POWER LOSS (W) LT3724 High Voltage, Current Mode Switching Regulator Controller FEATURES DESCRIPTION n Wide Input Range: 4V to 60V The LT 3724 is a DC/DC controller used for medium power, n Output Voltages up to 36V (Step-Down) low part count, low cost, high efficiency supplies. It of - n Burst Mode Operation: <100A Supply Current fers a wide 4V-60V input range (7.5V minimum startup n 10A Shutdown Supply Current voltage) and can implement step-down, step-up, inverting n 1.3% Reference Accuracy and SEPIC topologies. n 200kHz Fixed Frequency The LT3724 includes Burst Mode operation, which re- n Drives N-Channel MOSFET duces quiescent current below 100A and maintains n Programmable Soft-Start high efficiency at light loads. An internal high voltage bias n Programmable Undervoltage Lockout regulator allows for simple biasing and can be back driven n Internal High Voltage Regulator for Gate Drive to increase efficiency. n Thermal Shutdown n Additional features include fixed frequency current mode Current Limit Unaffected by Duty Cycle n control for fast line and load transient response a gate driver 16-Pin Thermally Enhanced TSSOP Package capable of driving large N-channel MOSFETs a precision undervoltage lockout function 10A shutdown current APPLICATIONS short-circuit protection and a programmable soft-start function that directly controls output voltage slew rates at n Industrial Power Distribution startup which limits inrush current, minimizes overshoot n 12V and 42V Automotive and Heavy Equipment and facilitates supply sequencing. n High Voltage Single Board Systems n L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Distributed Power Systems Burst Mode is a trademark of Linear Technology Corporation. All other trademarks are the property n Avionics of their respective owners. Protected by U.S. Patents including 5731694, 6498466, 6611131. n Telecom Power TYPICAL APPLICATION High Voltage Step-Down Regulator Efficiency and Power Loss vs Load Current V IN 30V TO 95 12 60V C IN V BOOST IN 68F 90 10 0.22F 1M Si7852 EFFICIENCY TG LT3724 0.025 10 V OUT 85 8 SHDN SW 24V 47H 75W 68.1k SS3H9 + 80 6 C C SS OUT 330F 200k Burst EN V 75 4 CC 1F LOSS V PGND FB 70 2 40.2k V = 48V + IN V SENSE C 65 0 680pF 120pF 1000pF 0.1 1 10 SGND SENSE LOAD CURRENT (A) 4.99k 93.1k 3724 TA01b 3724 TA01a 3724fd 1 EFFICIENCY (%)LT3724 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW Input Supply Voltage (V ) ......................... 65V to 0.3V IN V 1 16 BOOST IN Boosted Supply Voltage (BOOST) .............. 80V to 0.3V NC 2 15 TG Switch Voltage (SW)(Note 8) ........................ 65V to 1V SHDN 3 14 SW Differential Boost Voltage C 4 13 NC SS 17 (BOOST to SW) ...................................... 24V to 0.3V BURST EN 5 12 V CC Bias Supply Voltage (V ) .......................... 24V to 0.3V CC V 6 11 PGND FB + SENSE and SENSE Voltages ................... 40V to 0.3V + V 7 10 SENSE C SGND 8 9 SENSE + (SENSE to SENSE ) ................................... 1V to 1V FE PACKAGE 16-LEAD PLASTIC TSSOP BURST EN Voltage .................................... 24V to 0.3V T = 125C, = 40C/W, = 10C/W JMAX JA JC V , V , C , and SHDN Voltages................. 5V to 0.3V C FB SS EXPOSED PAD IS SGND (PIN 17), MUST BE SOLDERED TO PCB C and SHDN Pin Currents .....................................1mA SS Operating Junction Temperature Range (Notes 2, 3) LT3724E ............................................. 40C to 125C LT3724I .............................................. 40C to 125C LT3724MP.......................................... 55C to 125C Storage Temperature .............................. 65C to 150C Lead Temperature (Soldering, 10 sec) .................. 300C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT3724EFE PBF LT3724EFE TRPBF 3724EFE 16-Lead Plastic TSSOP 40C to 125C LT3724IFE PBF LT3724IFE TRPBF 3724IFE 16-Lead Plastic TSSOP 40C to 125C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3724MPFE LT3724MPFE TR 3724MPFE 16-Lead Plastic TSSOP 55C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: