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FEATURES
Personal System/2* Compatible
80 MHz Pipelined Operation
Triple 8-Bit (6-Bit) D/A Converters
256 ؋ 24(18) Color Palette RAM
15 ؋ 24(18) Overlay Registers
RS-343A/RS-170 Compatible Outputs
Sync on All Three Channels
Programmable Pedestal (0 or 7.5 IRE)
External Voltage or Current Reference
Standard MPU Interface
+5 V CMOS Monolithic Construction
44-Pin PLCC Package
Power Dissipation: 800 mW
CMOS 80 MHz Monolithic 256 ؋ 24(18)
Color Palette RAM-DACs
ADV478/ADV471
FUNCTIONAL BLOCK DIAGRAM
OBS
APPLICATIONS
High Resolution Color Graphics
CAE/CAD/CAM Applications
Image Processing
Instrumentation
Desktop Publishing
AVAILABLE CLOCK RATES
80 MHz
66 MHz
50 MHz
35 MHz
OLE
GENERAL DESCRIPTION
The ADV478 (ADV®) and ADV471 are pin compatible and
software compatible RAM-DACs designed specifically for
Personal System/2 compatible color graphics.
The ADV478 has a 256 × 24 color lookup table with triple 8-bit
video D/A converters. It may be configured for either 6 bits or
8 bits per color operation. The ADV471 has a 256 × 18 color
lookup table with triple 6-bit video D/A converters.
Options on both parts include a programmable pedestal (0 or
7.5 IRE) and use of an external voltage or current reference.
TE
Fifteen overlay registers provide for overlaying cursors, grids,
menus, EGA emulation, etc. Also supported is a pixel read
mask register and sync generation on all three channels.
The ADV478 and ADV471 generate RS-343A compatible
video signals into a doubly terminated 75 Ω load, and RS-170
compatible video signals into a singly terminated 75 Ω load,
without requiring external buffering. Differential and integral
linearity errors are guaranteed to be a maximum of ± 1 LSB for
the ADV478 and ± 1/4 LSB for the ADV471 over the full temperature range.
ADV is a registered trademark of Analog Devices, Inc.
*Personal System/2 is a trademark of International Business Machines Corp.
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
