LTM8040 36V, 1A Module LED Driver and Current Source FEATURES DESCRIPTION n True Color PWM Delivers Constant Color with The LTM 8040 is a xed frequency 1A step-down DC/DC 250:1 Dimming Ratio Module regulator designed to operate as a constant cur- n Wide Input Range: 4V to 36V rent source. Internal circuitry monitors the output current n Up to 1A LED Current to provide accurate current regulation, which is ideal for n Adjustable Control of LED Current driving high current LEDs. High output current accuracy n High Output Current Accuracy is Maintained Over a is maintained over a wide current range, from 35mA to Wide Range from 35mA to 1A 1A, allowing a wide dimming range over an output volt- n Open LED and Short-Circuit Protection age range of 2.5V to 13V. Unique PWM circuitry allows a n Grounded LED Cathode Connection dimming range of 250:1, avoiding the color shift normally n Small Footprint (15mm 9mm 4.32mm) associated with LED current dimming. Surface Mount LGA Package With its wide input range of 4V to 36V, the LTM8040 regu- lates a broad array of power sources, from 4-cell batteries APPLICATIONS and 5V logic rails to unregulated wall transformers, lead n Automotive and Avionic Lighting acid batteries and distributed power supplies. n Architectural Detail Lighting The LTM8040 is packaged in a thermally enhanced, n Display Backlighting compact (15mm 9mm 4.32mm) molded land grid n Constant Current Sources array (LGA) package suitable for automated assembly L, LT, LTC, LTM, Module, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. True Color PWM is a trademark of Linear Technology by standard surface mount equipment. The LTM8040 is Corporation. All other trademarks are the property of their respective owners. Pb-free and RoHS compliant. TYPICAL APPLICATION 1A Module LED Driver Ef ciency V * IN 100 V LEDA IN 11.5V TO 36V SHDN LPWR 90 1F LTM8040 80 TWO WHITE LEDs 6V TO 9V 70 ADJ BIAS 1A PWM 60 RT 50 GND 215k 650kHz 40 30 8040 TA01 V = 12V IN 20 TWO 3.3V AT 1A LEDs *RUNNING VOLTAGE. SEE APPLICATION INFORMATION OUTPUT CURRENT ADJUSTED 10 FOR START-UP REQUIREMENTS WITH ADJ VOLTAGE 0 0 200 400 600 800 1000 OUTPUT CURRENT (mA) 8040 TA01b 8040fa 1 EFFICIENCY (%)LTM8040 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) V ............................................................................36V IN PWM BIAS .......................................................................... 25V LEDA BIAS + V ................................................................. 51V BANK 1 IN BIAS LEDA, LPWR .............................................................15V SHDN PWM .........................................................................10V ADJ GND ADJ .............................................................................6V RT BANK 2 RT ...............................................................................3V GND SHDN ........................................................................36V V LPWR IN SHDN Above V .........................................................6V BANK 3 IN T = 125C, = 13C/W, = 4.4C/W, WEIGHT = 1.73g Internal Operating Temperature (Note 2) ...40C to 125C JMAX JA JC 66 LEAD (15mm 9mm 4.32mm) Max Solder Temperature ....................................... 245C DERIVED FROM 6.35cm 6.35cm 4 LAYER PCB JA ORDER INFORMATION LEAD FREE FINISH TRAY PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE (NOTE 3) LTM8040EV PBF LTM8040EV PBF LTM8040V 0C to 125C 66-Lead 15mm 9mm 4.32mm LGA Package LTM8040IV PBF LTM8040IV PBF LTM8040V 40C to 125C 66-Lead 15mm 9mm 4.32mm LGA Package 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: