CONFIGURABLE MUX-D SCAN FLIP-FLOP DESIGN

A method, computer program storage device and apparatus are provided for flexible observability during a scan. In one aspect of the present invention, a method is provided. The method includes providing a selector load input to at least a portion of a scan chain, selecting an observe-only scan mode for the at least a portion of the scan chain based at least upon the selector load input, and providing a data input to a storage element in the scan chain based at least upon the observe-only scan mode. The apparatus includes a first scan chain multiplexor comprising a selector input, a first input terminal, a second input terminal and an output terminal. The apparatus also includes a first scan chain storage element comprising an input terminal and an output terminal, where the input terminal of the first scan chain storage element is communicatively coupled to the output terminal of the first scan chain multiplexor. The apparatus further recites that the output terminal of the first scan chain storage element is communicatively coupled to the first input terminal of the first scan chain multiplexor. The computer program storage device adapts a manufacturing facility to create the apparatus.