BUF08821

Analog

(9Vto20V)

Digital

(2.0Vto5.5V)

BKSEL

V

COM

OUT7

OUT8

OUT1

OUT2

A0

SCL

SDA

ControlIF

BUF08821

1

BUF08821

www.ti.com

SBOS438D

– AUGUST 2008 – REVISED JULY 2011

Programmable Gamma-Voltage Generator and

VCOM Calibrator with Integrated Two-Bank Memory

Check for Samples: BUF08821

1

FEATURES

DESCRIPTION

The BUF08821 offers eight programmable gamma

234

•

10-BIT RESOLUTION

channels plus one programmable VCOM channel.

•

8-CHANNEL P-GAMMA

The final gamma and VCOM values can be stored in

•

1-CHANNEL P-VCOM

the

on-chip,

nonvolatile

memory.

To

allow

for

•

16x REWRITABLE NONVOLATILE MEMORY

programming errors or liquid crystal display (LCD)

•

TWO INDEPENDENT PIN-SELECTABLE

panel rework, the BUF08821 supports up to 16 write

MEMORY BANKS

operations to the on-chip memory.

•

RAIL-TO-RAIL OUTPUT:

The BUF08821 has two separate memory banks,

300mV Minimum Swing-to-Rail (10mA)

allowing simultaneous storage of two different gamma

> 300mA Maximum IOUT

curves to facilitate switching between gamma curves.

•

LOW SUPPLY CURRENT

All gamma and VCOM channels offer a rail-to-rail

•

SUPPLY VOLTAGE: 9V to 20V

output that typically swings to within 150mV of either

•

DIGITAL SUPPLY: 2V to 5.5V

supply rail with a 10mA load. All channels are

•

I2C

™ INTERFACE: Supports 400kHz and

programmed using an I2C interface that supports

3.4MHz Clock Frequency

standard operations up to 400kHz and high-speed

data transfers up to 3.4MHz.

APPLICATIONS

The

BUF08821

is

manufactured

using

Texas

•

TFT-LCD REFERENCE DRIVERS

Instruments

’ proprietary, state-of-the-art, high-voltage

CMOS process. This process offers very dense logic

and HIGH supply voltage operation of up to 20V. The

BUF08821 is offered in a HTSSOP-20 PowerPAD

™

package. It is specified from

–40°C to +85°C.

RELATED PRODUCTS

FEATURES

PRODUCT

22-Channel Gamma Correction Buffer

BUF22821

16-Channel Gamma Correction Buffer

BUF16821

12-Channel Gamma Correction Buffer

BUF12800

18-/20-Channel Programmable Buffer, 10-Bit, VCOM

BUF20800

18-/20-Channel Programmable Buffer with Memory

BUF20820

Programmable VCOM Driver

BUF01900

18V Supply, Traditional Gamma Buffers

BUF11704

22V Supply, Traditional Gamma Buffers

BUF11705

1

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.

2

PowerPAD is a trademark of Texas Instruments, Incorporated.

3

I2C is a trademark of NXP Semiconductors.

4

All other trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright

© 2008–2011, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.