MAX9679 Datasheet, PDF (1/28 Pages) Maxim Integrated Products – 12-Channel, 10-Bit Programmable Gamma and VCOM Reference Voltages

MAX9679
12-Channel, 10-Bit Programmable Gamma
and VCOM Reference Voltages
General Description
The MAX9679 provides multiple programmable
reference voltages for gamma correction in TFT LCDs
and a programmable reference voltage for VCOM
adjustment. All gamma and VCOM reference voltages
have a 10-bit digital-to-analog converter (DAC) and high-
current buffer, which reduces the recovery time of the
output voltages when critical levels and patterns are
displayed. A programmable internal reference sets the
full-scale voltage of the DACs.
Two independent sets of gamma curves and VCOM
codes can be stored in the IC's volatile memory; BKSEL
signal selects between the two sets.
The IC has multiple-time programmable (MTP) memory
to store gamma and VCOM codes on the chip, eliminat-
ing the need for external EEPROM.
TFT LCDs
Applications
Features
S 12 Channels of Programmable Gamma Voltages
with 10-Bit Resolution
S Programmable VCOM Voltage with 10-Bit
Resolution
S Programmable Reference for DACs
S Multiple-Time Programmable Memory to Store
Gamma and VCOM Codes
S Switching Between Two Gamma Curves and
VCOM Voltages
S AVDD1, AVDD2, and AVDD_AMP Supplies to
Reduce Heat
S I²C Interface (1MHz Fast-Mode Plus)
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX9679ETG+
-40NC to +85NC
24 TQFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Simplified Block Diagram
BKSEL
MTP
REG
PROG
REF
I²C
REG
PROG
REF
DAC
REG
PROG
REF
MAX9679
PROG
REF
GAMMA
BANK 1
GAMMA
BANK 1
GAMMA
BANK 1
VCOM1
GAMMA
BANK 2
VCOM1
VCOM2
GAMMA
BANK 2
VCOM1
VCOM2
GAMMA
2:1
MUX
12 DACs
12 GAMMA ¹²
BUFFERS
OUTPUTS
VCOM
2:1
MUX
DAC
VCOM
AMPLIFIER
OUTPUT
I2C
CONTROL
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-5756; Rev 2; 5/13