19-4718; Rev 4; 2/11
KIT
ATION
EVALU
E
BL
AVAILA
10-Bit, Programmable Gamma Reference
Systems with MTP for TFT LCDs
General Description
The MAX9672/MAX9673/MAX9674 output 12/14/16 volt-
age references for gamma correction in TFT LCDs and
one voltage reference for VCOM. Each gamma refer-
ence voltage has its own 10-bit DAC and buffer to
ensure a stable voltage. The VCOM reference voltage
has its own 10-bit DAC and an amplifier to ensure a sta-
ble voltage when critical levels and patterns are dis-
played. The MAX9672/MAX9673/MAX9674 feature
integrated multiple-time programmable (MTP) memory to
store gamma and VCOM values on the chip, eliminating
the need for external EEPROM. The MAX9672/
MAX9673/MAX9674 support up to 300 write operations
to the on-chip nonvolatile memory.
The gamma outputs can drive 200mA peak transient
current and settle within 1µs. The VCOM output can
provide 600mA peak transient current and also settles
within 1µs. The analog supply voltage range extends
from 9V to 20V, and the digital supply voltage range
extends from 2.7V to 3.6V.
Gamma values and the VCOM value are programmed
into registers through the I
2
C interface.
o
DAC Reference Input
o
12/14/16-Channel Gamma Correction, 10-Bit
Resolution
o
VCOM Driver
o
Integrated MTP Memory
o
Programmable VCOM Limits
o
200mA Peak Current on Gamma Channels
o
600mA Peak Current on VCOM Channel
Features
MAX9672/MAX9673/MAX9674
Ordering Information
PART
MAX9672ETI+
MAX9673ETI+
MAX9674ETI+
GAMMA
CHANNELS
12
14
16
PIN-PACKAGE
28 TQFN-EP
*
28 TQFN-EP
*
28 TQFN-EP
*
+Denotes
a lead(Pb)-free/RoHS-compliant package.
*EP
= Exposed pad.
Note:
All devices are specified over the -40°C to +85°C temper-
ature range.
Applications
TFT LCDs
10
Functional Diagram
REF
AVDD
10
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
10-BIT
DAC
GMA1
Pin Configuration
GMA8
GMA7
GMA6
GMA5
GMA4
AVDD
REF
10
10
GMA2
10
10
GMA3
TOP VIEW
10
10
GMA4
10
10
GMA5
21
GMA9 22
GMA10 23
GMA11 24
GMA12 25
GMA13* 26
GMA14* 27
GMA15** 28
1
GMA16**
20
19
18
17
16
15
14
13
GMA3
GMA2
GMA1
GND
AVDD
AVDD_AMP
VCOM_FB
MTP
MEMORY
I
2
C
REGISTERS
10
10
GMA6
10
10
GMA7
10
10
GMA8
MAX9672
MAX9673
MAX9674
+
EP
†
12
11
10
9
8
10
DAC
REGISTERS
10
GMA9
10
10
GMA10
10
10
GMA11
10
10
GMA12
10
10
GMA13*
10
10
GMA14*
2
SCL
3
SDA
4
A0
5
DVDD
6
AGND_AMP
7
10
10
VCOM
GMA15**
10
10
GMA16**
AVDD_AMP
VCOM
AGND_AMP
VCOM_FB
10
10
THIN QFN
(5mm
×
5mm)
†
EP = EXPOSED PAD, CONNECT EP TO GROUND PLANE.
