1445326735900-0

Starting electronics
T-type bistable
One particular mode of operation of the JK-type bistable is
of importance here. If both J and K inputs are held at logic 1,
the outputs of the master bistable will change state with each
rising edge of the clock signal and the final outputs will change
state for each falling edge. Such a fact is used as the basis of
the T-type bistable (where T stands for ‘toggle’), shown in
Figure 11.12. The lone T input of this circuit is really just the
CLK inputs of other bistables.
Figure 11.12
A T-type bistable
And that concludes our look at how logic bistable circuits are
made up from basic logic gates. The important point about
all of this though, is that by taking basic combinational logic
gates and joining them in what are fairly basic circuits, we
have created sequential circuits — that is, logic circuits that
have an element of memory!
260