Sequential logic functions, sequential nature of the behavior, feedback, sequential and temporal logic elements, synchronous and asynchronous execution
Sequential logic functions, Sequential logic circuits

Unlike combinational logic circuits depending on the state sequential logic circuit outputs only the combination of the input, but also on the internal state of the circuit, which contains an internal digital memory. Digital memory is realized by bistable flip-members.

Flip-members can be bistable or monostable. The bistable flip-member is two possible steady-state equilibrium states. In each member state of bistable flip-flop will remain until changed. To zoom is possible to imagine a two-position switch.

The opposite is monostable member who has only one equilibrium. After impulse, which monostable member deflects out of balance, the member returns to its original state. An example of this can be a key element.

Another way to flip the distribution of members is on asynchronous and synchronous. In this case, it is seen to change in terms of time. For asynchronous flip members change the output depends only on the change of inputs. In synchronous flip members change occurs not only on the change of inputs, but also passes through a synchronization (clock) pulse.