CP2129

Product Brief Step-Up DC-DC Converter General www.datasheet4u.com Description CP2129 V1.1 DC/DC Series The CP2129 is a step-up DC/DC converter specifically designed for driving white LEDs with a constant current. The device can drive up to 4 white LEDs from a 3V power supply. PWM dimming control is supported to adjust the brightness of the white LEDs. The CP2129 switches at 1.1 MHz allowing the use of tiny components. 250mV feedback voltage minimizes the power loss in the current setting resistor for better efficiency. The CP2129 is equipped with the over voltage protection when the OVP pin connecting to the VOUT, which can make the device keep in safe mode when the LEDs in open state. The CP2129 is available in SOT23-6L package. SOT23-6L -40 85 Features y y y y y y y y Inherently matched LED current High efficiency: 84% (typical) Stable 20V bipolar switches Internal output over-voltage protection (17V typical) Fast 1.1MHz switching frequency Uses tiny 1mm height inductors Shutdown current: <1 A Low profile SOT23-6L package Applications y y y y y Mobile phones Digital still camera MP3 players PDA GPS receivers Pin Configurations CP2129 Top View SOT23-6L Copyright ©2006 Chiphomer Technology Limited 1 Product Brief Step-Up DC-DC Converter Typical Application Circuit www.datasheet4u.com VIN Li-ion Battery CIN 1µF Dimming Control VIN L1 10µH SW D1 CP2129 V1.1 DC/DC Series VOUT COUT 1µF LED1 LED2 LED3 LED4 CP2129 OVP SHDN GND FB R1 12Ω CP2129 Driving 4 LED Contact...