RT9293 Small Package, High Performance, Asynchronies Boost for 10 WLED Driver General Description Features zz z zz VIN Operating Range : 2.5V to 5.5V The RT9293 is a high frequency, asynchronous boost zz z zz Internal Power N-MOSFET Switch converter. The internal MOSFET can support up to 10 zz z zz Wide Range for PWM Dimming (100Hz to200kHz) White LEDs for backlighting and OLED power application, zz z zz Minimize the External Component Counts and the internal soft start function can reduce the inrush zz z zz Internal Soft Start current. The device operates with 1-MHz fixed switching zz z zz Internal Compensation frequency to allow small external components and to zz z zz Under Voltage Protection simplify possible EMI problems. For the protection, the zz z zz Over Voltage Protection RT9293A provides 50V OVP and the RT9293B provides zz z zz Over Temperature Protection 50V/20V OVP to allow inexpensive and small-output zz z zz Small TSOT-23-6 and 8-Lead WDFN Packages capacitors with lower voltage ratings. The LED current is zz z zz RoHS Compliant and Halogen Free initially set with the external sense resistor R . The SET RT9293 is available in the tiny package type TSOT-23-6 Applications and WDFN-8L 2x2 packages to provide the best solution z Cellular Phones for PCB space saving and total BOM cost. z Digital Cameras Ordering Information z PDAs and Smart Phones and MP3 and OLED. - z Portable Instruments RT9293 ( ) Package Type J6 : TSOT-23-6 Pin Configurations QW : WDFN-8L 2x2 (W-Type) (TOP VIEW) Lead Plating System G : Green (Halogen Free and Pb Free) VIN VOUT EN OVP Voltage 6 5 4 Default : 50V (RT9293A/B) 20 : 20V (RT9293B) 23 Feedback Voltage Reference LX GND FB A : 104mV B : 300mV TSOT-23-6 Note : Richtek products are : 1 8 LX GND VIN 2 7 NC RoHS compliant and compatible with the current require- 3 6 VOUT FB 9 EN 4 5 GND ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. WDFN-8L 2x2 Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. DS9293-01 April 2011 www.richtek.com 1 GND+ - RT9293 Typical Application Circuit L D 22H to 47H V OUT LX VOUT C OUT 1F V VIN IN C IN RT9293 10 WLEDs 2.2F Chip Enable EN GND FB R SET Functional Pin Description Pin No. Pin Name Pin Function RT9293 GJ6 RT9293 GQW 1 8 LX Switching Pin. 1, 5, Ground Pin. The exposed pad must be soldered to a large 2 GND 9 (Exposed pad) PCB and connected to GND for maximum power dissipation. 3 6 FB Feedback Pin, put a resistor to GND to setting the current. 4 4 EN Chip Enable (Active High). 5 3 VOUT Output Voltage Pin. 6 2 VIN Input Supply. -- 7 NC No Internal Connection. Function Block Diagram VIN LX UVLO OVP VOUT OCP Internal Compensation OTP Logic Control, Current- Minimum On PWM Sense Internal Time Soft Start + Driver EA GND GM Slope Compensation Shutdown PWM Enable Oscillator 20ms LPF Logic Reference Voltage V REF Bias 1A Current EN FB www.richtek.com DS9293-01 April 2011 2 + -