Gated SR Latch (continued)
Characteristic Equation: The complete excitation table and state diagram of the gated SR latch are given in Figs. 6.14a and b.
From the excitation table the characteristic equation is derived: Q* = SC + RQ + CQ
Note that when C = 0 this equation reduces to Q* = Q which means that the present state is held.
When C = 1 the equation becomes: Q* = S + RQ, the characteristic equation of the simple SR latch, and thus the latch is enabled.