19-4032; Rev 1; 7/09 KIT ATION EVALU E L B AVAILA High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming The MAX16815/MAX16828 current regulators operate from a 6.5V to 40V input voltage range and deliver up to 100mA (MAX16815) or 200mA (MAX16828) to highbrightness LED (HB LED) loads. The output current is adjusted by using an external current-sense resistor in series with the LEDs. The MAX16815/MAX16828’s dimming input allows wide-range “pulsed” PWM operation. An on-board pass element minimizes external components while providing ±3.5% output-current accuracy. The MAX16815/MAX16828 are available in a thermally enhanced, 3mm x 3mm, 6-pin TDFN package with exposed pad and in an 8-pin SO package with exposed pad; they are specified over the automotive 40°C to +125°C temperature range. Applications Automotive Interior: Map, Courtesy, and Cluster Lighting Automotive Exterior: Rear Combination Lights (RCLs) Features ♦ 6.5V to 40V Operating Range ♦ Adjustable LED Current MAX16815: 35mA to 100mA MAX16828: 35mA to 200mA ♦ ±3.5% LED Current Accuracy ♦ High-Voltage DIM Input for Dimming Interface ♦ Integrated Pass Element with Low-Dropout Voltage (0.4V typ) ♦ 5V Regulated Output with 4mA Source Capability ♦ Thermal Shutdown ♦ Output Short-Circuit Protection ♦ Available in Small, Thermally Enhanced, 3mm x 3mm, 6-Pin TDFN and 8-Pin SO with Exposed Pad Packages ♦ -40°C to +125°C Operating Temperature Range Ordering Information Emergency Vehicle Warning Lights Signage and Indicators Ambient and Architectural Lighting LED Bulbs Display Backlighting PART TEMP RANGE PIN-PACKAGE MAX16815ATT+ -40°C to +125°C MAX16815ASA+ -40°C to +125°C 8 SO-EP* MAX16828ATT+ -40°C to +125°C 6 TDFN-EP* MAX16828ASA+ -40°C to +125°C 8 SO-EP* 6 TDFN-EP* +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Pin Configurations appear at end of data sheet. Typical Operating Circuit Simplified Diagram +6.5V TO +40V IN 6.5V TO 40V OUT IN C1 0.1μF +5V REG V5 +5V REG LEDs V5 C2 EN MAX16815 MAX16828 MAX16815 MAX16828 CS+ DIM CSGND LEDs 0.1μF CS+ RSENSE PWM DIMMING OUT PWM DIMMING RSENSE DIM CSGND ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX16815/MAX16828 General Description MAX16815/MAX16828 High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming ABSOLUTE MAXIMUM RATINGS IN to GND ...............................................................-0.3V to +45V CS+, CS-, V5 to GND ...............................................-0.3V to +6V DIM, EN to GND...........................................-0.3V to (VIN + 0.3V) OUT Short Circuited to GND Duration (at VIN = +16V) .......................................................60 minutes Maximum Current into Any Pin (except IN and OUT).......±20mA Continuous Power Dissipation (TA = +70°C) 6-Pin, 3mm x 3mm TDFN (derate 18.2mW/°C above +70°C) ..........................1454.5mW 8-Pin SO (derate 23.3mW/°C above +70°C)...........1860.5mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Junction-to-Case Thermal Resistance (θJC) (Note 1) 6-Pin, 3mm x 3mm TDFN ...............................................9°C/W 8-Pin SO .........................................................................7°C/W Junction-to-Ambient Thermal Resistance (θJA) (Note 1) 6-Pin, 3mm x 3mm TDFN .............................................42°C/W 8-Pin SO .......................................................................43°C/W Storage Temperature Range .............................-60°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. 