APW7001

APW7001 1X/1.5X/2X Charge Pump White LED Driver for Main and Sub-Displays Features ±1.5% LED Current Matching Powers Main and Sub-Display LEDs High Efficiency Up to 90% Over Li-ion Battery Discharge Output Current Up to 30mA per LED 2.7V to 5.5V Operating Voltage 1x/1.5x/2x Charge Pump Modes Low Shutdown Current: 2µA Maximum Low Input Ripple and EMI Internal Soft-Start Limits Inrush Current Short Circuit Current Limit Thermal Shutdown Protection Output Over-Voltage Protection 16-pin QFN Package Lead Free and Green Devices Available (RoHS Compliant) Applications Cellular Phone White LED Back Light Portable Device PDA, Handheld Computer DSC General Description The APW7001 is a high efficiency charge pump white LED driver; the device drives up to four white LEDs in the main display and up to two white LEDs in the sub-display with regulated constant current for uniform intensity. The supply voltage ranges from 2.7V to 5.5V and it is optimized for a Li-ion battery application. The APW7001 operates in 1x, 1.5x, and 2x charge pump modes and automatically switches the charge pump modes depend on the input voltage to maintain the required power for high power efficiency. The APW7001 provides up to 30mA per LED and allows several methods such as the PWM signals on the ENM pin for main-display dimming and on the ENS pin for sub-display dimming. The two control logic pins, ENM and ENS, allow disabling or enabling the main and sub-displays. The supply...