Dual Interface for
Flat Panel Displays
a
AD9887
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Analog Interface
140 MSPS Maximum Conversion Rate
330 MHz Analog Bandwidth
0.5 V to 1.0 V Analog Input Range
500 ps p-p PLL Clock Jitter at 140 MSPS
3.3 V Power Supply
Full Sync Processing
Midscale Clamp
ANALOG
INTERFACE
REF
REFOUT
REFIN
R
OUTA
8
8
8
8
8
R
CLAMP
A/D
A/D
A/D
AIN
R
OUTB
G
OUTA
8
8
4:2:2 Output Format Mode
G
AIN
CLAMP
CLAMP
G
OUTB
Digital (DVI 1.0 Compatible) Interface
112 MHz Operation (1 Pixel/Clock Mode)
High Skew Tolerance of One Full Input Clock
Sync Detect for “Hot Plugging”
B
8
8
OUTA
B
B
AIN
OUTB
DATACK
HSOUT
2
APPLICATIONS
HSYNC
VSYNC
COAST
CLAMP
CKINV
CKEXT
FILT
RGB Graphics Processing
LCD Monitors and Projectors
Plasma Display Panels
Scan Converters
SYNC
8
VSOUT
PROCESSING
AND CLOCK
GENERATION
R
OUTA
SOGOUT
8
8
8
8
8
2
R
OUTB
S
CDT
G
OUTA
Micro Displays
M
U
X
E
S
Digital TV
G
OUTB
SCL
SDA
B
OUTA
SERIAL REGISTER
AND
B
OUTB
A
A
1
0
POWER MANAGEMENT
GENERAL DESCRIPTION
DATACK
HSOUT
VSOUT
SOGOUT
DE
The AD9887 offers designers the flexibility of a dual analog and
digital interface for flat panel displays (FPDs) on a single chip.
Both interfaces are optimized for excellent image quality supporting
display resolutions up to SXGA (1280 × 1024 at 75 Hz). Either the
analog or the digital interface can be selected by the user.
DIGITAL
INTERFACE
R
8
8
OUTA
8
8
R
OUTB
Rx0+
Rx0–
Rx1+
Rx1–
Rx2+
Rx2–
RxC+
RxC–
G
8
8
OUTA
Analog Interface
G
For ease of design and to minimize cost, the AD9887 is a fully
integrated interface solution for FPDs. The AD9887 includes an
analog interface with a 140 MHz triple ADC with internal 1.25 V
reference, PLL to generate a pixel clock from HSYNC, program-
mable gain, offset, and clamp control. The user provides only a
3.3 V power supply, analog input, and HSYNC. Three-state
CMOS outputs may be powered from 2.5 V to 3.3 V.
OUTB
B
DVI
RECEIVER
8
8
OUTA
8
B
OUTB
2
DATACK
DE
HSYNC
VSYNC
R
TERM
The AD9887’s on-chip PLL generates a pixel clock from HSYNC.
Pixel clock output frequencies range from 12 MHz to 140 MHz.
PLL clock jitter is 500 ps p-p typical at 140 MSPS. When a
COAST signal is presented, the PLL maintains its output fre-
quency in the absence of HSYNC. A sampling phase adjustment is
provided. Data, HSYNC and Clock output phase relationships are
maintained. The PLL can be disabled and an external clock input
provided as the pixel clock. The AD9887 also offers full sync pro-
cessing for composite sync and sync-on-green applications.
AD9887
Digital Interface
The AD9887 contains a Digital Video Interface (DVI 1.0) compat-
ible receiver. This receiver supports displays ranging from VGA
to SXGA (25 MHz to 112 MHz). The receiver operates with
true color (24-bit) panels in 1 or 2 pixel(s)/clock mode, and also
features an intrapair skew tolerance up to one full clock cycle.
A clamp signal is generated internally or may be provided by
the user through the CLAMP input pin. The analog interface
is fully programmable via a 2-wire serial interface.
Fabricated in an advanced CMOS process, the AD9887 is pro-
vided in a 160-lead MQFP surface mount plastic package and is
specified over the 0°C to 70°C temperature range.
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, norforanyinfringementsofpatentsorotherrightsofthirdpartiesthat
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
Fax: 781/326-8703
www.analog.com
© Analog Devices, Inc., 2001