SCAN FLIP-FLOP CIRCUIT WITH DEDICATED CLOCKS

摘要

In one form, a scan flip-flop includes a clock gating cell and a dedicated clock flip-flop. The clock gating cell provides an input clock input signal as a scan clock signal when a scan shift enable signal is active, and provides the input clock signal as a data clock signal when the scan shift enable signal is inactive. The dedicated clock flip-flop stores a data input signal and provides the data input signal, so stored, as a data output signal in response to transitions of the data clock signal, and stores a scan data input signal and provides the scan data input signal, so stored, as the data output signal in response to transitions of the scan clock signal. The clock gating cell may further provide the input clock signal as the data clock signal when both a scan shift enable signal is inactive and a data enable signal is active.

主权项

1. A scan flip-flop circuit comprising:
a clock gating cell for providing an input clock input signal as a scan clock signal when a scan enable signal is active, and for providing said input clock signal as a data clock signal when said scan enable signal is inactive; and a dedicated clock flip-flop for storing a data input signal and providing said data input signal, so stored, as a data output signal in response to transitions of said data clock signal, and for storing a scan data input signal and providing said scan data input signal, so stored, as said data output signal in response to transitions of said scan clock signal.