Abstract: A circuit includes an input block and a combinational logic block. The input block has reconfigurable latches that are connected serially during testing times such that an output of one of the latches is connected to an input of a successive latch. The latches are directly connected to first level gates of the combinational logic block. The combinational logic block contains switches that prevent the propagation of signals through the combinational logic block during testing times other than when a desired vector is loaded into the latches. The switches disconnect the power and/or ground from the first level gates. The switches further connect the outputs of the first level gates to power or ground, depending on the type of transistors used in the first level gates. The switches alternatively delay the output through a pair of inverters and resupply the output to itself if refreshing the output is desired.