05257223 is referenced by 98 patents and cites 7 patents.

A scannable flip-flop circuit allows data at its data input or its scan input to be stored in the flip-flop at its data output or shifted out of the flip-flop at its scan output. The flip-flop provides control circuitry for selecting the source of the input data and scan data. Data stored at the flip-flop data output may also be shifted out at the scan output. During scan operations, additional control circuitry allows data stored at the data outputs to be preserved.

Title
Flip-flop circuit with controllable copying between slave and scan latches
Application Number
7/791868
Publication Number
5257223
Application Date
November 13, 1991
Publication Date
October 26, 1993
Inventor
Bulent I Dervisoglu
Framingham
MA, US
Agent
Richard F Schuette
Assignee
Hewlett Packard Company
CA, US
IPC
H03K 3/289
G11C 19/00
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