Dual-edge-triggered flip-flops including scan, reset, and data retention features

A method, comprising:

• outputting a data signal or a scan signal based on a shift control signal;
• sequentially propagating the outputted data signal or scan signal to first and second nodes in response to rising and falling edges of a clock signal, respectively;
• and
• sequentially propagating the data signal or the scan signal at the first and second nodes to a third node based on the rising and falling edges of the clock signal, respectively.

An apparatus, comprising:

• a first latch including an input configured to receive an input data signal, and a clock input configured to receive a complementary clock signal;
• a second latch including an input configured to receive the input data signal, and a clock input configured to receive a non-complementary clock signal;
• a multiplexer including inputs coupled to outputs of the first and second latches, respectively, and an output configured to generate an output data signal;
• and
• a first data retention (DR) latch configured to:
• store a value of the output data signal at the output of the multiplexer in response to a first control signal;
• and
• restore the value of the output data signal to the output of the multiplexer in response to a second control signal.

A method, comprising:

• sequentially propagating a data signal to first and second nodes in response to rising and falling edges of a clock signal, respectively;
• sequentially propagating the data signal at the first and second nodes to a third node based on the rising and falling edges of the clock signal, respectively;
• retaining a value of the data signal at the third node in response to a first control signal;
• and
• restoring the value of the data signal at the third node in response to a second control signal.