A full-scan latch is provided that may be used to incorporate design for
test functionality in an integrated circuit. The full-scan latch includes
a shadow latch, a multiplexer, and a slave latch. The full-scan latch has
a test mode and a normal mode. When in the normal mode, the device
operates as a transparent latch, passing a data input to its output. When
in test mode, the device is operable to pass scan data down a scan chain
and to inject scan data into the data path.