CP2126 Datasheet | CHIP

Product Brief DC/DC Series CP2126_PB_ ENG _Rev1.0 March,2004 Step-Up White-LED Driver .. OVERVIEW The CP2126 is a step-up DC/DC converter specifically designed to drive white LEDs with a constant current. The device can drive two, three or four white LEDs in series from a Li-Ion cell. Series connection of LEDs provides identical LED currents resulting in uniform brightness. The CP2126 switches at 900KHz， allowing the use of tiny ponents. The external capacitor can be as small as 0.22u F, saving space and cost versus alternative solutions. A low 95m V feedback voltage minimizes power loss in the current setting resistor for better efficiency. SOT23-5L -40℃～85℃ Features Inherently matched LED current High efficiency: 85% typical Drives up to four LEDs from a 3.2V supply 20V stable bipolar switch Fast 900KHz switching frequency Uses tiny 1mm tall inductors Requires only 0.22u F output capacitor Operating Industrial temperature range: -40℃ ~ 85℃ SOT23-5L package 95m V + + RC CC VREF 1.25V A1 - A2 Q1 + + Ramp Generator Power Down 900KHz Oscillator A3 - 0.2 Ohm SHDN 4 Copyright ©2004 Chiphomer Technology Limited Page 1 of 1 Product Brief DC/DC Series CP2126_PB_ ENG _Rev1.0 March,2004 Step-Up White-LED Driver .. APPLICATIONS Cellular phones Digital Cameras MP3 Players PDAs、Handheld puters GPS Receivers TYPICAL APPLICATION L1 22u H D1 Vout VIN C1 1u...