LT1948

www.DataSheet4U.com Final Electrical Specifications NOT RECOMMENDED FOR NEW DESIGNS Contact Linear Technology for Potential Replacement LT1948 DC/DC Converter for TFT-LCD Panels August 2000 FEATURES s s s s s s s s s s DESCRIPTIO Complete Solution Under 1.2mm Develops Three Outputs from a 3.3V or 5V Supply Externally Programmable VON Delay Fixed Frequency Low Noise Outputs All Ceramic Capacitors Operates at 3MHz Switching Frequency Fast Transient Response Few External Components Required 2.6V to 6V Input Range Tiny 8-Lead MSOP Package U APPLICATIO S s s s s TFT-LCD Notebook Display Panels TFT-LCD Desktop Monitor Display Panels Digital Cameras Handheld Computers The LT®1948 is a highly integrated multiple output DC/DC converter designed for use in TFT-LCD panels. The device contains two independent switching regulators: the main regulator has an adjustable output voltage with an internal 1.1A switch that can generate a boosted voltage as high as 30V while the second regulator generates 23V at up to 10mA for positive bias. A simple level-shift charge pump off the main switch node generates the negative bias voltage. An external capacitor sets the delay time from AVDD reaching final value to 23V appearing at the VON pin. The 3MHz switching frequency allows the use of tiny low profile chip inductors and capacitors throughout, providing a low noise, low cost total solution with all components under 1.25mm in height. The device operates from an input range of 2.6V to 6V an...