
BUF08821
Analog
(9Vto20V)
Digital
(2.0Vto5.5V)
BKSEL
V
COM
DACRegisters
OUT7
OUT8
16xNonvolatileMemoryBANK1
16xNonvolatileMemoryBANK0
OUT1
OUT2
A0
SCL
SDA
ControlIF
BUF08821
DACRegisters
1
www.ti.com ................................................................................................................................................. SBOS438C – AUGUST 2008 – REVISED AUGUST 2009
Programmable Gamma-Voltage Generator and
VCOM Calibrator with Integrated Two-Bank Memory
1
FEATURES
DESCRIPTION
234
10-BIT RESOLUTION
The BUF08821 offers eight programmable gamma
channels plus one programmable VCOM channel.
8-CHANNEL P-GAMMA
1-CHANNEL P-VCOM
The final gamma and VCOM values can be stored in
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
programmed using an I2C interface that supports
I2C INTERFACE: Supports 400kHz and
standard operations up to 400kHz and high-speed
3.4MHz Clock Frequency
data transfers up to 3.4MHz.
APPLICATIONS
The
BUF08821
is
manufactured
using
Texas
Instruments’ proprietary, state-of-the-art, high-voltage
TFT-LCD REFERENCE DRIVERS
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
16-Channel Gamma Correction Buffer
12-Channel Gamma Correction Buffer
18-/20-Channel Programmable Buffer, 10-Bit, VCOM
18-/20-Channel Programmable Buffer with Memory
Programmable VCOM Driver
18V Supply, Traditional Gamma Buffers
22V Supply, Traditional Gamma Buffers
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 2008–2009, 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.