REV. B
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
a
CMOS Monolithic 256318
Color Palette RAM-DAC
ADV476
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 Fax: 617/326-8703
FUNCTIONAL BLOCK DIAGRAM
FEATURES
Personal System/2* and VGA* Compatible
Plug-in Replacement for INMOS 171/176
66 MHz Pipelined Operation
Three 6-Bit D/A Converters
256318 Color Palette RAM
RS-343A/RS-170 Compatible Outputs
Blank on All Three Channels
Standard MPU Interface
Asynchronous Access to All Internal Registers
15 V CMOS Monolithic Construction
Low Power Dissipation
Standard 28-Pin, 0.6" DIP and 44-Pin PLCC
APPLICATIONS
High Resolution Color Graphics
CAE/CAD/CAM Applications
Image Processing
Instrumentation
Desktop Publishing
AVAILABLE CLOCK RATES
66 MHz
50 MHz
35 MHz
GENERAL DESCRIPTION
The ADV476 (ADV
®
) is a pin compatible and software compat-
ible RAM-DAC designed specifically for VGA and Personal
System/2 color graphics.
The ADV476 is a complete analog output RAM-DAC on a
single monolithic chip. The part contains a 256318 color
lookup table, a pixel mask register as well as a triple 6-bit video
D/A converter. The ADV476 is capable of simultaneously dis-
playing up to 256 colors, from a total color palette of 262,144
addressable colors.
The on-chip asynchronous MPU bus allows access to the color
lookup table without affecting the input video data via the pixel
port. The pixel read mask register provides a convenient way of
altering the displayed colors without updating the color lookup
table. The ADV476 is capable of generating RGB video output
signals which are compatible with RS-343A and RS-170 video
standards, without requiring external buffering.
The ADV476 is fabricated in a +5 V CMOS process. Its mono-
lithic CMOS construction ensures greater functionality with low
power dissipation and small board area. The part is packaged in
a 0.6", 28-pin DIP and a 44-pin PLCC.
PRODUCT HIGHLIGHTS
1. Standard video refresh rates, 35 MHz, 50 MHz and
66 MHz.
2. Fully compatible with VGA and Personal System/2 color
graphics.
3. Guaranteed monotonic. Integral and differential linearity
guaranteed to be a maximum of ±1 LSB.
4. Low glitch energy, 75 pV secs.
*Personal System/2 and VGA are trademarks of International Business
Machines Corp.
ADV is a registered trademark of Analog Devices, Inc.