Pixel clock speeds in excess of 110 MHz can be achieved with the AD9981 by using a dual chip “ping-pong” configuration. A dual chip solution is different from an alternate pixel sampling solution in that full refresh rates can be maintained.
There are many ways to implement a dual AD9981 design. This application notes serves to make the user aware of the considerations that should be weighed when implementing this configuration. Among the variables are layout and routing constraints, clock selection, graphics controller requirements, and maximum speed requirements.
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