Features

• OBSOLETE:  For Information Purposes Only.  Contact Linear Technology for Potential Replacement.
• Complete Solution Under 1.2mm
• Develops Three Outputs from a 3.3V or 5V Supply
• Externally Programmable V_ON 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

Typical Application

Description

OBSOLETE:  For Information Purposes Only.  Contact Linear Technology for Potential Replacement.

The LT1948 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 AV_DD reaching final value to 23V appearing at the V_ON 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 and is available in an 8-lead MSOP package.