BUF08800
SBOS380A − FEBRUARY 2007 − REVISED MAY 2007
Programmable Reference Generator
and 400mA V
COM
Driver
FEATURES
D
10-BIT RESOLUTION
D
7- OR 8-CHANNEL GAMMA CORRECTION
D
INTEGRATED V
COM
DRIVER:
D
D
D
D
D
D
D
400mA PEAK CURRENT
DIGITAL GATE VOLTAGE ADJUSTMENT
CIRCUITS
RAIL-TO-RAIL OUTPUT
LOW SUPPLY CURRENT: 1mA/ch
SUPPLY VOLTAGE: 7V to 22V
DIGITAL SUPPLY: 2.0V to 5.5V
INDUSTRY-STANDARD, TWO-WIRE
INTERFACE
HIGH ESD RATING: 4kV HBM
DESCRIPTION
The BUF08800 reference generator offers eight program-
mable reference channels that can be used depending on
the application needs. For example, all eight channels can
be used for gamma correction, or some as gamma
references and some to digitally adjust the gate voltages
or V
COM
.
All gamma/V
COM
channels swing to within 100mV of the
positive or negative supply rail with a 10mA load. All
channels are programmed using a standard two-wire
interface that supports standard operation up to 400kHz
and also high-speed data transfer up to 3.4MHz.
The integrated V
COM
driver features up to 400mA peak
current drive. V
COM
voltage compensation at different
locations on the LCD panel can be accomplished using the
negative input of the integrated V
COM
op amp.
The Gate High and Low voltages can differ because of
changes in panel size or technology. The BUF08800
supports digital adjustment circuits for the gate voltages.
This feature enables the adjustment of gate voltages
through software without changing hardware, thus
reducing development time and risk.
The BUF08800 is manufactured using Texas Instruments’
proprietary, state-of-the-art, high-voltage CMOS process.
This process allows very dense logic as well as high
supply voltage operation of up to 22V.
The BUF08800 is available in a small TSSOP-20
PowerPad package, and is specified from −40°C to
+85°C.
APPLICATIONS
D
TFT-LCD REFERENCE DRIVERS
D
REFERENCE VOLTAGE GENERATORS
V
SD
BUF08800
10−Bit
DAC
250kΩ
V
S
+IN (V
COM
)
V
COM
(OUT 1)
−IN
(V
COM
)
OUT 2
Gamma/V
COM
Register Bank 1
Gamma/V
COM
Register Bank 2
10−Bit
DAC
10−Bit
DAC
OUT 3
10−Bit
DAC
10−Bit
DAC
OUT 7
RELATED PRODUCTS
OUT 8
FEATURES
12-Channel Gamma Correction Buffer
20-Channel Programmable Buffer, 10-Bit, V
COM
16-, 20-Channel Prog. Buffer with Memory
Programmable V
COM
Driver
18V Supply, Traditional Gamma Buffers
22V Supply, Traditional Gamma Buffers
PRODUCT
BUF12800
BUF20800
BUF20820
BUF01900
BUF11704
BUF11705
SDA
SCL
Control IF
A0
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 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
2007, Texas Instruments Incorporated
www.ti.com
BUF08800
www.ti.com
SBOS380A − FEBRUARY 2007 − REVISED MAY 2007
ABSOLUTE MAXIMUM RATINGS
(1)
Supply Voltage, V
S
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +24V
Supply Voltage, V
SD
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6V
Supply Input Terminals, SCL, SDA, AO, LD:
Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5V to +6V
Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±10mA
Output Short-Circuit
(2)
. . . . . . . . . . . . . . . . . . . . . . . . . Continuous
Operating Temperature . . . . . . . . . . . . . . . . . . . . . . −40°C to +95°C
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . −65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +125°C
(1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods
may degrade device reliability. These are stress ratings only, and
functional operation of the device at these or any other conditions
beyond those specified is not supported.
(2) Short-circuit to ground.