*N.C. FOR THE MAX9672
**N.C. FOR THE MAX9672 AND THE MAX9673
DVDD
SDA
SCL
A0
GND
I
2
C
INTERFACE
MAX9672
MAX9673
MAX9674
*NOT AVAILABLE FOR THE MAX9672
**NOT AVAILABLE FOR THE MAX9672 AND THE MAX9673
GND
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
10-Bit, Programmable Gamma Reference
Systems with MTP for TFT LCDs
MAX9672/MAX9673/MAX9674
ABSOLUTE MAXIMUM RATINGS
Supply Voltages
AVDD, REF to GND ............................................-0.3V to +22V
AVDD_AMP to AGND_AMP................................-0.3V to +22V
AVDD to AVDD_AMP.........................................-0.3V to +0.3V
DVDD to GND.......................................................-0.3V to +4V
AGND_AMP to GND..........................................-0.1V to +0.1V
Outputs
GMA1–GMA16 ...................................-0.3V to (V
AVDD
+ 0.3V)
VCOM .........................................-0.3V to (V
AVDD_AMP
+ 0.3V)
Inputs
SDA, SCL..............................................................-0.3V to +6V
VCOM_FB...................................-0.3V to (V
AVDD_AMP
+ 0.3V)
SDA, SCL..........................................................................±20mA
GMA1–GMA16................................................................±200mA
VCOM .............................................................................±600mA
Continuous Power Dissipation (T
A
= +70°C)
28-Pin TQFN-EP (derate 28.6mW/°C
above +70°C) ........................................................2285.7mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow) ...................................... +260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
AVDD
= 18V, V
AVDD_AMP
= V
REF
= 18V, V
DVDD
= 3.3V, V
GND
= V
AGND_AMP
= 0, VCOM = VCOM_FB, no load, T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
SUPPLIES
Analog Supply Voltage Range
Analog Supply Voltage Range for
Programming MTP
Digital Supply Voltage Range
Analog Quiescent Current
VCOM Quiescent Current
Digital Quiescent Current
Thermal Shutdown
Thermal-Shutdown Hysteresis
Undervoltage Lockout Threshold
REF Input Resistance
VCOM OUTPUT (VCOM)
Resolution
Integral Nonlinearity Error
Differential Nonlinearity Error
Total Output Error
Total Output-Error Drift
Output-Voltage Low
RES
INL
DNL
V
ERR
∆V
ERR
V
OUT
Code = 512, V
AVDD_AMP
= 9V and 20V, T
A
= +25°C
Code = 512
T
A
= +25°C, sinking 100mA
-40
15
0.4
0.85
10
0.125
0.125
1
1
+40
Bits
LSB
LSB
mV
µV/°C
V
UVLO
DVDD undervoltage lockout voltage
threshold
V
AVDD
,
V
AVDD_AMP
V
AVDD_MTP
V
DVDD
I
AVDD
I
AVDD_AMP
I
DVDD
During a register mode load event
No SCL or SDA transitions
Guaranteed by total output error
9
15
2.7
20
2.7
400
260
+160
15
2.3
384
2.6
600
20
20
3.6
35
5.6
V
V
V
mA
mA
µA
°C
°C
V
kΩ
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
10-Bit, Programmable Gamma Reference
Systems with MTP for TFT LCDs
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= 18V, V
AVDD_AMP
= V
REF
= 18V, V
DVDD
= 3.3V, V
GND
= V
AGND_AMP
= 0, VCOM = VCOM_FB, no load, T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Output-Voltage High
SYMBOL
V
OUT
CONDITIONS
T
A
= +25°C, sourcing 100mA
To AVDD_AMP, f = 60kHz, REF shorted to
V
AVDD_AMP
9V
≤
V
AVDD_AMP
≤
20V
Output Load Regulation
Continuous Output Current
Short-Circuit Current
Slew Rate
SR
LR
I
O
Transient -80mA to +80mA, code = 512
Code = 512 (Note 2)
9V
≤
V
AVDD_AMP
≤
20V
Swing 4V
P-P
at VCOM, 10% to 90%,
R
L
= 10kΩ, C
L
= 50pF (Note 3)
From SCL rising edge for ACK bit after
programming VCOM to 50% voltage
change at output
R
S
= 10kΩ, C
L
= 50pF (Note 3)
RMS noise voltage (10MHz BW)
Guaranteed monotonic
10
0.125
0.125
Code = 512, V
AVDD
= 9V and 20V,
T
A
= +25°C
T
A
= +25°C, sinking 10mA
T
A
= +25°C, sourcing 10mA
To AVDD, f = 60kHz, REF shorted to
AVDD
9V
≤
V
AVDD
≤
20V
Load Regulation
Short-Circuit Current
Output Impedance
Slew Rate
LR
I
SC
Z
O
SR
-12mA to +12mA
Outputs to AVDD or GND
Output resistance when output is disabled
Swing 5V
P-P
