Patent attributes
A scan flip-flop includes a multiplexer, a first latch, a second latch, an output buffer and a clock buffer. The multiplexer selects one of a data input signal and a scan input signal based on an operation mode. The first latch latches an output of the multiplexer. The second latch latches an output of the first latch. The output buffer generates an output signal based on an output of the second latch. The clock buffer generates a first clock signal and a second clock signal that control operation of the first latch and the second latch. The first latch, the second latch, and the clock buffer are sequentially arranged along a first direction. A first clock line supplying the first clock signal and a second clock line supplying the second clock signal have a cross couple connection.