A master and a slave stage of a flip-flop are each separately clocked with
non-overlapping clock signals during scan mode to eliminate a data input
scan mode multiplexer. Separate, non-overlapping clocking permits the
elimination of hold violations in scan mode for scan mode flip flop
chains, permitting the elimination of delay buffers in the scan mode data
paths. Resulting application circuits have reduced circuit area, power
consumption and noise generation. A clock generator for scan mode
clocking is provided to obtain the separate, non-overlapping scan mode
clocks. Scan mode clocks may be generated with a toggle flip flop, a
pulse generator or a clock gating circuit.