UltraScan: using time-division demultiplexing/multiplexing (TDDM/TDM) with VirtualScan for test cost reduction

This paper describes time-division demultiplexing and multiplexing of high-data-rate scan patterns applied on I/O's into low-data-rate scan patterns applied on VirtualScan compression circuitry to further reduce test application time and test pin-count without coverage loss