摘要 |
A charge coupled device analog-to-digital converter includes a plurality of charge storage stages that are arranged in a serial pipeline register and are connected to pass input source charges from stage to stage down the pipeline register. A reference charge generator and a charge splitter at each stage generate two fixed reference signals. The first of the reference signals is compared by a comparator to a source charge that is temporarily stored at the stage. The comparator generates a binary 1 if the source charge is greater than or equal to the first reference charge and a binary 0 if the source charge is less than the first reference charge. If a binary 1 is generated, only the stored contents of the stage pass to the next successive stage. However, if a binary 0 is generated, the charge contents of the stage is passed to a next successive stage and the second reference charge is also passed by a transfer gate to the next successive stage, where the charges are combined. Buffer registers are provided to temporarily store the output bits of the comparators of the stages to form a digital word for each source charge packet as the packet and associated added charge components leave the pipeline. |