. LT3745-1 16-Channel 50mA LED Driver with Buck Controller FEATURES DESCRIPTION n 6V to 55V Power Input Voltage Range The LT 3745-1 integrates a 16-channel LED driver with a n 16 Independent LED Outputs Up to 75mA/36V 55V buck controller. The LED driver lights up to 75mA/36V n 4% LED Current Matching at 50mA (Typ 1%) of LEDs in series per channel, and the buck controller gen- n 6-Bit Dot Correction Current Adjustment erates an adaptive bus voltage supplying the parallel LED n 12-Bit Grayscale PWM Dimming strings. Each channel has individual 6-bit dot correction n 0.5s Minimum LED On-Time current adjustment and 12-bit grayscale PWM dimming. n Adaptive LED Bus Voltage for High Efficiency Both dot correction and grayscale are accessible via a serial n Cascadable 30MHz LVDS Serial Data Interface data interface in LVDS logic. A 4% LED current match- n Full Diagnostic and Protection: Individual Open/Short ing and a 0.5s minimum LED on-time can be achieved LED and Overtemperature Fault at 50mA per channel. n 40-Lead 6mm 6mm QFN Package The LT3745-1 performs full diagnostic and protection against open/short LED and overtemperature fault. The APPLICATIONS fault status is sent back through the serial data interface. n Large Screen Display LED Backlighting The 30MHz fully-buffered, cascadable LVDS serial data n Mono-, Multi-, Full-Color LED Displays interface makes the chip extremely suitable for large screen n LED Billboards and Signboards LCD dynamic backlighting and mono-, multi-, full-color L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and LED displays. The LT3745 uses a TTL/CMOS serial data True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 8058810 interface instead of LVDS. TYPICAL APPLICATION 16-Channel LED Driver, 1MHz Buck, 10 LEDs, 25mA to 75mA per Channel, 500Hz 12-Bit Dimming V IN 42V TO 55V 4.7F 0.47F V CAP IN EN EN/UVLO GATE 47H 25m 100k V CC 47F V CC 267k 3V TO 3.6V 2 10F GND SYNC 10k ISP RT LT3745-1 ISN 46.4k SS FB 10nF LED00 I SET LED01 60.4k T SET LED02 32.4k . LED13 LED14 + 2.048MHz PWMCK LED15 LVDS CLOCK PWMCK + + SCKI SCKO SCKI SCKO LVDS LVDS + + SDI SDO SDI SDO LDI 37451 TA01 37451f 1LT3745-1 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V .......................................................................... 57V IN CAP ......................................................... V 8V to V IN IN 40 39 38 37 36 35 34 33 32 31 GATE ..............................................................CAP to V IN EN/UVLO 1 30 SYNC LED00 to LED15, ISP, ISN .........................................40V LED07 2 29 LED08 ISP .................................................ISN 1V to ISN + 1V LED06 3 28 LED09 FB, RT, T , I ....................................................... 2V LED05 4 27 LED10 SET SET LED04 5 41 26 LED11 V ...............................................................0.3V to 4V CC GND + + + LED03 6 25 LED12 SCKI , SCKI , SCKO , SCKO , SDI , SDI , LED02 + + 7 24 LED13 SDO , SDO , LDI, PWMCK , PWMCK , SYNC, LED01 8 23 LED14 SS, EN/UVLO ............................................. 0.3V to V CC LED00 9 22 LED15 Operating Junction Temperature Range SCKI 10 21 SCKO (Notes 2, 3) 11 12 13 14 15 16 17 18 19 20 LT3745E-1 .........................................40C to 125C LT3745I-1 ..........................................40C to 125C Storage Temperature Range ..................65C to 125C UJ PACKAGE 40-LEAD (6mm 6mm) PLASTIC QFN T = 125C, = 34C/W, = 2.5C/W JMAX JA JC EXPOSED PAD (PIN 41) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3745EUJ-1 PBF LT3745EUJ-1 TRPBF LT3745UJ-1 40-Lead (6mm 6mm) Plastic QFN 40C to 125C LT3745IUJ-1 PBF LT3745IUJ-1 TRPBF LT3745UJ-1 40-Lead (6mm 6mm) 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 nonstandard lead based finish parts. For more information on lead free part marking, go to: