POWER LOSS (mW) LTC3834 30A I Synchronous Q Step-Down Controller FEATURES DESCRIPTION n Wide Output Voltage Range: 0.8V V 10V The LTC 3834 is a high performance step-down switching OUT n Low Operating Quiescent Current: 30A regulator controller that drives an all N-channel synchro- n OPTI-LOOP Compensation Minimizes C nous power MOSFET stage. A constant-frequency current OUT n 1% Output Voltage Accuracy mode architecture allows a phase-lockable frequency of n Wide V Range: 4V to 36V up to 650kHz. IN n Phase-Lockable Fixed Frequency 140kHz to 650kHz The 30A no-load quiescent current extends operating n Dual N-Channel MOSFET Synchronous Drive life in battery powered systems. OPTI-LOOP compensa- n Very Low Dropout Operation: 99% Duty Cycle tion allows the transient response to be optimized over n Adjustable Output Voltage Soft-Start or Tracking a wide range of output capacitance and ESR values. The n Output Current Foldback Limiting LTC3834 features a precision 0.8V reference and a power n Power Good Output Voltage Monitor good output indicator. The 4V to 36V input supply range n Clock Output for PolyPhase Applications encompasses a wide range of battery chemistries. n Output Overvoltage Protection n The TRACK/SS pin ramps the output voltage during Low Shutdown I : 4A Q n start-up. Current foldback limits MOSFET heat dissipa- Internal LDO Powers Gate Drive from V or V IN OUT n tion during short-circuit conditions. A reduced feature set Selectable Continuous, Pulse Skipping or version of the part (LTC3834-1) is available in a smaller, Burst Mode Operation at Light Loads n lower pin count package. Small 20-Lead TSSOP or 4mm 5mm QFN Package Comparison of LTC3834 and LTC3834-1 CLKOUT/ APPLICATIONS PART PHASMD EXTV PGOOD PACKAGES CC LTC3834 Yes Yes Yes FE20/4mm 5mm QFN n Automotive Systems LTC3834-1 No No No GN16/3mm 5mm DFN n Telecom Systems L, LT, LTC, LTM, Burst Mode, PolyPhase and OPTI-LOOP are registered trademarks of Linear n Battery-Operated Digital Devices Technology Corporation. All other trademarks are the property of their respective owners. n Protected by U.S. Patents, including 5408150, 5481178, 5705919, 5929620, 6304066, Distributed DC Power Systems 6498466, 6580258, 6611131. TYPICAL APPLICATION High Ef ciency Synchronous Step-Down Converter V IN CLKOUT V IN 4V TO 36V 10000 100 PLLLPF 10F TG RUN 90 0.01F 0.22F PGOOD 1000 80 TRACK/SS BOOST 70 3.3H V 0.012 OUT I TH SW 3.3V 100 560pF 60 LTC3834 5A 150pF 50 150F 54.2k 40 10 SGND INTV CC 30 4.7F 68.1k PLLIN/MODE EXTV CC 20 1 V BG FB 10 SENSE 0 0.1 215k 0.000001 0.0001 0.01 1 + SENSE PGND OUTPUT CURRENT (A) 3834 TA01b 3834 TA01 3834fb 1 EFFICIENCY (%)LTC3834 ABSOLUTE MAXIMUM RATINGS (Note 1) Input Supply Voltage (V ) ......................... 36V to 0.3V I , V Voltages ...................................... 2.7V to 0.3V IN TH FB Topside Driver Voltage (BOOST) ................ 42V to 0.3V Peak Output Current <10s (TG, BG) ..........................3A Switch Voltage (SW) ..................................... 36V to 5V INTV Peak Output Current ................................. 50mA CC INTV , (BOOST-SW), CLKOUT, PGOOD .. 8.5V to 0.3V Operating Temperature Range (Note 2).... 40C to 85C CC RUN, TRACK/SS ......................................... 7V to 0.3V Junction Temperature (Note 3) ............................. 125C + SENSE , SENSE Voltages ........................ 11V to 0.3V Storage Temperature Range ................... 65C to 150C PLLIN/MODE, PHASMD, PLLLPF ......... INTV to 0.3V Lead Temperature (Soldering, 10 sec) CC EXTV ...................................................... 10V to 0.3V FE Package .......................................................300C CC PIN CONFIGURATION TOP VIEW TOP VIEW CLKOUT 1 PHASMD 20 PLLLPF 2 PLLIN/MODE 19 20 19 18 17 I 3 PGOOD 18 TH + I 1 16 PGOOD TH TRACKS/SS 4 SENSE 17 + TRACK/SS 2 15 SENSE V 5 21 SENSE 16 FB V 3 14 SENSE FB SGND 6 RUN 15 21 SGND 4 13 RUN PGND 7 BOOST 14 PGND 5 12 BOOST BG 8 TG 13 BG 6 11 TG INTV 9 12 SW CC 7 8 9 10 EXTV 10 11 V CC IN FE PACKAGE 20-LEAD PLASTIC TSSOP UFD PACKAGE T = 125C, = 35C/W JMAX JA 20-PIN (4mm s 5mm) PLASTIC QFN EXPOSED PAD (PIN 21) IS SGND, MUST BE SOLDERED TO PCB T = 125C, = 37C/W JMAX JA EXPOSED PAD (PIN 21) IS SGND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3834EFE PBF LTC3834EFE TRPBF LTC3834FE 20-Lead Plastic TSSOP 40C to 85C (Note 2) LTC3834IFE PBF LTC3834IFE TRPBF LTC3834FE 20-Lead Plastic TSSOP 40C to 85C LTC3834EUFD PBF LTC3834EUFD TRPBF 3834 40C to 85C (Note 2) 20-Lead (4mm 5mm) Plastic QFN LTC3834IUFD PBF LTC3834IUFD TRPBF 3834 40C to 85C 20-Lead (4mm 5mm) Plastic QFN Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: