ADD8754: LCD Panel Power, VCOM,and Gate Modulation
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 step-up switching regulator frequency can be chosen, allowing easy filtering and low noise operation. It achieves 93% efficiency and features soft start to limit the inrush current at startup.
The internal voltage regulator operates with an input voltage range of 3 V to 5.5 V and delivers a load current of up to 350 mA. Three selectable output voltages are available: 2.5 V, 2.85 V, and 3.3 V.
The proprietary VCOM amplifier can deliver a peak output current of 300 mA and is specifically designed to drive TFT panel loads.
The gate pulse modulator allows shaping of the TFT gate high voltage to improve image quality. The integrated switches provide the ability to independently control the delay and slope for the gate drive voltage.
The ADD8754 is offered in a 24-lead, Pb-free LFCSP package and is specified over the industrial temperature range of -40 to +85°C.
ADD8754 特点
- 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
- 3 V to 5.5 V Input
- Undervoltage Lockout
- Thermal Shutdown
- 24-lead, Pb-free LFCSP Package
ADD8754 功能框图
ADD8754 技术指标
| -3dB Bandwidth | 1.95MHz | Vcc-Vee Supply (V) | 8 to 18 |
| Slew Rate | 105V/us | Iq per Amplifier | n/a |
| Vos | 19mV | # OpAmps per Pkg | 1 |
| Ib | 50nA | Operating Temp Range | -40 to +85 |
| Input Noise (nV/rtHz) | n/a | Packages | CSP |