ADD8702

Features:

Programmable 12-Channel Gamma Reference Generator
Mask Programmable Adjustable VCOM Buffer
Upper/Lower Outputs Swing to VDD/GND
Continuous Output Current: 10 mA
V_COM Peak Output Current: 250 mA
Outputs with Fast Settling Time for Load Change
Output Pins Are Compatible with ADD8701
Single-Supply Operation: 7 V to 16 V
Supply Current: 15 mA Max


Application

TFT LCD Panels


Pinout




Specifications

Supply Voltage (V_S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 V
Storage Temperature Range  . . . . . . . . . . . . .65°C to +150°C
Operating Temperature Range  . . . . . . . . . . . . 40°C to +85°C
Junction Temperature Range  . . . . . . . . . . . . .65°C to +150°C
Lead Temperature Range (Soldering, 60 sec.)  . . . . . . . . 300°C
ESD Tolerance (HBM)  . . . . . . . . . . . . . . . . . . . . . . .     ±1,000 V


Description

The ADD8702 is a low cost, mask programmable, 12-channel gamma reference generator, plus an adjustable VCOM driver. This part is designed to provide gamma correction for high resolution TFT LCD panels. The 12 gamma reference levels and VCOM are mask programmable to 0.3% resolution using the on-chip 500 chain resistor string. This reduces component and board costs.

The ADD8702 provides a complete programmed set of gamma voltage references for the LCD source drivers. These references settle quickly to load change. The VCOM output is stable with high capacitive loads and can source or sink 250 mA peak current. The VCOM output level can be adjusted using an external
trim-potentiometer or discrete resistors.