EVALUATION KIT AVAILABLE MAX16812 Integrated High-Voltage LED Driver with Analog and PWM Dimming Control General Description Features The MAX16812 is a peak-current-mode LED driver with Integrated 76V, 0.2 (typ) Power MOSFET an integrated 0.2 power MOSFET designed to control 5.5V to 76V Wide Input Range the current in a single string of high-brightness LEDs Adjustable LED Current with 5% Accuracy (HB LEDs). The MAX16812 can be used in multiple Floating Differential LED Current-Sense Amplifier converter topologies such as buck, boost, or buck-boost. The MAX16812 operates over a 5.5V to 76V wide supply Floating Dimming N-Channel MOSFET Driver voltage range. PWM LED Dimming with: The MAX16812 features a low-frequency, wide-range PWM Control Signal Analog Control Signal brightness adjustment (100:1), analog and PWM dim- Chopped V Input ming control input, as well as a resistor-programmable IN EMI suppression circuitry to control the rise and fall times Peak-Current-Mode Control of the internal switching MOSFET. A high-side LED cur- 125kHz to 500kHz Adjustable Switching Frequency rent-sense amplifier and a dimming MOSFET driver are Adjustable UVLO and Soft-Start also included, simplifying the design and reducing the Output Overvoltage Protection total component count. 5s LED Current Rise/Fall Times During Dimming The MAX16812 uses peak-current-mode control, adjust- Minimize EMI able slope compensation that allows for additional design flexibility. The device has two current regulation loops. Overtemperature and Short-Circuit Protection The first loop controls the internal switching MOSFET Ordering Information peak current, while the second current regulation loop controls the LED current. Switching frequency can be PART TEMP RANGE PIN-PACKAGE adjusted from 125kHz to 500kHz. Additional features include adjustable UVLO, soft-start, MAX16812ATI+ -40C to +125C 28 TQFN-EP* external enable/disable input, thermal shutdown, a 1.238V +Denotes a lead(Pb)-free/RoHS-compliant package. 1% accurate buffered reference, and an on-chip oscillator. *EP = Exposed pad. An internal 5.2V linear regulator supplies up to 20mA to Simplified Diagram power external devices. The MAX16812 is available in a thermally enhanced 5mm C H REG x 5mm, 28-pin TQFN-EP package and is specified over DOUT R CS VOUT the automotive -40C to +125C temperature range. C OUT R SRC Applications LV SRC V IN IN Architectural and Industrial Lighting GT C IN EN RT DRV MAX16812 RT SLP R TGRM L REG C SLP TGRM CTGRM DIM COMP R C OV1 COMP1 VOUT R OV2 RCOMP1 R COMP2 Typical Application Circuit and Pin Configuration appear BUCK-BOOST CONFIGURATION at end of data sheet. 19-0880 Rev 1 4/14 CS- OV CS+ SGND DGT AGND DD H REG REF HV REFI CS OUT LX FBMAX16812 Integrated High-Voltage LED Driver with Analog and PWM Dimming Control Absolute Maximum Ratings (All voltages are referenced to AGND, unless otherwise noted.) DD to LV ...................................................................-1V to +80V SGND ...................................................................-0.3V to +0.3V Maximum Current into Any Pin (except LX, SRC) ...........20mA IN, EN, LX, DIM .....................................................-0.3V to +80V Maximum Current into LX and SRC ......................................+2A L REG, GT, DRV ....................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A RT, REF, REFI, CS OUT, FB, COMP, SRC, 28-Pin TQFN 5mm x 5mm SLP, TGRM, OV ..................................................-0.3V to +6V (derate 34.65mW/C* above +70C) .........................2759mW LV, HV, CS-, CS+, DGT, DD, H REG ..................-0.3V to +80V Operating Temperature Range ......................... -40C to +125C CS+, DGT, H REG to LV ......................................-0.3V to +12V Junction Temperature ......................................................+150C CS- to LV ..............................................................-0.3V to +0.3V Storage Temperature Range ............................ -65C to +150C CS+ to CS- ............................................................-0.3V to +12V Lead Temperature (soldering, 10s) .................................+300C *As per JEDEC51 standard (multilayer board). 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 = V = 12V, C = 3.3F, C = 1F, C = 47nF, V = 0V, R = 0.2, T = T = -40C to +125C, unless IN EN L REG H REG REF TGRM SRC A J otherwise noted. Typical values are at T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage Range V 5.5 76.0 V IN Quiescent Supply I V = 1V, V = 0V 0.3 2.5 mA Q TGRM DIM Shutdown Supply Current I V 300mV 20 45 A SHDN EN Internal MOSFET On-Resistance R I = 1A, V > 10V, V = V = 5V 0.2 0.4 DSON LX IN GT DRV Output Current Accuracy I I = 350mA, R = 1 -5 +5 % LED LED CS Peak Switch Current Limit I 2.6 3.1 3.6 A LXLIM Hiccup Switch Current 6 A Switch Leakage Current I V = 0V, V = 76V, V = 0V 1 10 A LXLEAK EN LX GT UNDERVOLTAGE LOCKOUT IN Undervoltage Lockout UVLO V rising 4.6 4.9 5.3 V IN UVLO Hysteresis 100 mV EN Threshold Voltage V V rising 1.2 1.38 1.6 V EN THUP EN EN Hysteresis 100 mV REFERENCE (REF) AND LOW-SIDE LINEAR REGULATOR (L REG) Startup Response Time t V or V rising 50 s POR IN EN Reference Voltage V I = 10A 1.190 1.238 1.288 V REF REF Reference Soft-Start Charging I V = 0V 25 40 60 A REF SLEW REF Current L REG Supply Voltage V = 7.5V, I = 1mA 4.9 5.2 5.5 V IN L REG L REG Load Regulation I = 20mA 20 L REG L REG Dropout Voltage I = 25mA 400 mV L REG Maxim Integrated 2 www.maximintegrated.com