1 1 28 TRACK/SS1 BOOST1, BOOST2 ..................................0.3V to 71V V 2 27 PGOOD1 FB1 + SENSE1 3 26 TG1 Switch Voltage (SW1, SW2) ......................... 5V to 65V SENSE1 4 25 SW1 (BOOST1-SW1), (BOOST2-SW2) ................ 0.3V to 6V FREQ 5 24 BOOST1 RUN1, RUN2 ............................................... 0.3V to 8V PLLIN/MODE 6 23 BG1 Maximum Current Sourced into Pin SGND 7 22 V IN from Source >8V ...................................................100A RUN1 8 21 PGND + + SENSE1 , SENSE2 , SENSE1 RUN2 9 20 EXTV CC SENSE2 Voltages ..................................... 0.3V to 28V SENSE2 10 19 INTV CC PLLIN/MODE, INTV Voltages ................... 0.3V to 6V CC + SENSE2 11 18 BG2 FREQ Voltage ........................................0.3V to INTV CC V 12 17 BOOST2 FB2 EXTV ..................................................... 0.3V to 14V CC ITH2 13 16 SW2 ITH1, ITH2, V , V Voltages ................... 0.3V to 6V FB1 FB2 TRACK/SS2 14 15 TG2 PGOOD1 Voltage ......................................... 0.3V to 6V GN PACKAGE 28-LEAD PLASTIC SSOP TRACK/SS1, TRACK/SS2 Voltages ............. 0.3V to 6V T = 150C, = 90C/W JMAX JA Operating Junction Temperature Range (Notes 2, 3) LTC3890E-1, LTC3890I-1 ................... 40C to 125C LTC3890H-1 ....................................... 40C to 150C LTC3890MP-1 .................................... 55C to 150C Storage Temperature Range .................. 65C to 150C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3890EGN-1 PBF LTC3890EGN-1 TRPBF LTC3890GN-1 28-Lead Plastic SSOP 40C to 125C LTC3890IGN-1 PBF LTC3890IGN-1 TRPBF LTC3890GN-1 28-Lead Plastic SSOP 40C to 125C LTC3890HGN-1 PBF LTC3890HGN-1 TRPBF LTC3890GN-1 28-Lead Plastic SSOP 40C to 150C LTC3890MPGN-1 PBF LTC3890MPGN-1 TRPBF LTC3890GN-1 28-Lead Plastic SSOP 55C to 150C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: