LT3597 60V Triple Step-Down LED Driver Fea T Descrip T n Three 100mA Buck Regulators, Each Drives Up to The LT 3597 is a 60V triple step-down LED driver capable 10 LEDs with Fast NPN Current Sources of achieving 10,000:1 digital PWM dimming at 100Hz with n Fast Current Sources for <1s Pulse Widths fast NPN current sources driving up to 10 LEDs in each (10,000:1 True Color PWM Dimming at 100Hz) channel. LED dimming can also be achieved via analog n LEDs Disconnected in Shutdown control of the CTRL1-3 pin. n Adaptive V for Increased Efficiency OUT The step-down switching frequency is programmed be- n 6V to 60V Input Voltage Range tween 200kHz and 1MHz. The frequency is also synchroniz- n 2% LED Current Matching able to an external clock. The LT3597 provides maximum n External Resistor Sets LED Current for Each Channel LED brightness while adhering to manufacturers speci- n Internal Compensation and Soft-Start fications for thermal derating. The derate temperature is n Programmable Switching Frequency (200kHz to 1MHz) programmed by placing a negative temperature coefcfi ient n Synchronizable to External Clock (NTC) resistor on the master control pin. n Open LED Detection and Reporting n The LT3597 adaptively controls V in order to achieve Shorted LED Pin Protection and Reporting OUT n optimal efficiency. Other features include: 2% LED cur - Programmable LED Thermal Derating n rent matching between channels, open LED reporting, Programmable Temperature Protection n shorted LED protection, programmable LED current, and 5mm 8mm Thermally Enhanced QFN Package programmable temperature protection. with a 0.6mm High Voltage Pin Spacing L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of a T their respective owners. n LED Billboards and Signboards n Mono, Multi, Full-Color LED Displays n Large Screen Display LED Backlighting n Automotive, Industrial, and Medical Displays Typical a T Triple Step-Down RGB Single Pixel LED Driver, 100mA Current V IN V BOOST2 48V IN 10F 270k 10,000:1 PWM Dimming at 100Hz 0.1F 100H V OUT2 EN/UVLO SW2 91k 3.3F 97k BOOST1 DA2 V OUT1 100H 0.1F 9.1k G SW1 FB2 97k 3.3F PWM 2V/DIV DA1 V OUT2 R LED2 9.1k FB1 BOOST3 LLT3597T3597 0.1F 100H V OUT3 V SW3 OUT1 I LED LED1 50mA/DIV 3.3F 97k V CC BIAS DA3 5V 10F 9.1k 100k B FB3 3597 TA01b 200ns/DIV FAULT 3 PWM1-3 V OUT3 3 CTRL1-3 LED3 SYNC V V REF REF RT 10k 82.5k T SET 33.2k CTRLM I I I GND SET1 SET2 SET3 49.9k 3597 TA01a 100k (1MHz) 20k 20k 20k 3597fa 1 ion pplica ions pplica ion uresLT3597 a Te Maxi Mu M r a T p in c F T (Note 1) TOP VIEW Input Voltage (V ), EN/UVLO ...................................60V IN BOOST1-3 .................................................................85V BOOST Pin Above SW Pin ........................................ 25V 51 50 48 46 44 LED1-3, V ........................................................42V OUT1-3 43 DA3 BIAS, FAULT ..............................................................25V BST1 2 V , RT, I , T , CTRLM ...................................3V REF SET1-3 SET 41 SW3 FB1-3, CTRL1-3, PWM1-3, SYNC ...............................6V SW1 4 Operating Junction Temperature Range 39 BST3 DA1 6 (Notes 2, 3) ........................................40C to 125C FB1 7 37 BIAS Maximum Junction Temperature........................... 125C Storage Temperature Range ...................65C to 150C 53 EN/UVLO 9 35 FB3 GND 34 FB2 T 11 33 CTRL1 SET V 12 32 CTRL2 REF CTRLM 13 31 CTRL3 I 14 30 PWM1 SET1 I 15 29 PWM2 SET2 I 16 28 PWM3 SET3 RT 17 27 SYNC 18 19 20 21 22 23 24 25 26 UHG PACKAGE VARIATION: UHG52(39) 52-LEAD (5mm 8mm) PLASTIC QFN T = 125C, = 32C/W JMAX JA EXPOSED PAD (PIN 53) IS GND, MUST BE SOLDERED TO PCB Der in F Ma T LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3597EUHG PBF LT3597EUHG TRPBF 3597 52-Lead (5mm 8mm) Plastic QFN 40C to 125C LT3597IUHG PBF LT3597IUHG TRPBF 3597 52-Lead (5mm 8mm) Plastic QFN 40C to 125C 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: