EVALUATION KIT AVAILABLE 2MHz, High-Brightness LED MAX16822A/MAX16822B Drivers with Integrated MOSFET and High-Side Current Sense General Description Benefits and Features The MAX16822A/MAX16822B step-down constant-cur- Cost-Effective Solution for Wide Range of LED rent high-brightness LED (HB LED) drivers provide a Lighting Applications cost-effective design solution for automotive 6.5V to 65V Input Voltage Range interior/exterior lighting, architectural and ambient light- Output Current Up to 500mA ing, LED bulbs, and other LED illumination applications. 3% LED Current Accuracy The MAX16822A/MAX16822B operate from a +6.5V to Selectable Dimming Options: Linear or PWM +65V input-voltage range and can provide an output Minimal Component Count Saves Cost and Space current up to 350mA, if operated up to a temperature of On-Board 65V, 0.85 Power MOSFET +125C, or up to 500mA, if operated up to a tempera- Resistor-Programmable Constant LED Current ture of +105C. A high-side current-sense resistor Integrated High-Side Current Sense with 200mV adjusts the output current and a dedicated pulse-width Current-Sense Reference modulation (PWM) input enables pulsed LED dimming Hysteretic Control: Up to 2MHz Switching over a wide range of brightness levels. Frequency These devices are well suited for applications requiring Protection Features and Wide Operating a wide input-voltage range. The high-side current sens- Temperature Range Improves Reliability ing and an integrated current-setting circuitry minimize Thermal-Foldback Protection Dims LEDs to the number of external components while delivering an Minimize Overheating average output current with 3% accuracy. A hysteretic Thermal-Shutdown Protection control method ensures excellent input supply rejection Available in an 8-Pin SO Package and fast response during load transients and PWM dim- Operation Over -40C to +125C Temperature ming. The MAX16822A allows 10% current ripple and Range the MAX16822B allows 30% current ripple. Both devices operate up to a switching frequency of 2MHz, Ordering Information thus allowing the use of small-sized components. The MAX16822A/MAX16822B offer an analog dimming PART TEMP RANGE PIN-PACKAGE feature that reduces the output current by applying an MAX16822AASA+ -40C to +125C 8 SO external DC voltage below the internal 2V threshold volt- MAX16822AASA/V+ -40C to +125C 8 SO age from TEMP I to GND. TEMP I also sources 25A to a negative temperature coefficient (NTC) thermistor con- MAX16822BASA+ -40C to +125C 8 SO nected between TEMP I and GND, thus providing an +Denotes a lead(Pb)-free/RoHS-compliant package. analog thermal-foldback feature that reduces the LED /V denotes an automotive qualified part. current when the temperature of the LED string exceeds Typical Application Circuit a specified temperature point. An additional feature includes thermal-shutdown pro- D1 tection that turns off the LX driver when the junction temperature exceeds +165C. HB LEDs V The MAX16822A/MAX16822B operate over the -40C to IN R L1 SENSE +125C automotive temperature range and are available in an 8-pin SO package. C2 Applications Architectural, Industrial, and Ambient Lighting 1 8 CS TEMP I Automotive RCL, DRL, and Fog Lights ON * NTC 2 7 OFF Heads-Up Displays IN DIM MAX16822A C1 MAX16822B Indicator and Emergency Lighting 3 6 GND LX 4 5 PGND LX Pin Configuration appears at end of data sheet. * OPTIONAL 19-4141 Rev 4 2/152MHz, High-Brightness LED MAX16822A/MAX16822B Drivers with Integrated MOSFET and High-Side Current Sense Absolute Maximum Ratings IN, CS, LX, DIM to GND .........................................-0.3V to +70V Junction-to-Ambient Thermal Resistance ( ) (Note 1)...136C/W JA TEMP I to GND .......................................................-0.3V to +6V Pin-to-Pin ESD Ratings......................................................2.5kV PGND to GND ......................................................-0.3V to +0.3V Operating Temperature Range CS to IN .................................................................-0.3V to +0.3V 350mA (max) Output Current ........................-40C to +125C Maximum Current into Any Pin 500mA (max) Output Current ........................-40C to +105C (except IN, LX, and PGND).............................................20mA Junction Temperature......................................................+150C Continuous Power Dissipation (T = +70C) Storage Temperature Range .............................-65C to +150C A 8-Pin SO (derate 7.4mW/C above +70C)...............588.2mW Lead Temperature (soldering, 10s) .................................+300C Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four- layer board. For detailed information on package thermal considerations, see www.maximintegrated.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 (V = +24V, V = V , T = T = -40C to +125C, unless otherwise noted. Typical values are at T = +25C.) IN DIM IN A J A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input-Voltage Range V 6.5 65 V IN Ground Current No switching 1.5 mA Supply Current V < 0.6V, V = 12V 350 A DIM IN UNDERVOLTAGE LOCKOUT (UVLO) V = V - 100mV, V rising from 4V CS IN IN 6.25 6.5 until V < 0.5V LX IN Undervoltage Lockout UVLO V V = V - 100mV, V falling from 6.5V CS IN IN 6 until V > 0.5V LX IN Undervoltage-Lockout Hysteresis 0.5 V SENSE COMPARATOR MAX16822A, V - V rising from 140mV IN CS 201 210 216 until V > 0.5V LX IN Sense Voltage Threshold High V mV SNSHI MAX16822B, V - V rising from 140mV IN CS 218 230 236 until V > 0.5V LX IN MAX16822A, V - V falling from IN CS 185 190 198 260mV until V < 0.5V LX IN Sense Voltage Threshold Low V mV SNSLO MAX16822B, V - V falling from IN CS 166 170 180 260mV until V < 0.5V LX IN Falling edge of V - V from 140mV to IN CS Propagation Delay to Output High t 50 ns DPDH 260mV to V > 0.5V LX IN Rising edge of V - V from 260mV to CS IN Propagation Delay to Output Low t 50 ns DPDL 140mV to V < 0.5V LX IN CS Input Current I V - V = 200mV 3.5 A CSIN IN CS www.maximintegrated.com Maxim Integrated 2