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 (VIN = 12V, VEN = 12V (SO only), CV5 = 0.1µF to GND, IV5 = 0, VDIM = 4V, VCS- = 0V (SO only), connect RSENSE = 2Ω (MAX16815) and RSENSE = 1Ω (MAX16828) between CS+ and GND. TA = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER Supply Voltage Range Ground Current Shutdown Supply Current Guaranteed Output Current SYMBOL VIN IG I SHDN I OUT Output Current Accuracy Dropout Voltage VDO Output Current Slew Rate Short-Circuit Current CONDITIONS (Note 3) MIN TYP 6.5 MAX UNITS 40.0 V ILOAD = 100mA 0.82 2 ILOAD = 200mA 1 2 35 70 VEN 0.6V (SO only) RSENSE = 2 (MAX16815) 100 RSENSE = 1 (MAX16828) 200 mA μA mA 35mA < I OUT < 100mA (MAX16815) ±3.5 35mA < I OUT < 200mA (MAX16828) ±3.5 % I OUT = 100mA (current pulsed), 12V < VIN < 40V (MAX16815) (Note 4) 0.1 0.4 I OUT = 100mA (current pulsed), 6.5V < VIN < 12V (MAX16815) (Note 4) 0.1 0.6 I OUT = 200mA (current pulsed), 12V < VIN < 40V (MAX16828) (Note 5) 0.27 0.55 I OUT = 200mA (current pulsed), 6.5V < VIN < 12V (MAX16828) (Note 5) 0.27 0.7 Current rising 9.7 Current falling 9.7 V mA/μs VOUT = 0V, VIN = 12V, MAX16815 130 200 270 VOUT = 0V, VIN = 12V, MAX16828 250 300 350 -1 -0.2 mA EN INPUT (SO ONLY) EN Input Current I EN -2.5 EN Input-Voltage High VIH 2.8 EN Input-Voltage Low VIL 2 _______________________________________________________________________________________ μA V 0.6 V High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming (VIN = 12V, VEN = 12V (SO only), CV5 = 0.1µF to GND, IV5 = 0, VDIM = 4V, VCS- = 0V (SO only), connect RSENSE = 2Ω (MAX16815) and RSENSE = 1Ω (MAX16828) between CS+ and GND. TA = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VRSNS = VCS+ for TDFN package; VRSNS = VCS+ - VCS- for SO package 193 200 207 mV CS- Voltage Range SO only -0.3 Input Current (CS+) VCS+ = 220mV Input Current (CS-) VCS+ = 220mV (SO only) -50 17.2 VDIM = 0V -2.5 -1.0 CURRENT SENSE Regulated RSENSE Voltage VRSNS DIM Input Current DIM Input-Voltage High VIH 2.7 +4.7 V 7 μA μA -0.2 2.8 DIM Input-Voltage Low VIL Turn-On Time t ON After VDIM rising to 4V (Note 7) Turn-Off Time t OFF After VDIM falling to 0.6V (Note 7) μA V 0.6 V 100 μs 55 μs THERMAL OVERLOAD Thermal-Shutdown Temperature Thermal-Shutdown Hysteresis +159 °C 24 °C +5V REGULATOR Output-Voltage Load Regulation VV5 VV5 Output Voltage V5 Short-Circuit Current (Note 8) 0 < I V5 < 4mA VV5 = 0 (Note 9) 4.8 5.0 5.2 V 12 20 mV/mA 15 mA Note 2: All devices are 100% production tested at TA = +25°C. Limits over the operating temperature range are guaranteed by design. Note 3: Resistors were added from OUT to CS+ to aid with power dissipation. Note 4: Dropout is measured as follows: Connect RO from OUT to CS+. Connect RSENSE = 2Ω (MAX16815) from CS+ to GND (for TDFN) or from CS+ to CS- (for SO). Set VIN = 12V (record VOUT1 = VOUT). For VIN = 40V, use RO = 360Ω; for VIN = 6.5V, use RO = 56Ω. Reduce VIN until VOUT = 0.97 x VOUT1 (record as VIN2 and VOUT2). ΔVDO = VIN2 - VOUT2. Note 5: Dropout is measured as follows: Connect RO from OUT to CS+. Connect RSENSE = 1Ω (MAX16828) from CS+ to GND (for TDFN) or from CS+ to CS- (for SO). Set VIN = 12V (record VOUT1 = VOUT). For VIN = 40V, use RO = 180Ω; for VIN = 6.5V, use RO = 27Ω. Reduce VIN until VOUT = 0.97 x VOUT1 (record as VIN2 and VOUT2). ΔVDO = VIN2 - VOUT2. Note 6: IV5 = 0mA. Note 7: tON time includes the delay and the rise time needed for IOUT to reach 90% of its final value. tOFF time is the time needed for IOUT to drop below 10%. See the Typical Operating Characteristics. tON and tOFF are tested with 100Ω (MAX16815) or 51Ω (MAX16828) from OUT to CS+. Note 8: Current regulation varies with V5 load (see the