US Patent 7218542 Physical priority encoder

A priority encoder can be used for a Content-Addressable Memory (CAM) device that typically has an array of CAM cells arranged in columns and rows with each row having a match signal indicative that compare data has matched data within the respective row. A priority encoder is operatively connected to the array of CAM cells and determines a highest priority matching address for data within the array of CAM cells. The priority encoder includes match lines associated with respective rows and precharged bus lines connected into respective match lines that are discharged whenever there is a match signal such that the highest precharged bus line discharged results in an encoded address.