at input, 10% to 90%
measurement on output
From SCL rising edge for ACK bit after
programming gamma to 50% voltage
change at output
RMS noise voltage at any output (10MHz
BW)
f = 5MHz, all channels to all channels
60
V
AVDD
- 0.38
-40
0.15
V
AVDD
- 0.25
40
90
0.5
200
84
22
mV/mA
mA
kΩ
V/µs
1
1
+40
0.28
60
MIN
TYP
MAX
UNITS
V
MAX9672/MAX9673/MAX9674
V
AVDD_AMP
V
AVDD_AMP
- 1.1
- 0.6
40
90
±0.1
80
600
100
Power-Supply Rejection Ratio
PSRR
dB
mV/mA
mA
mA
V/µs
Program to Output Delay
Bandwidth
Noise
DAC OUTPUTS (GMA1–GMA16)
Resolution
Integral Nonlinearity Error
Differential Nonlinearity Error
Total Output Error
Output-Voltage Low
Output-Voltage High
t
D
BW
e
N
RES
INL
DNL
V
ERR
V
OUT
V
OUT
0.8
60
375
µs
MHz
µV
Bits
LSB
LSB
mV
V
V
Power-Supply Rejection Ratio
PSRR
dB
Program to Output Delay
t
D
0.8
µs
Noise
Channel-to-Channel Isolation
e
N
CXTLK
375
80
µV
dB
_______________________________________________________________________________________
3
10-Bit, Programmable Gamma Reference
Systems with MTP for TFT LCDs
MAX9672/MAX9673/MAX9674
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= 18V, V
AVDD_AMP
= V
REF
= 18V, V
DVDD
= 3.3V, V
GND
= V
AGND_AMP
= 0, VCOM = VCOM_FB, no load, T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
LOGIC INPUTS (SDA, SCL)
Input High Voltage
Input Low Voltage
Input Leakage Current
Input Capacitance
Power-Down Input Current
SDA Output Low Voltage
Serial-Clock Frequency
Bus Free Time Between STOP
and START Conditions
Hold Time (REPEATED) START
Condition
SCL Pulse-Width Low
SCL Pulse-Width High
Setup Time for a REPEATED
START Condition
Data Hold Time
Data Setup Time
SDA and SCL Receiving Rise
Time
SDA and SCL Receiving Fall
Time
SDA Transmitting Fall
Time
Setup Time for STOP Condition
Bus Capacitance
Pulse Width of Suppressed Spike
I
IN
V
OL
f
SCL
t
BUF
t
HD,STA
t
LOW
t
HIGH
t
SU,STA
t
HD,DAT
t
SU,DAT
t
R
t
F
t
F,TX
t
SU,STO
C
B
t
SP
0
(Note 4)
(Note 4)
(Note 4)
V
DVDD
= 0V, V
IN
= 2V
I
SINK
= 6mA
0
1.3
0.6
1.3
0.6
0.6
0
100
20 +
0.1C
B
20 +
0.1C
B
20 +
0.1C
B
0.6
400
50
300
300
250
900
-10
V
IH
V
IL
I
IH
, I
IL
V
IN
= 0V or V
DVDD
-1
+0.01
5
+10
0.4
400
0.7 x
V
DVDD
0.3 x
V
DVDD
+1
V
V
µA
pF
µA
V
kHz
µs
µs
µs
µs
µs
ns
ns
ns
ns
ns
µs
pF
ns
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
I
2
C TIMING CHARACTERISTICS (Figure 1)
Note 1:
Note 2:
Note 3:
Note 4:
All devices are 100% production tested at T
A
= +25°C. All temperature limits are guaranteed by design.
Thermal pad attached to multilayered board. Exceeding this limit may cause the thermal shutdown to trip.
Measured with the VCOM amplifier configured as an inverting unity-gain amplifier (R
S
= R
F
= 1kΩ).
C
B
is in pF.
4
_______________________________________________________________________________________
10-Bit, Programmable Gamma Reference
Systems with MTP for TFT LCDs
Typical Operating Characteristics
(V
AVDD
= V
AVDD_AMP
= V
REF
= 18V, V
DVDD
= 3.3V, V
GND
= V
AGND_AMP
= 0, no load, unless otherwise noted. Typical values are at
T
A
= +25°C.)
OUTPUT OFFSET-VOLTAGE
DISTRIBUTION
MAX9672/73/74 toc01
MAX9672/MAX9673/MAX9674
GAMMA LOAD REGULATION
15
LOAD REGULATION (mV)
10
5
0
-5
-10
-15
-20
MAX9672/73/74 toc02
30
25
20
N (%)
15
10
5
0
-40 -30 -20 -10
0
10
20
30
40
OUTPUT OFFSET (mV)
20
-20
-15
-10
-5
0
5
10
15
20
LOAD CURRENT (mA)
VCOM LOAD REGULATION
MAX9672/73/74 toc03
DNL
GAMMA
0.20
0.15
0.10
DNL (LSB)
0.05
0
-0.05
-0.10
-0.15
-0.20
MAX9672/73/74 toc04
60
40
LOAD REGULATION (mV)
20
0
-20
-40
-60
-150
-100
-50
0
50
100
0.25
-0.25
150
0
128 256 384 512 640 768 896 1024
CODE (UNITS)
LOAD CURRENT (mA)
DNL
VCOM
MAX9672/73/74 toc05
0.20
0.15
0.10
DNL (LSB)
0.05
0
-0.05
-0.10
-0.15
-0.20
-0.25
0
0.20
0.15
0.10
INL (LSB)
0.05
0
-0.05
-0.10
-0.15
-0.20
V
REF
= 10V
128 256 384 512 640 768 896 1024
CODE (UNITS)
-0.25
0
128 256 384 512 640 768 896 1024
CODE (UNITS)
_______________________________________________________________________________________
MAX9672 toc06
0.25
GAMMA
INL
0.25
5