XXRRPP77661188 88--CChhaannnneell CCoonnssttaanntt CCuurrrreenntt LLiinneeaarr LLEEDD DDrriivveerr WWiitthh TTMM Smart Talk Smart Talk February 2013 Rev. 1.2.0 GENERAL DESCRIPTION APPLICATIONS The XRP7618 is an 8-channel, high voltage, LCD Backlighting constant-current sink LED driver capable of Desktop, Notebook and TV Displays driving up to 100mA current per channel. With outputs rated at 30V, the XRP7618 can control Industrial and Medical Displays strings of multiple LEDs with better than Signage Backlighting 1.5% channel to channel current matching. LED channel current is programmed via an FEATURES external resistor within a 10mA to 100mA range. Dimming control is supported through a 8 Constant-Current Channels standard PWM scheme up to 25kHz or through Adjustable up to 100mA per Channel an analog signal. Channel Paralleling for higher Current TM Featuring Exars Smart Talk technology, 1.5% Current Matching Accuracy when combined with a boost converter, the Up to 30V LED Channel Voltage Range XRP7618 maximizes the overall system efficiency by dynamically reporting the 5V Biasing Voltage and Control minimum LED voltage necessary to maintain TM Smart Talk Power Optimization current regulation mode. Multiple channels can be combined to increase current driving Parallel Operations Support capability per channel and multiple XRP7618s PWM and Analog Dimming can be placed in parallel to drive over 8 strings of LEDs. UVLO, Open LED & Over Temperature protection An under voltage lock out, open LED and over temperature protections insure safe operations RoHS Compliant Halogen Free, under abnormal operating conditions. 20-pin TSSOP (EP) Package The XRP7618 is available in RoHS compliant, green/halogen free space saving 20-pin TSSOP (EP) package. TYPICAL APPLICATION DIAGRAM Fig. 1: XRP7618 Typical Application Diagram Exar Corporation www.exar.com 48720 Kato Road, Fremont CA 94538, USA Tel. +1 510 668-7000 Fax. +1 510 668-7001 XXRRPP77661188 88--CChhaannnneell CCoonnssttaanntt CCuurrrreenntt LLiinneeaarr LLEEDD DDrriivveerr WWiitthh TTMM Smart Talk Smart Talk ABSOLUTE MAXIMUM RATINGS OPERATING RATINGS These are stress ratings only and functional operation of Input Voltage Range V .............................. 4.2V to 5.5V CC the device at these ratings or any other above those PWM Dimming Frequency .......................0.1KHz to 25KHz indicated in the operation sections of the specifications Current per Channel ..................................................... below is not implied. Exposure to absolute maximum V 0.5V ........................................... 10mA to 25mA CHx rating conditions for extended periods of time may affect V 1V .............................................. 10mA to 65mA CHx reliability. V 1.5V ..........................................10mA to 110mA CHx V , ISET, EN, FB, SDB, PWM ...................... -0.3V to 6.0V CC Operating Temperature Range ................... -40C to 85C CHx .......................................................... -0.3V to 30V 1 Thermal Resistance (TSSOP-20) .................... 35C/W JA Junction Temperature .......................................... 150C 2 Note 1: The device is soldered to a 60mm plane of Storage Temperature .............................. -65C to 150C copper (4mm 15mm - top side solder mask) of 1oz. on a Power Dissipation ................................ Internally Limited PCB with 80.5mm vias. Lead Temperature (Soldering, 10 sec) ................... 260C ESD Rating (HBM - Human Body Model) .................... 6kV ESD Rating (MM - Machine Model) ........................... 200V ELECTRICAL SPECIFICATIONS Specifications with standard type are for an Operating Junction Temperature of T = 25C only. Minimum and Maximum J limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at T = 25C, and are provided for reference purposes only. Unless otherwise indicated, V = 5V, R = 8.2k, T = J CC ISET A 25C. Parameter Min. Typ. Max. Units Conditions V Operating Input Voltage Range V 4.2 5.0 5.5 CC Shutdown Supply Current 0.1 1 A V =0V EN Quiescent Supply Current 0.5 1 mA No load V Under Voltage Lockout threshold 3.6 3.8 4.0 Falling edge mV Under Voltage Lockout Hysteresis 200 ISET Reference Voltage 1.194 1.218 V 1.170 Current Multiplication Ratio 400 430 I /I 370 CHX SET 23 45 VCHX=0.5V mA Maximum Output Current per Channel 65 70 V =1.0V CHX 110 120 V =1.5V CHX Any 2 channels LED Current Matching 1.5 % -1.5 V =1.0V, I =60mA CHX CHX 0.45 I =20mA CHX Current Sink Saturation Voltage 0.8 V I =60mA CHX 1.2 I =100mA CHX %/V Output Current Line Regulation 2 V =4.2V to 5.5V CC Output Current Load Regulation 4 % V =0.5V to 2.8V CHX Enable Logic LOW 0.8 V XRP7618 is disabled Enable Logic HIGH V XRP7618 is active 1.8 V PWM Pin Logic LOW 0.8 XRP7618 is disabled V PWM Pin Logic HIGH 1.8 XRP7618 is active SDB Pin Logic LOW 0.4 V SDB Pin Logic HIGH V 2.4 A Feedback Output Current 5 15 C Thermal Shutdown Die Temperature 160 Thermal Shutdown Hysteresis 20 C 2013 Exar Corporation 2/10 Rev. 1.2.0