RT9284AGJ5E Richtek

RT9284A/B Tiny Package, High Performance, Constant Current Switching Regulator for White LED General Description Features zz z zz V Operating Range : 2.7V to 5.5V IN The RT9284A/B is a compact, high efficient and high zz z zz Maximum Output Voltage up to 20V integration LED driver. Internal 22V MOSFET can support zz z zz Dimming with Zero-inrush and Wide Frequency 2 to 5 White LEDs for backlighting and camera flashing. Range of 100 to 100kHz Highly integration and internal compensation network zz z zz Over Voltage Protection minimizes as 5 external component counts. Optimized zz z zz Output Current up to 100mA at V : 12V OUT operation frequency can meet the requirement of small zz z zz Zero Shutdown Supply Current LC filters value and low operation current with high zz z zz Minimize the External Component efficiency. Internal soft start function can reduce the inrush zz z zz Small LC Filter current. Tiny package type of TSOT-23-5 and TSOT-23-6 zz z zz Internal Soft Start packages provide the best solution for PCB space saving zz z zz RoHS Compliant and 100% Lead (Pb)-Free and total BOM cost. Applications Ordering Information z Camera Flash White LED (- ) RT9284 z Mobile Phone, Smart Phone LED Backlight Package Type z PDA LED Backlight J5 : TSOT-23-5 J6 : TSOT-23-6 z Digital Still Camera z Camcorder Lead Plating System P : Pb Free G : Green (Halogen Free and Pb Free) Pin Configurations OVP Voltage TOP VIEW 15 : 15V VDD EN 20 : 20V 5 4 FB Voltage A : 1.235V 23 B : 0.25V LX GND FB Note : Richtek products are : TSOT-23-5 RoHS compliant and compatible with the current require- VDD OVP EN ments of IPC/JEDEC J-STD-020. 6 5 4 Suitable for use in SnPb or Pb-free soldering processes. 23 Marking Information LX GND FB For marking information, contact our sales representative TSOT-23-6 directly or through a Richtek distributor located in your area. www.richtek.com DS9284A/B-07 April 2011 1RT9284A/B Typical Application Circuit L1 D1 OVP 4.7uH to 22uH SS0520 15V + C1 C2 I V LED IN 1uF 1uF/16V 2.7V to 5.5V RT9284 6 1 VDD LX 4 5 Dimming EN OVP Control 2 100Hz-100kHz 3 GND FB R1 Figure 1. Application for Driving 3 Series WLEDs L1 D1 OVP 4.7uH to 22uH SS0520 18V + C1 C2 I V IN LED 1uF 1uF/25V 2.7V to 5.5V R2 RT9284 600k 6 1 VDD LX 4 5 EN Dimming OVP OVP 15V Control 2 100Hz-100kHz 3 GND FB R1 Figure 2. Application for Driving 4 Series WLEDs D1 L1 OVP 4.7uH to 22uH SS0520 20V + V C1 C2 I IN LED 1uF 1uF/25V 2.7V to 5.5V RT9284B 6 1 VDD LX 4 5 EN Dimming OVP Control 2 100Hz-100kHz 3 GND FB V = 0.25V FB R1 Figure 3. Application for Driving 5 Series WLEDs D1 L1 OVP 4.7uH to 22uH SS0520 15V V OUT 12V + V C1 C2 IN R1 1uF 1uF/16V 2.7V to 5.5V 130k RT9284A 6 1 VDD LX 4 5 EN OVP 2 GND 3 FB V = 1.235V FB R2 15k Figure 4. Application for Constant Output Voltage DS9284A/B-07 April 2011 www.richtek.com 2