This integrated circuit can be damaged by ESD. Texas
Instruments recommends that all integrated circuits be
handled with appropriate precautions. Failure to observe
proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to
complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could
cause the device not to meet its published specifications.
ORDERING INFORMATION
(1)
PRODUCT
BUF08800
PACKAGE-LEAD
HTSSOP-20
PACKAGE
DESIGNATOR
PWP
PACKAGE MARKING
BUF08800
ORDERING NUMBER
BUF08800AIPWPR
(1) For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI web site
at www.ti.com.
PIN CONFIGURATIONS
Top View
BUF08800
HTSSOP
GND
GND
+IN (V
COM
)
−
IN (V
COM
)
V
SD
SCL
SDA
A0
LD
GND (digital)
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
COM
(OUT 1)
V
S
V
S
OUT 2
OUT 3
OUT 4
OUT 5
OUT 6
OUT 7
OUT 8
2
BUF08800
www.ti.com
SBOS380A − FEBRUARY 2007 − REVISED MAY 2007
ELECTRICAL CHARACTERISTICS
Boldface
limits apply over the specified temperature range:
T
A
= −40°C to +85°C.
At T
A
= +25°C, V
S
= +18V, V
SD
= 2.5V, R
L
= 1.5kΩ to GND, and C
L
= 200pF, unless otherwise noted.
BUF08800
PARAMETER
ANALOG
Gamma Buffer Channels
Reset Value
Buffer 2−4 Output Swing: High
Buffer 2−4 Output Swing: Low
Buffer 5−8 Output Swing: High
Buffer 5−8 Output Swing: Low
Continuous Output Current
Output Accuracy
vs Temperature
Integral Nonlinearity
INL
Differential Nonlinearity
DNL
Load Regulation, 10mA
REG
V
COM
Driver/OUT 1
Reset Value
Driver Input Range
Driver Offset
V
COM
/OUT 1 Output Swing: High
V
COM
/OUT 1 Output Swing: Low
V
COM
/OUT 1 Output Swing: High
V
COM
/OUT 1 Output Swing: Low
V
BIAS
Output Impedance
Overall Output Accuracy
vs Temperature
Integral Nonlinearity
INL
Differential Nonlinearity
DNL
Load Regulation, 100mA
REG
Program to Out Delay
t
D
ANALOG POWER SUPPLY
Operating Range
Total Analog Supply Current
Over Temperature
DIGITAL
Logic 1 Input Voltage
Logic 0 Input Voltage
Logic 0 Output Voltage
Input Leakage
Clock Frequency
DIGITAL POWER SUPPLY
Operating Range
Digital Supply Current
(1)
Over Temperature
TEMPERATURE RANGE
Specified Range
Operating Range
Storage Range
Thermal Resistance
(2)
HTSSOP-20
HTSSOP-20
−40
−40
−65
35
20
I
S
Outputs at Reset Values, No Load
CONDITIONS
MIN
TYP
MAX
UNITS
Code = 512
Code = 1023, Sourcing 10mA
Code = 0, Sinking 10mA
Code = 1023, Sourcing 10mA
Code = 0, Sinking 10mA
17.8
17.0
Code 512
Code = 512, I
OUT
= +5mA to −5mA Step
Code = 00, No Load on Pin 2, I
OUT
= 0
I
OUT
= 0mA
Referred to Pin 2, Code = 512
Pin 9, Code = 1023, Sourcing 10mA
Pin 9, Code = 0, Sinking 10mA
Pin 9, Code = 1023, Sourcing 400mA
Pin 9, Code = 0, Sinking 400mA
Pin 2
Pin 20
Code = 512
Pin 20
Pin 20
Pin 20, Code = 512, I
OUT
= +200mA to −200mA Step
All Channels
9
17.85
0.7
17.2
0.2
30
±10
±20
0.3
0.3
0.5
9
1
0.25
±50
1
2.5
1.5
V
V
V
V
V
mA
mV
µV/°C
Bits
Bits
mV/mA
V
V
mV
V
V
V
V
kΩ
mV
µV/°C
Bits
Bits
mV/mA
µs
V
mA
mA
V
V
V
µA
kHz
MHz
V
µA
µA
0.7
17.8
14
1
17.9
0.7
14.6
3.5
250
±20
±25
0.3
0.3
0.5
5
17.9
±5
1
4
±50
1
2.5
1.5
7
7
22
15
15
V
IH
V
IL
V
OL
0.7
×
V
SD
I
SINK
= 3mA
Standard/Fast Mode
High-Speed Mode
0.15
±0.01
0.3
×
V
SD
0.4
±10
400
3.4
5.5
25
100
+85
+95
+150
50
V
SD
I
SD
Outputs at Reset Values, No Load, Two-Wire Bus
Inactive
2.0
Junction Temperature < +125°C
°C
°C
°C
°C/W
°C/W
q
JA
q
JC
(1) See typical characteristic curve
Digital Supply Current vs Two-Wire Bus Activity.
