I am currently working on a CCD based product that uses the AD9824 to digitise the CCD output. On the whole it works very well, but we have been experiencing occasional (approx 1 in 500) images where the colours are incorrect. There are several possibilities that may cause this effect, and one line of enquiry is based around the dc operation of the AD9824 and its immunity to spikes. Our application relies on the use of the PxGA as we need to run the different pixel colours at different gains. One scenario could be a sporadic dc shift that may cause an imbalance in the perceived colours due to one of the amplifiers limiting. I can see from the datasheet that there are three separate sections that control the quiescent point - dc restore on the input, CLPDM loop and CLPOB loop. Could you explain in a little more detail how each one is controlled, and why it is there as this may help to solve our problem. Thanks.
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