LT7101 105V, 1A Low EMI Synchronous Step-Down Regulator with Fast Current Programming FEATURES DESCRIPTION n Wide V Range: 4.4V to 105V (110V Abs Max) The LT 7101 is a high efficiency, monolithic synchro- IN n Ultralow EMI/EMC Emissions: CISPR 25 Compliant nous step-down DC/DC converter utilizing a constant n 2A I When Regulating 48V to 3.3V frequency, average current mode control architecture. It Q IN OUT n Fast and Accurate Output Current Programming and operates from an input voltage range of 4.4V to 105V and Monitoring with No External R provides an adjustable regulated output voltage from 1V SENSE n Brick Wall Current Limit to V while delivering up to 1A of output current. IN n Low Minimum On-Time: 35ns The LT7101 features high frequency operation and a low n Wide V Range: 1V to V OUT IN minimum on-time that reduce inductor size and enable n 100% Maximum Duty Cycle Operation constant-frequency operation even at very high step- n Programmable Fixed Frequency: 200kHz to 2MHz down ratios. In addition, the LT7101 achieves the lowest n Eight, Pin-Selectable Fixed (1.2V to 15V) or possible dropout voltage with 100% maximum duty cycle Adjustable Output Voltages operation. During light load operation, converter efficiency n Selectable Continuous, Pulse-Skipping, or Low and output ripple can be optimized by selecting Burst Ripple Burst Mode Operation at Light Loads Mode, pulse-skipping or forced continuous operation. n PLL Synchronization to External Clock n The LT7101 includes accurate, high speed average cur- EXTV LDO Powers Chip from V = 3.3V to 40V CC OUT n rent programming and monitoring without the need for OPTI-LOOP or Fixed Internal Compensation n an external sense resistor. Additional features include a Input and Output Overvoltage Protection n bypass LDO to maximize efficiency, fixed or adjustable Thermally Enhanced (5mm 6mm) QFN Package output voltage and loop compensation, and a wide array of protection features to enhance reliability. APPLICATIONS All registered trademarks and trademarks are the property of their respective owners. n Battery Chargers and CC/CV Supplies n Automotive and Military Systems n Industrial, Avionics and Heavy Equipment n Medical Instruments and Telecommunication Systems TYPICAL APPLICATION Efficiency vs Load Current 5V to 105V Input to 5V/1A Output Step-Down Regulator 100 f = 300kHz SW 95 FIGURE 14 CIRCUIT V IN 90 V BOOST IN 5V TO 105V 0.1F 85 4.7F 47H V LT7101 OUT 5V RUN SW 80 1A I V CTRL FB 75 OVLO EXTV 47F CC 70 CURRENT V I MON PRG2 MONITOR 65 PLLIN/MODE I V = 12V TH IN 60 V = 24V IN FREQ INTV CC V = 48V IN 55 V = 72V SGND PGND IN 1F 50 0.1 1 10 100 1000 7101 TA01a LOAD CURRENT (mA) 7101 TA01b Rev. 0 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LT7101 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V Supply Voltage ....................................0.3V to 110V IN INTV , (BOOST-SW) Voltages .................... 0.3V to 6V CC BOOST Voltage .........................................0.3V to 110V 36 35 32 31 30 RUN Voltage..............................................0.3V to 110V BOOST V , PGOOD Voltages ................................ 0.3V to 16V 27 FB RUN 3 26 SW EXTV Voltage ..........................................0.3V to 41V CC 25 SW R , V , V Voltages .................0.3V to INTV IND PRG1 PRG2 CC 24 SW PGND I , SS Voltages ................................0.3V to INTV CTRL CC 37 SGND 6 FREQ, I , PLLIN/MODE, OVLO Voltages..... 0.3V to 6V TH OVLO 7 Operating Junction Temperature Range (Notes 2, 3, 4) R 8 21 INTV IND CC LT7101E, LT7101I............................... 40C to 125C I 9 20 EXTV TH CC V 10 19 V LT7101H............................................. 40C to 150C FB PRG2 11 12 13 14 15 16 17 18 LT7101MP .......................................... 55C to 150C Storage Temperature Range .................. 65C to 150C UHE36(26) PACKAGE 36-LEAD (5mm 6mm) PLASTIC QFN T = 150C, = 38C/W, = 5C/W JMAX JA JC EXPOSED PAD (PIN 37) IS PGND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT7101EUHE PBF LT7101EUHE TRPBF 7101 36-Lead (5mm 6mm) Plastic QFN 40C to 125C LT7101IUHE PBF LT7101IUHE TRPBF 7101 36-Lead (5mm 6mm) Plastic QFN 40C to 125C LT7101HUHE PBF LT7101HUHE TRPBF 7101 36-Lead (5mm 6mm) Plastic QFN 40C to 150C LT7101MPUHE PBF LT7101MPUHE TRPBF 7101 36-Lead (5mm 6mm) Plastic QFN 55C 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. Rev. 0 2 For more information www.analog.com FREQ PGND PLLIN/MODE PGND CLKOUT PGOOD SS V IN I V CTRL IN I V MON IN V PRG1