Typical Operating Characteristics). Note 9: Thermal shutdown does not function if V5 is shorted to ground. _______________________________________________________________________________________ 3 MAX16815/MAX16828 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VIN = 12V, TA = +25°C, unless otherwise noted.) OUTPUT CURRENT vs. TEMPERATURE 150 MAX16815 ILOAD = 100mA 100 MAX16815 AND MAX16828 ILOAD = 35mA 50 0.3 0.2 0.1 MAX16815 toc03 400 350 300 MAX16828 250 200 MAX16815 150 100 50 0 0 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 35 40 45 50 55 60 65 70 75 80 85 90 95 100 TEMPERATURE (°C) OUTPUT CURRENT (mA) INPUT VOLTAGE (V) DROPOUT VOLTAGE vs. TEMPERATURE +5V REGULATOR OUTPUT vs. TEMPERATURE VCS+ (FOR TDFN) OR VCS+ - VCS- (FOR SO) vs. IV5 0.2 0.1 5.1 NO LOAD IV5 = 1mA 5.0 4.9 IV5 = 5mA MAX16815 ILOAD = 100mA 0 4.8 0.4 10 15 20 25 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) TEMPERATURE (°C) +5V REGULATOR OUTPUT vs. VIN MAX16815 200Hz DIMMED OPERATION MAX16815 toc07 ILOAD = 100mA, VIN = 12V DIM PULSED AT 200Hz 150% DUTY CYCLE 5.1 NO LOAD IV5 = 1mA 0.3 0.2 0.1 0 1 2 3 4 MAX16815 200Hz DIMMED OPERATION (EXPANDED) MAX16815 toc09 VDIM 10V/div ILOAD = 100mA, VIN = 12V DIM PULSED AT 200Hz 150% DUTY CYCLE VDIM 10V/div 0V 0V ILOAD 50mA/div ILOAD 50mA/div 0 0 5.0 4.9 IV5 = 5mA 4.8 5 10 15 20 25 30 35 40 1ms/div 10μs/div VIN (V) 4 40 MAX16815 AND MAX16828 MAX16815 toc08 MAX16815 AND MAX16828 35 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 5.2 30 MAX16815 toc06 MAX16815 AND MAX16828 VCS+ (FOR TDFN) OR VCS+ - VCS- (FOR SO) (V) 0.3 5 MAX16815 toc05 MAX16828 ILOAD = 200mA 0.4 5.2 5V REGULATOR OUTPUT (V) MAX16815 toc04 0.5 DROPOUT VOLTAGE (V) MAX16815 AND MAX16828 IOUT UP TO 100mA FOR MAX16828 OUTPUT CURRENT (mA) 200 0.4 MAX16815 toc02 MAX16815 toc01 MAX16828 ILOAD = 200mA VCS+ (FOR TDFN) OR VCS+ - VCS- (FOR SO) (V) OUTPUT CURRENT (mA) 250 OUTPUT CURRENT vs. INPUT VOLTAGE VCS+ (FOR TDFN) OR VCS+ - VCS- (FOR SO) vs. OUTPUT CURRENT 300 5V REGULATOR OUTPUT (V) MAX16815/MAX16828 High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming _______________________________________________________________________________________ High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming MAX16815 200Hz DIMMED OPERATION (EXPANDED) MAX16828 200Hz DIMMED OPERATION MAX16815 toc11 MAX16815 toc10 ILOAD = 100mA, VIN = 12V DIM PULSED AT 200Hz 50% DUTY CYCLE VDIM 10V/div ILOAD = 200mA, VIN = 12V DIM PULSED AT 200Hz 50% DUTY CYCLE 0V 0V ILOAD 50mA/div ILOAD 200mA/div 0 0 1ms/div 20μs/div MAX16828 200Hz DIMMED OPERATION (EXPANDED) MAX16828 200Hz DIMMED OPERATION (EXPANDED) MAX16815 toc12 ILOAD = 200mA, VIN = 12V DIM PULSED AT 200Hz 50% DUTY CYCLE 20μs/div VDIM 10V/div MAX16815 toc13 VDIM 10V/div ILOAD = 200mA, VIN = 12V DIM PULSED AT 200Hz 50% DUTY CYCLE VDIM 10V/div 0V 0V ILOAD 200mA/div 0 ILOAD 200mA/div 0 20μs/div _______________________________________________________________________________________ 5 MAX16815/MAX16828 Typical Operating Characteristics (continued) (VIN = 12V, TA = +25°C, unless otherwise noted.) High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming MAX16815/MAX16828 Pin Description PIN NAME FUNCTION TDFN SO 1 6 DIM Pulsed Dimming Input. Drive DIM low to turn off output current (LED current). Drive DIM high to turn on the output current (LED current). DIM is pulled high to VIN when left unconnected. — 7 EN Enable Input. Drive EN high to enable the output. For the TDFN package, this input is not accessible and always high. 2 8 OUT 3 1 IN 4 2 CS+ LED Current-Sense Amplifier Positive Input. For the SO package version, connect the current-sense resistor between this pin and CS-; for the TDFN version, connect it between this pin and ground. — 3 CS- LED Current-Sense Amplifier Negative Input. Connect to ground. 