| 摘要 |
<p>Scan chain links (306-310) which step data through a scan chain (306-310) using only a single control signal, and which require a reduced number of transistors to scan data into and out of a latch (300-304). One scan chain link (308), which allows the output of a scanned latch (302) to "wiggle", uses eight transistors and only a single control signal (SHIFT). Another scan chain link (308), which prevents the output of a scanned latch (302) from "wiggling", and which allows data to be maintained in the latch during a scan operation if it is so desired, uses twenty-five transistors and two control signals: one control signal (SHIFT) for stepping data through a scan chain, and an additional control signal (SCANNING) for preventing the output of a scanned latch from wiggling. <IMAGE></p> |
