BUF12800
SBOS315 鈭?DECEMBER 2004
REFERENCE VOLTAGE GENERATOR
for LCD GAMMA CORRECTION
FEATURES
D
D
D
D
D
D
D
D
D
D
D
12-CHANNEL GAMMA CORRECTION
10-BIT RESOLUTION
DOUBLE-BUFFERED DAC REGISTERS
INTEGRATED REFERENCE BUFFERS
RAIL-TO-RAIL OUTPUT
LOW SUPPLY CURRENT: 900碌A(chǔ)/ch
SUPPLY VOLTAGE: 7V to 18V
DIGITAL SUPPLY: 2.7V to 5.5V
INDUSTRY-STANDARD TWO-WIRE INTERFACE
鈭?High-Speed Mode: 3.4MHz
HIGH ESD RATING:
鈭?4kV HBM, 1kV CDM, 200V MM
DEMOBOARD AND SOFTWARE AVAILABLE
V
SD
4
V
S
1, 2
REFH
3
APPLICATIONS
D
TFT-LCD REFERENCE DRIVERS
D
REFERENCE VOLTAGE GENERATORS
D
INDUSTRIAL PROCESS CONTROL
DESCRIPTION
The BUF12800 is a programmable voltage reference
generator designed for dynamic gamma correction in
TFT-LCD panels. It provides 12 programmable outputs,
each with 10-bit resolution.
TI鈥檚 new, small geometry, state-of-the-art, analog CMOS
process allows the use of one digital-to-analog converter
(DAC) per channel while still maintaining a very small chip
size. This topology has the advantage of significantly
increased programming speed over existing program-
mable buffers.
Programming of each output occurs through an industry-
standard, two-wire serial interface. Unlike existing
programmable buffers, the BUF12800 offers a high-
speed, two-wire interface mode that allows clock speeds
up to 3.4MHz. The BUF12800 features a double-buffered
DAC register structure that significantly simplifies imple-
mentation of dynamic gamma control. This further reduces
programming time, especially when many channels have
to be updated simultaneously.
Reference pins set the high and low voltages of the output
range. They are internally buffered, which simplifies
design. They may be connected to external resistors to
divide the output range for finer resolution of outputs.
The BUF12800 is available in a TSSOP-24 PowerPAD錚?/div>
package. It is specified from 鈭?0擄C to +85擄C.
BUF12800
13
Out A
14
Out B
15
Out C
16
Out D
17
Out E
DAC Register
DAC Register
18
Out F
19
Out G
20
Out H
21
Out I
22
Out J
23
Out K
24
Out L
BUF12800 RELATED PRODUCTS
FEATURES
11-Channel Gamma Correction Buffer, Int VCOM
6-Channel Gamma Correction Buffer, Int VCOM
6-Channel Gamma Correction Buffer
4-Channel Gamma Correction Buffer, Int VCOM
High-Supply Voltage Gamma Buffers
20-Channel Programmable Buffer, 10-Bit, VCOM
PRODUCT
BUF11702
BUF07703
BUF06703
BUF05703
BUFxx704
BUF20800
6
SDA
Control IF
SCL
5
8
LD
A0
7
10
REFL
9
11, 12
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments
semiconductor products and disclaimers thereto appears at the end of this data sheet.
PowerPAD is a registered trademark of Texas Instruments. All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Products
conform to specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all parameters.
Copyright
錚?/div>
2004, Texas Instruments Incorporated
www.ti.com
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