EVALUATION KIT AVAILABLEEVALUATION KIT AVAILABLE Programmable, Four-String HB MAX16826 LED Driver with Output-Voltage Optimization and Fault Detection General Description Benefits and Features The MAX16826 high-brightness LED (HB LED) driver is 4 Channels of Programmable, Fault-Protected, Con- designed for backlighting automotive LCD displays and stant-Current Source-Driver Controllers for All White, other display applications such as industrial or desktop RGB, or RGB Plus Amber LED Configurations monitors and LCD televisions. The MAX16826 integrates Drives One to Four LED Strings a switching regulator controller, a 4-channel linear cur- Individual PWM Dimming Inputs per String rent sink driver, an analog-to-digital converter (ADC), Very Wide Dimming Range 2 and an I C interface. The IC is designed to withstand Configurable as a boost or SEPIC Converter with automotive load dump transients up to 40V and can Programmable 100kHz to 1MHz Switching Frequency operate under cold crank conditions. for Design Flexibility The MAX16826 contains a current-mode PWM switching Integrated Boost/SEPIC Controller regulator controller that regulates the output voltage to External MOSFETs Allow Wide-Range LED the LED array. The switching regulator section is config- Current with Multiple LEDs per String urable as a boost or SEPIC converter and its switching 200kHz to 2MHz Programmable Switching frequency is programmable from 100kHz to 1MHz. Frequency for Optimizing Size vs. Efficiency The MAX16826 includes 4 channels of programmable, External Switching-Frequency Synchronization fault-protected, constant-current sink driver controllers 2 I C Allows the Current-Sink Drain Voltages to be that are able to drive all white, RGB, or RGB plus amber Read to Minimize Power Dissipation and Detect LED LED configurations. LED dimming control for each chan- String Fault Conditions nel is implemented by direct PWM signals for each of the 7-Bit Internal ADC for LED Voltage Monitoring and four linear current sinks. An internal ADC measures the Optimization drain voltage of the external driver transistors and the Dynamic Adjustment of LED String Currents and output of the switching regulator. These measurements 2 Output Voltage are then made available through the I C interface to an external microcontroller (C) to enable output voltage Standby Mode optimization and fault monitoring of the LEDs. Protection Features Improve Reliability LED Short and Open Detection The amplitude of the LED current in each linear current- sink channel and the switch-mode regulator output volt- Overvoltage and Overtemperature Protection 2 age is programmed using the I C interface. Additional Ordering Information appears at end of data sheet. features include: cycle-by-cycle current limit, shorted LED string protection, and overtemperature protection. Simplified Diagram The MAX16826 is available in a thermally enhanced, 5mm x 5mm, 32-pin thin QFN package and is specified over the automotive -40C to +125C temperature range. VIN Applications LCD Backlighting: Automotive Infotainment Displays Automotive Cluster Displays Industrial and Desktop Monitors IN DL CS FB DIM1 DR4 LCD TVs DIM2 DIMMING DIM3 INPUTS DR1 Automotive Lighting: DIM4 DL1 Adaptive Front Lighting MAX16826 CS1 Low- and High-Beam Assemblies 2 SDA I C INTERFACE SCL DL4 CS4 Typical Application Circuit and Pin Configuration appear at GND end of data sheet. BOOST LED DRIVER 19-4047 Rev 8 7/21Programmable, Four-String HB MAX16826 LED Driver with Output-Voltage Optimization and Fault Detection Absolute Maximum Ratings IN to GND (Continuous) .........................................-0.3V to +30V All Other Pins Current.......................................................20mA IN Peak Current ( 400ms) ...............................................300mA Continuous Power Dissipation (T = +70C) A IN Continuous Current ........................................................50mA 32-Pin Thin QFN (derate 34.5mW/C above +70C) PGND to GND .......................................................-0.3V to +0.3V Multilayer Board ..........................................................2759mW All Other Pins to GND...............................................-0.3V to +6V Operating Temperature Range .........................-40C to +125C DL Peak Current (< 100ns)....................................................3A Junction Temperature......................................................+150C DL Continuous Current.....................................................50mA Storage Temperature Range .............................-65C to +150C DL1, DL2, DL3, DL4 Peak Current ..................................50mA Lead Temperature (soldering, 10s)........+300C DL1, DL2, DL3, DL4 Continuous Current ........................20mA Soldering Temperature (reflow) .......................................+260C V Continuous Current .....................................................50mA CC Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Electrical Characteristics (V = 12V, R19 = 2k, C33 = 2200pF, R17 = 1.27k, C = 0.01F, T = -40C to +125C, unless otherwise noted. Typical values IN DL J are at T = +25C.) (Note 1) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Power-Supply Voltage V V = 3V 4.75 24 V IN SYNC Quiescent Current I DL = unconnected R19, C33 = open 5 10 mA IN Shutdown Current I V = 0V 20 75 A IN,SD SYNC 2 Standby Current I I C standby activated 3 mA IN,SB 2 I C-COMPATIBLE I/O (SCL, SDA) Input High Voltage V 1.5 V IH Input Low Voltage V 0.5 V IL Input Hysteresis V 25 mV HYS Input High Leakage Current I V = 5V -1 +1 A IH LOGIC Input Low Leakage Current I V = 0V -1 +1 A IL LOGIC Input Capacitance C 10 pF IN Output Low Voltage V I = 3mA 0.4 V OL OL Output High Current I V = 5V 1 A OH OH 2 I C-COMPATIBLE TIMING Serial Clock (SCL) Frequency f 400 kHz SCL BUS Free Time Between STOP t 1.3 s BUF and START Conditions START Condition Hold Time t 0.6 s HD:STA STOP Condition Setup Time t 0.6 s SU:STO Clock Low Period t 1.3 s LOW Clock High Period t 0.6 s HIGH Data Setup Time t 0.3 s SU:DAT Data In Hold Time t 0.03 0.9 s HD:DATIN Data Out Hold Time t 0.3 s HD:DATOUT www.maximintegrated.com Maxim Integrated 2