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Functional Description
The Averlogic AL422 is a video frame memory used to buffer audio/video/graphic
data for digital processing, timing correction, or
format conversion. It is manufactured with
state-of-the-art embedded DRAM technology for
applications in TVs, VCRs, scan converters, and
digital video systems.
The AL422 consists of 3Mbits of DRAM, and is
configured as 393,216 words x 8 bit FIFO (first in
first out). The high speed and low power consumption
are achieved by using 0.35 micron process technology
with embedded EDO dynamic memory. The interface is
very user-friendly since all complicated DRAM
operations are already managed by the internal DRAM
controller.
Current sources of similar memory (field memory) in
the market provide limited memory size which is only
enough for holding a TV field, but not enough for a
whole PC video frame which normally contains 640x480
or 720x480 bytes. The AverLogic AL422 provides 50%
more memory to support high resolution for digital PC
graphic or video applications. The 50% increase in
speed also expands the range of applications.
The AL422 can accept either 3.3V or 5V power with
slightly different external configuration. The
internal voltage regulator can convert 5V power to
3.3V for the embedded DRAM and logic circuitry when 5V
power is applied to VDD pin (#10) only and leave the
DEC pin (#19) decoupled by a capacitor of 2.2uF to
ground. The regulator can also be bypassed when 3.3V
power is applied to both VDD and DEC pins. In either
case the AL422 is 5V or 3.3V I/O tolerant. The 3.3V
configuration consumes less power and is free from
noise interference from the voltage regulator so may
be more ideal for high-speed applications.
Please note that using the AL422B with 5V
configuration can directly replace the previous
AL422V5; using it with 3.3V configuration can directly
replace the previous AL422V3. No additional
modification is required.
For more information about the AL422 or other
AverLogic products, please contact your local
authorized distributor, representative, visit our
website, or contact us directly. |
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Applications
*Multimedia systems
*Video capture systems
*Video editing systems
*Scan rate converters
*TV¡¦s picture in picture feature
*Anti-skip CD players
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Reference Kit: |
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*384K (393,216) x 8 bits
FIFO organization
*Supports VGA and CCIR resolutions
*Independent read/write operations (different I/O data
rates acceptable)
*High speed asynchronous serial access
*Read/write cycle time: 20 ns
*Access time: 15 ns
*Output enable control (data skipping)
*5V or 3.3V power supply
*Standard 28-pin SOP package
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