AL875A - AverLogic

AL875A
High Speed Triple 8-bit ADC
Applications
−
−
−
−
•
•
•
LCD/PDP Monitors
LCD Projectors
Other Flat Panel Displays
High-end Video/Graphics Processing
•
•
•
•
•
•
•
•
•
•
Description
The AL875 is a high-speed triple 8-bit
monolithic analog-to-digital converter
(ADC) designed for digitizing RGB
graphics/video signal or other applications.
Its 110 MHz conversion rate can support
display resolution up to 1280x1024 at
60Hz.
ADDR1/2
SDA
SCL
High speed 8-bit ADC up to 110MHz encode rate
Support display resolution up to 1280x1024 at 60Hz
Low power dissipation (0.8W typical at 3.3V,
110MHz)
0.6~2.0V p-p analog input range
10k~1MHz HSYNC locking range
Full programmability via I2C interface
Support automatic screen positioning
Support automatic clock phase adjustment
TTL compatible digital inputs and outputs
High impedance tri-state output
Power-down mode
Single 3.3 volt power with 5 volt tolerant I/O
100-pin 14x20 mm PQFP package
CKEXT
IIC Interface
&
Control Logic
HSYNC
Digital
Logic
Circuits
VSYNC
CK REF
CP
RIN
T/H
ADC/R
Output
Logic
ROUT<7:0>
T/H
ADC/G
Output
Logic
GOUT<7:0>
T/H
ADC/B
Output
Logic
BOUT<7:0>
VRT
VN
VRB
GIN
VRT
VN
VRB
BIN
VRT
VN
VRB
/OE
AL875-01a functional block diagram.vsd
AL875A
DOC #: 1-F-PMK275-0001
VERSION 1.0
The AL875 is a high-speed triple 8-bit monolithic analog-to-digital converter (ADC) designed for
digitizing RGB graphics/video signal or other applications. Its 110 MHz conversion rate can
support display resolution of up to 1280x1024 at 60Hz refresh rate.
The AL875 accepts 0.6~2.0V analog input range without using pre-amplifiers which may reduce the
overall S/N ratio. Digitized data is piped at the full clock rate to the 24-bit output port. The AL875
uses 3.3V power with 5V tolerant I/O and low power dissipation.
The sampling clock is provided by an external clock source, usually a PLL, which multiplies the
frequency of the input reference clock (usually a HSYNC signal) to generate the sampling clock.
The AL875 provides a programmable PLL divider up to 4096.
In addition, the input active horizontal and vertical starting and ending positions can be detected to
ensure that the whole picture fits into the displayable region of the screen. Through an I2C interface,
the AL875 is fully programmable to support various graphic resolutions.
Analog graphic/video signals such as RGB, YCbCr and YPbPr can be digitized by the AL875. The
digitized data can then be processed by the AL250/251 line doubler, AL300 LCD controller, or
other proprietary designs for various applications.
Ordering Information
Part number
Package
Power supply
Maximum Operating Frequency
AL875
100-pin QFP
+3.3 volt
110MHz
For more information about the AL875 or other AverLogic products, please contact your local
authorized representatives, visit our website, or contact us directly.
DISTRIBUTED BY:
AL875A
DOC #: 1-F-PMK275-0001
VERSION 1.0