DC/DC Converter Powers TFT LCDs

Providing a regulated supply voltage for active-matrix TFT LCDs, the MAX8740 step-up dc/dc converter teams current-mode, fixed-frequency, and PWM circuitry with an n-channel power MOSFET. Operating frequencies of 640 kHz or 1.2 MHz are selectable via a logic input pin, and a compensation pin is available for adjusting loop dynamics. The 30V MOSFET can generate output voltages up to 28V from an input voltage between 2.6V and 5.5V. Additionally, a soft-start function slowly ramps the input current and is programmed with an external capacitor. In a 10-pin TDFN package, prices start at $3.14 each/1,000.MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.