RT4503A

® RT4503/A Asynchronous Boost Converter for 10 WLEDs General Description The RT4503/A is a highly integrated LED driver IC capable of driving 10 WLEDs in series. It is composed of a current mode Boost converter integrated with a 36V/1.2A power switch. The RT4503/A supports a wide input voltage range from 2.5V to 5.5V and runs at a fixed frequency of 550kHz. The LED current is set via an external resistor and the feedback voltage is regulated to 200mV. For brightness dimming, the RT4503A supports 32 steps pulse dimming which determines the feedback reference voltage, and RT4503 support PWM dimming which determines the feedback reference voltage. Applications  Cellular Phones  Digital Cameras  Probable Instruments Features  2.5V to 5.5V Input Voltage Range  36V Open LED Protection for 10 WLEDs  Pulse Dimming Brightness Control  200mV Reference Voltage with ±2% Accuracy  550kHz Switching Frequency  Built-In Soft-Start  Over-Temperature Protection  Internal Compensation  Current Limit Ordering Information RT4503/A Package Type QW : WDFN-6L 2x2 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) Note : RT4503 : PWM Dimming RT4503A : Pulse Dimming Richtek products are :  RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020.  Suitable for use in SnPb or Pb-free soldering processes. Simplified Application Circuit VIN L LX VIN RT4503/A EN GND COMP* FB … * : COMP pin for RT4503 only. Copyright ©2015 Richtek...