MIC4802YME Microchip

MIC4802 High Efficiency 800mA Single Channel Linear WLED Driver with Ultra Fast PWM Control General Description Features The MIC4802 is a high efficiency White LED (WLED) High Efficiency (no Voltage Boost losses) driver designed to drive a single LED up to 800mA. The Ultra Fast PWM control (200Hz to 500kHz) MIC4802 constant current driver is designed to drive high Input voltage range: 3.0V to 5.5V power LEDs in various lighting applications. The MIC4802 Dropout of 280mV at 800mA provides the highest possible efficiency as this architecture has no switching losses present in traditional charge Programmable LED current with external resistor pumps or inductive boost circuits. It features a typical Current accuracy of 1% typical dropout of 280mV at 800mA. This allows the LEDs to be driven directly from the voltage source eliminating Applications switching noise/losses present with the use of boost Bill board displays circuitry. The high accuracy (1% Typical) current regulated WLED channel ensures uniform display Marquee displays illumination under all conditions. The brightness is Instrument displays controlled through an Ultra Fast PWM Control interface Architectural lighting operating down to less than 1% duty cycle. The MIC4802 is available in the 8-pin SOIC Epad package with a junction temperature range of -40 C to +125C. Datasheets and support documentation can be found on Micrels web site at: www.micrel.com. Typical Application High Current Lighting Schematic Ultra Fast PWM is a trademark of Micrel, Inc. Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel Inc. MIC4802 Ordering Information Part Number Temperature Range Package MIC4802YME 40C to +125C 8-Pin EPAD SOIC Pin Configuration 8-Pin Epad SOIC (ME) (Top View) Pin Description Pin Number Pin Name Pin Function 1 VIN Voltage Input. Connect at least 2.2F ceramic capacitor between VIN and GND. 2 EN Enable LED drivers. This pin can be used as a PWM input for dimming of WLEDs. Do not leave floating. 3 RSET An internal 1.27V reference sets the nominal maximum WLED current. Example, apply a 6.19k resistor between RSET and GND to set LED current to 830mA at 100% duty cycle. 4 GND Ground. 5 D1 LED1 driver input. Connect LED anode to VIN and cathode to this pin. All D1 pins must be connected to the LED. 6 D1 LED1 driver input. Connect LED anode to VIN and cathode to this pin. All D1 pins must be connected to the LED. 7 D1 LED1 driver input. Connect LED anode to VIN and cathode to this pin. All D1 pins must be connected to the LED. 8 D1 LED1 driver input. Connect LED anode to VIN and cathode to this pin. All D1 pins must be connected to the LED. EPAD HS PAD Heat sink pad. Not internally connected. Connect to ground. M9999-013111-B January 2011 2