(2) Thermal pad attached to printed circuit board (PCB), 0lfm airflow, and 76mm
×
76mm copper area.
3
BUF08800
www.ti.com
SBOS380A − FEBRUARY 2007 − REVISED MAY 2007
TYPICAL CHARACTERISTICS
At T
A
= +25°C, V
S
= +18V, V
SD
= 2.5V, R
L
= 1.5kΩ to GND, and C
L
= 200pF, unless otherwise noted.
ANALOG SUPPLY CURRENT vs TEMPERATURE
8
7
6
5
I
Q
(mA)
I
Q
(µA)
4
3
2
1
0
−50
−25
0
25
50
75
100
125
Temperature (_ C)
0
−50
5
10
15
20
DIGITAL SUPPLY CURRENT vs TEMPERATURE
−25
0
25
50
75
100
125
Temperature (
_
C)
Figure 1
CHANNEL 2 FULL−SCALE OUTPUT SWING
Figure 2
CHANNEL 8 FULL−SCALE OUTPUT SWING
5V/div
1µs/div
5V/div
1µs/div
Figure 3
Figure 4
V
COM
CHANNEL FULL−SCALE OUTPUT SWING
DIFFERENTIAL NONLINEARITY ERROR vs INPUT CODE
1.0
0.8
0.6
DNL Error (LSB)
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1.0
Limited by Range
of Voltage Buffer
0
128
256
384
512
640
768
896
1024
V
COM
OUT 1, OUT 2
(5 units shown)
5V/div
5µs/div
Input Code
Figure 5
4
Figure 6
BUF08800
www.ti.com
SBOS380A − FEBRUARY 2007 − REVISED MAY 2007
TYPICAL CHARACTERISTICS (continued)
At T
A
= +25°C, V
S
= +18V, V
SD
= 2.5V, R
L
= 1.5kΩ to GND, and C
L
= 200pF, unless otherwise noted.
DIFFERENTIAL NONLINEARITY ERROR vs INPUT CODE
1.0
0.8
0.6
DNL Error (LSB)
INL Error (LSB)
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1.0
0
128
256
Limited by Range of Voltage Buffer
384
512
640
768
896
1024
OUT 8 (4 units shown)
1.0
0.8
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1.0
0
INTEGRAL NONLINEARITY ERROR vs INPUT CODE
V
COM
OUT 1, OUT 2 (5 units shown)
Limited by Range of Voltage Buffer
128
256
384
512
640
768
896
1024
Input Code
Input Code
Figure 7
INTEGRAL NONLINEARITY ERROR vs INPUT CODE
1.0
0.8
0.6
INL Error (LSB)
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1.0
0
128
256
Limited by Range of Voltage Buffer
384
512
640
768
896
OUT 8 (4 units shown)
Figure 8
1024
Input Code
Figure 9
5
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