NEC MultiSync LCD1920NX User And Service Manual page 97

The AD9884 is a complete 8-bit 140MSPS, monolithic graphics digitizer optimized for digitizing RGB
graphics signals from personal computers and workstations. Its 140MSPS encode rate capability and
full-power analog bandwidth of 500MHz supports display resolutions of up to 1280x1024 at 75Hz with
sufficient input bandwidth to accurately acquire and digitize each pixel. To minimize system cost and power
dissipation, the AD9884 includes +1.25V reference, PLL to generate a pixel clock from HSYNC and COAST,
and programmable gains, offset, and clamp control. The user provides only a +3.3V power supply, analog
input, and HSYNC and COAST signals. Three-state CMOS outputs may be powered from 2.5V to 3.3V.
The AD9884's on-chip PLL generates a pixel clock from HSYNC and COAST inputs. Pixel clock output
frequencies range from 20 to 140MHz. PLL clock jitters is 500ps p-p typical relative to the input reference.
When the COAST signal is presented, the PLL maintain its output frequency 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 external clock input provided as the pixel clock.
A clamp signal is generated internally or may be provided by the user through the CLAMP input pin. This
device is fully programmable via a two wire serial port. Fabricated in an advanced CMOS process, the
AD9884 is provided in a space-saving 128-lead MQFP surface mount plastic package and is specified over
the 0°C to +85°C temperature range.
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