5 4 V5 +5V Regulated Output. Connect a 0.1μF (min) capacitor from V5 to GND. 6 5 GND — — EP Current-Regulated Output Positive Input Supply. Bypass IN with a 0.1μF (min) capacitor to GND. Ground Exposed Pad. Connect to a large ground plane for effective power dissipation. Do not use as the only ground connection. TDFN Functional Diagram DIM IN 0.8μA 1.2V V5 BANDGAP AND 5V REGULATOR IREG P OUT THERMAL SHUTDOWN CS+ DIFF AMP GND MAX16815 MAX16828 6 _______________________________________________________________________________________ High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming DIM IN 0.8μA EN V5 1.2V BANDGAP AND 5V REGULATOR IREG P OUT THERMAL SHUTDOWN CS+ DIFF AMP GND MAX16815 MAX16828 Detailed Description CS- Applications Information +5V Regulator Programming the LED Current The MAX16815/MAX16828 include a fixed +5V output regulator that delivers up to 4mA of load current throughout the 6.5V to 40V input voltage range. Connect a 0.1µF compensation capacitor from V5 to ground. Shorting V5 to ground disables the thermal shutdown. V5 stays on during PWM dimming. The MAX16815/MAX16828 use a sense resistor across CS+ and GND for the TDFN package or across CS+ and CS- for the SO package, to set the LED current. The LED current is given by ILED = VRSNS/RSENSE. Thermal Protection The MAX16815/MAX16828 enter a thermal-shutdown mode in the event of overheating. This typically occurs in overload or output short-circuit conditions. If the junction temperature exceeds TJ = +159°C (typ), the internal thermal-protection circuitry turns off the series pass device. The MAX16815/MAX16828 recover from thermal-shutdown mode once the junction temperature drops by 24°C (typ). The devices therefore protect themselves by thermal cycling in the event of a shortcircuit or overload condition. Shorting V5 to ground disables the thermal shutdown. Input-Voltage Considerations For proper operation, the minimum input voltage must always be: VIN(MIN) ≥ VRSNS(MAX) + VFT(MAX) + ΔVDO(MAX) where VFT(MAX) is the total forward voltage of all series connected LEDs. The minimum operating voltage of the device is +6.5V. The device operates below +6.5V; however, output current may not meet the full regulation specification (see the Typical Operating Characteristics) and the V5 regulator will drop below 5V. Low-Frequency PWM Dimming at the Output Provide a pulse to the dimming input (DIM) of the MAX16815/MAX16828 to produce a PWM output. Alternatively, connect DIM to IN and pulse IN. _______________________________________________________________________________________ 7 MAX16815/MAX16828 SO Functional Diagram MAX16815/MAX16828 High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming D1 STOP D2 IN TAIL OUT R1 MAX16815 MAX16828 R2 D3 IN DIS C1 LEDs +5V REG C2 D4 DIM OUT R3 V5 CS+ ICM7555 TH TRG GND R4* RSENSE GND CS- C2 *R4 < 300kΩ Figure 1. PWM Dimming Operation with ICM7555 Timer Two Brightness Levels for TAIL/STOP Lights Figure 1 shows PWM dimming operation for the MAX16815/MAX16828 with an ICM7555 timer. The ICM7555 provides adjustable duty cycle using two external resistors and a capacitor. In TAIL operation, the output of the ICM7555 feeds into DIM and lights up the LEDs. The LED’s brightness depends on the duty cycle of the ICM7555. When VSTOP is present, DIM is pulled up to VSTOP. The PWM dimming operation is disabled