AP3019A

Data Sheet WHITE LED STEP-UP CONVERTER AP3019A General Description The AP3019A is an inductor-based DC/DC converter designed to drive up to eight white LEDs in series for backlight. Only one feedback resistor is needed to control the LED current and obtain required brightness. A constant frequency 1.2MHz PWM control scheme is employed in this IC, which means tiny external components can be used. Specifically, 1mm tall inductor and 0.22µF output capacitor for a typical application is sufficient. Additionally, the Schottky diode in boost circuit is integrated on this chip. AP3019A also provides a disable pin to ease its use for different systems. The output over-voltage protection is implemented in AP3019A. When any LED is broken or in other abnormal conditions, the output voltage will be clamped. The AP3019A is available in standard SOT-23-6 and TSOT-23-6 packages. Features Inherently Uniform LED Current High Efficiency up to 84% No Need for External Schottky Diode Output Over-voltage Protection (OVP) Fixed 1.2MHz Switching Frequency Uses Tiny 1mm Tall Inductor Requires Only 0.22µF Output Capacitor Applications Cellular Phones Digital Cameras LCD modules GPS Receivers PDAs, Handheld Computers SOT-23-6 TSOT-23-6 Figure 1. Package Types of AP3019A May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited 1 WHITE LED STEP-UP CONVERTER Pin Configuration K/KT Package (SOT-23-6/TSOT-23-6) Pin 1 Dot by Marking SW 1 GND 2 FB 3 6 VIN 5 VOUT 4 CTR...