SC4541 High Frequency LED Driver with Integrated Schottky and Simple Interconnect POWER MANAGEMENT Description Features The SC4541 is a fully integrated, high voltage boost (step- V Range 2.9V to 22V IN up) and buck (step-down) LED driver. The input voltage V Range Up to 25V OUT range is 2.9V to 22V with output voltage up to 25V. The I Range: OUT device is capable of driving up to 7 white LEDs. The high Up to 100mA (Boost) side sense enables a single-wire LED connection by taking Up to 200mA (Buck) advantage of the available system ground. This reduces connector cost and complexity. Drives Up to 7 Series WLEDs (Boost) Drives Up to 5 Series WLEDs (Buck) The device includes a current mode PWM controller, Integrated Schottky Rectifier 260mA power switch, and high performance Schottky Single-Wire LED Connect rectifier. The LED driver eliminates external compensation Current Mode Control components for minimum solution size. Frequency 2.0MHz The wide input voltage range and low standby current are No External Compensation ideal for portable devices. The high input voltage allows Direct PWM Dimming direct connection to multi-cell battery packs which 100:1 Range at 500Hz increases operating efficiency and extends battery life. Open-LED Protection 27V Low Shutdown Current < 1A Output current is programmed with an external sense Package Options: resistor up to 100mA (Boost) or 200mA (Buck). The device Low Profile MLPD-UT, 6-pin 2x2 x0.6(mm) provides 5% constant current accuracy across the entire operating temperature range. SOT23, 6-pin 2.9x2.8 x1.45(mm) Lead-free, Halogen-Free and WeEE/RoHS Compliant A logic level PWM dimming signal may be applied directly to the enable (EN) pin - for direct PWM dimming with a wide dimming range. Output OVP (over voltage protec- Applications tion) protects the SC4541 from open circuit faults in the LED string or connector. External OVP programming resistors Keypad Illumination are not required. DSC and DSLR Display Backlight Cellular Handsets The SC4541 is available in low profile MLPD-UT and Automotive Lighting SOT23,6-pin packages. The device is rated across the temperature range -40C to +85C. Typical Application Circuit Boost Topology I up to 100mA OUT V 2.9V to 22V IN L1 10F C1 1F V Up to 25V OUT SW IN OUT C2 RS SC4541 10 1F FB EN GND PWM Dimming 7 WLED 20mA Version 1.3 1 2011 Semtech CorporationSC4541 Pin Configuration, SOT23-6 Pin Configuration, MLPD-UT6 OUT FB EN 6 5 4 IN 1 6 EN TOP VIEW FB GND 2 5 Top View T 3 4 OUT SW 1 2 3 SW GND IN SOT23, 6 Lead MLPD-UT: 2 x 2(mm) 6 Lead = 150 C/W JA = 75 C/W JA Marking Information, MLPD-UT6 Marking Information, SOT23-6 FR7 = Code for SC4541 LK5A = Code for SC4541 EW = Datecode Eyww = Datecode Ordering Information Device Package (1,2) SC4541SKTRT SOT23-6 (1,2) SC4541ULTRT 2 x 2 x 0.6(mm) MLPD-UT6 SC4541EVB-1 Evaluation Board, SOT23-6 SC4541EVB-2 Evaluation Board, MLPD-UT6 Notes: (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Available in lead-free package only. Device is WEEE/RoHS compliant and halogen-free. 2