Abstract: According to an embodiment, a digital circuit with N number of redundant flip-flops is provided, each having a data input coupled to a common data signal. The digital circuit operates in a functional mode and a test mode. During test mode, a first flip-flop is arranged as part of a test path and N?1 flip-flops are arranged as shadow logic. A test pattern at the common data signal is provided and a test output signal is observed at an output terminal of the first flip-flop to determine faults within a test path of the first flip-flop. At the same cycle, the test output signals of each of the N?1 number of redundant flip-flops is observed through the functional path to determine faults.

Abstract: According to an embodiment, a digital circuit with N number of redundant flip-flops is provided, each having a data input coupled to a common data signal. The digital circuit operates in a functional mode and a test mode. During test mode, a first flip-flop is arranged as part of a test path and N-1 flip-flops are arranged as shadow logic. A test pattern at the common data signal is provided and a test output signal is observed at an output terminal of the first flip-flop to determine faults within a test path of the first flip-flop. At the same cycle, the test output signals of each of the N-1 number of redundant flip-flops is observed through the functional path to determine faults.

Abstract: According to an embodiment, a method for testing a triple-voting flop (TVF) is provided. The method includes providing a first and a second scan enable signal by a control circuit to, respectively, a first scan flip-flop and a third scan flip-flop of the TVF; receiving a third scan enable signal at the second scan flip-flop of the TVF; providing a scan input signal to the first scan flip-flop, the second scan flip-flop, and the third scan flip-flop; controlling the first scan enable signal, the second scan enable signal, and the third scan enable signal; receiving, at an output of the TVF, a scan output signal; and determining whether the TVF suffers from a fault based on the scan output signal and the controlling of the first scan enable signal, the second scan enable signal, and the third scan enable signal.

Abstract: According to an embodiment, a method for testing a triple-voting flop (TVF) is provided. The method includes providing a first and a second scan enable signal by a control circuit to, respectively, a first scan flip-flop and a third scan flip-flop of the TVF; receiving a third scan enable signal at the second scan flip-flop of the TVF; providing a scan input signal to the first scan flip-flop, the second scan flip-flop, and the third scan flip-flop; controlling the first scan enable signal, the second scan enable signal, and the third scan enable signal; receiving, at an output of the TVF, a scan output signal; and determining whether the TVF suffers from a fault based on the scan output signal and the controlling of the first scan enable signal, the second scan enable signal, and the third scan enable signal.

Abstract: In an embodiment, an integrated circuit includes: a voting circuit including N scan flip-flops, where N is an odd number greater than or equal to 3, and where the N scan flip-flops includes a first scan flip-flop and a second scan flip-flop, where an output of the first scan flip-flop is coupled to a scan input of the second scan flip-flop; a scan chain including the N scan flip-flops of the voting circuit, and third and fourth scan flip-flops, the scan chain configured to receive a scan enable signal; and a scan enable control circuit configured to control a scan enable input of the first or second scan flip-flops based on the scan enable signal and based on a scan input of the third scan flip-flop or an output of the fourth scan flip-flop.

Abstract: In an embodiment, an integrated circuit includes: a voting circuit including N scan flip-flops, where N is an odd number greater than or equal to 3, and where the N scan flip-flops includes a first scan flip-flop and a second scan flip-flop, where an output of the first scan flip-flop is coupled to a scan input of the second scan flip-flop; a scan chain including the N scan flip-flops of the voting circuit, and third and fourth scan flip-flops, the scan chain configured to receive a scan enable signal; and a scan enable control circuit configured to control a scan enable input of the first or second scan flip-flops based on the scan enable signal and based on a scan input of the third scan flip-flop or an output of the fourth scan flip-flop.