www.DataSheet4U.com
LCD Panel Power, VCOM, and Gate Modulation
ADD8754
FEATURES
Step-up switching regulator with 2 A p...
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...