Search results
Results from the WOW.Com Content Network
The output of a flip-flop is constant until a pulse is applied to its "clock" input, upon which the input of the flip-flop is latched into its output. In a synchronous logic circuit, an electronic oscillator called the clock generates a string (sequence) of pulses, the "clock signal".
In digital computing, the Muller C-element (C-gate, hysteresis flip-flop, coincident flip-flop, or two-hand safety circuit) is a small binary logic circuit widely used in design of asynchronous circuits and systems. It outputs 0 when all inputs are 0, it outputs 1 when all inputs are 1, and it retains its output state otherwise.
Now the results of the test are captured in the target flip-flops. Re-assert scan mode, and see if the combinatorial test passed. In a chip that does not have a full scan design -- i.e., the chip has sequential circuits, such as memory elements that are not part of the scan chain, sequential pattern generation is required. Test pattern ...
Setting J = K = 0 maintains the current state. To synthesize a D flip-flop, simply set K equal to the complement of J (input J will act as input D). Similarly, to synthesize a T flip-flop, set K equal to J. The JK flip-flop is therefore a universal flip-flop, because it can be configured to work as an SR flip-flop, a D flip-flop, or a T flip-flop.
An alternative solution to clock gating is to use Clock Enable (CE) logic on synchronous data path employing the input multiplexer, e.g., for D type flip-flops: using C / Verilog language notation: Dff= CE? D: Q; where: Dff is D-input of D-type flip-flop, D is module information input (without CE input), Q is D-type flip-flop output.
Flip-flops only flip when triggered by the edge of the clock pulse, so changes to the logic signals throughout the circuit begin at the same time and at regular intervals. The output of all memory elements in a circuit is called the state of the circuit.
In a synchronous circuit, two registers, or flip-flops, are said to be "sequentially adjacent" if a logic path connects them. Given two sequentially adjacent registers R i and R j with clock arrival times at the source and destination register clock pins equal to T Ci and T Cj respectively, clock skew can be defined as: T skew i, j = T Ci − T Cj.
Gate level or combinational circuits which contain no storage (latches and/or flip flops) but only gates like NAND, OR, XOR, etc. Sequential circuits which contain storage. This fault model applies to gate level circuits, or a block of a sequential circuit which can be separated from the storage elements.