jk flipflop C

There are three operations that can be performed with a flip-flop: Set it to 1, reset it to 0, or complementits output. •With only a single input, the D flip-flop can set or reset the output, depending on the value of the D inputimmediately before the clock transition. •Synchronized by a clock signal, the JK flip-flop has two inputs and performs all three operations. The circuitdiagram of a JK flip-flop constructed with a D flip-flop and gates is shown in Fig. (a). The J input sets theflip-flop to 1, the K input resets it to 0, and when both inputs are enabled, the output is complemented. This can be verified by investigating the circuit applied to the D input: D = JQ’ + K’Q When J = 1 and K = 0, D = Q + Q = 1, so the next clock edge sets the output to 1. •When J = 0 and K = 1, D = 0, so the next clock edge resets the output to 0. •When both J = K = 1 and D = Q, the next clock edge complements the output. •When both J = K = 0 and D = Q, the clock edge leaves the output unchanged. •The graphic symbol for the JK flip-flop is shown in Fig. (b). It is similar to the graphicsymbol of the D flip-flop, except that now the inputs are marked J and K . The T (toggle) flip-flop is a complementing flip-flop and can be obtained from a JK flip-flopwhen inputs J and K are tied together. This is shown in Fig. (a). •When T = 0 (J = K = 0), a clock edge does not change the output. When T = 1 (J = K = 1), a clock edge complements the output. The complementing flip-flop is useful for designingbinary counters. •The T flip-flop can be constructed with a D flip-flop and an exclusive-OR gate as shown in Fig. (b). The expression for the D input is •When T = 0, D = Q and there is no change in the output. When T = 1, D = Q’ and the outputcomplements. The graphic symbol for this flip-flop has a T symbol in the input. Characteristic Tables•A characteristic table defines the logical properties of a flip-flop by describing itsoperation in tabular form. •The characteristic tables of three types of flip-flops define the next state (i.e., the state thatresults from a clock transition) as a function of the inputs and the present state. Q ( t ) refersto the present state (i.e., the state presentprior to the application of a clock edge). Q(t + 1) is the next state one clock period later. •Note that the clock edge input is not includedin the characteristic table, but is implied to occur between times t and t + 1. Thus, Q(t)denotes the state of the flip-flop immediatelybefore the clock edge, and Q(t + 1) denotesthe state that results from the clock transition.