and the LEDs light up to full brightness. See the ICM7555 data sheet for formulas to calculate the dimming frequency and the duty cycle. VIN IN OUT MAX16815 MAX16828 C1 LEDs V5 PWM DIMMING C2 RT R2 DIM CS+ GND R1 CS- LED Current Thermal Foldback With a minimum number of external components, the MAX16815/MAX16828 provide LED current thermal foldback using a negative temperature coefficient (NTC) thermistor. Figure 2 shows a thermistor connected to V5 and the CS+ of the MAX16815/MAX16828. As the temperature increases, the voltage drop across R2 increases, causing the LED current to decrease. ILED = [VRSNS - (R2 / RT) (VV5 - VRSNS)]/R1 Figure 2. LED Current Thermal Foldback with an NTC Thermistor Other Applications STOP operation, Q1 turns on and the output current is set by a parallel combination of R1 and R2. Figure 4 shows an application circuit with the MAX16815/ MAX16828 using a single BJT to provide high output current. For proper operation: VIN(MIN) > VCESAT(MAX) + VFT(MAX) + VRSNS The application circuit in Figure 3 implements a twolevel brightness current for TAIL/STOP lights. In TAIL operation, Q1 is off and R1 sets the output current. In where VCESAT(MAX) is the maximum saturation voltage of the external BJT and VFT(MAX) is the total forward voltage of all series connected LEDs. 8 _______________________________________________________________________________________ High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming MAX16815/MAX16828 STOP LEDs D1 OUT IN TAIL DIM MAX16815 MAX16828 VIN V5 IN Q1 OUT LEDs C2 R3 MAX16815 MAX16828 C1 C1 CS+ C2 R2 GND V5 PWM DIMMING DIM R1 CS+ Q1 GND RSENSE Z1 CS- CS- Figure 3. Two-Level Brightness with Current Level Switch for TAIL/STOP Lights Figure 4. Increased LED Current (Ampere Range) with a Single BJT D1 L1 VIN CREF REF VCC C3 IN IN OUT IN OUT OUT C2 R3 U2 LEDs MAX5094C CCOMP COMP OUT Q1 EN C4 RCOMP MAX16815 MAX16828 EN V5 C7 C6 FB MAX16815 MAX16828 C11 CS+ R5 CT/RT R4 CS EN V5 GND CS- MAX16815 MAX16828 LEDs V5 C9 C8 DIM CS+ U3 LEDs C10 DIM GND U4 DIM CS+ GND CS- R7 GND CS- R6 CT R2 Figure 5. Multichannel HB LED Drivers for LCD Backlight Chip Information Multichannel HB LED Driver Figure 5 shows an array of MAX16815/MAX16828s with independent DIM control. The MAX5094C, a currentmode PWM controller, provides the input power to each LED driver preregulated voltage to multiple MAX16815/ MAX16828 drivers. PROCESS: BiCMOS _______________________________________________________________________________________ 9 High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming MAX16815/MAX16828 Pin Configurations GND V5 CS+ TOP VIEW 6 5 4 MAX16815 MAX16828 CS+ 2 CS- 3 MAX16815 MAX16828 EP* 8 OUT 7 EN 6 DIM 5 GND SO 2 3 OUT IN DIM 1 1 V5 4 EP* + IN TDFN *EP = EXPOSED PAD Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. 10 PACKAGE TYPE PACKAGE CODE DOCUMENT NO. 8 SO-EP S8E-12 21-0111 6 TDFN-EP T633-2 21-0137 ______________________________________________________________________________________ High-Voltage, 100mA/200mA Adjustable Linear High-Brightness LED Drivers with PWM Dimming REVISION NUMBER REVISION DATE 0 2/08 Initial release. 7/09 • Added the SO package to the Ordering Information table, Electrical Characteristics, TOC 2 and 6, Pin Description table, and Functional Diagrams. • Modified the Simplified Diagram and Figures 1–4 to include the CS- pin. • Added the SO-EP Pin Configuration. 1 DESCRIPTION PAGES CHANGED — 1–4, 6–10 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11 © 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX16815/MAX16828 Revision History