ADD8754

www.DataSheet4U.com LCD Panel Power, VCOM, and Gate Modulation ADD8754 FEATURES Step-up switching regulator with 2 A power switch 650 kHz or 1.2 MHz switching frequency Output adjustable to 20 V 350 mA logic voltage regulator Selectable output voltages: 2.5 V, 2.85 V, 3.3 V VCOM amplifier with 300 mA drive Gate pulse modulation circuitry Independently adjustable delay and falling slope General 3 V to 5.5 V input Undervoltage lockout Thermal shutdown 24-lead, Pb-free LFCSP package FUNCTIONAL BLOCK DIAGRAM COMP SS VIN_1 VIN_2 ADD8754 FB FREQ SHDN STEP-UP SWITCHING REGULATOR LX UNDER VOLTAGE LOCKOUT AND THERMAL PROTECTION LOGIC VOLTAGE REGULATOR LDO_OUT ADJ VDD_2 OUT VCOM AMPLIFIER POS NEG APPLICATIONS TFT LCD panels for monitors, TVs, and notebooks VGH GATE PULSE MODULATION 05110-001 VGH_M VDD_1 CE RE VFLK VDPM Figure 1. GENERAL DESCRIPTION The ADD8754 is optimized for use in TFT LCD applications, requiring only external charge pump components to provide all the requirements for panel power, VCOM, and gate modulation. Included in a single chip are a high frequency step-up dc-to-dc switching regulator, logic voltage regulator, VCOM amplifier, and gate pulse modulation circuitry. The step-up dc-to-dc converter provides up to 20 V output and includes a 2 A internal switch. Either a 650 kHz or 1.2 MHz stepup switching regulator frequency can be chosen, allowing easy filtering and low noise operation. It achieves 93% efficiency and features soft start to limit the inr...