PPT Slide
Synchronous sequential digital systems
Outputs of a combinational circuit depend only on current inputs
- after sufficient time has elapsed
Sequential circuits have memory
- even after waiting for the transient activity to finish
The steady-state abstraction is so useful that most designers use a form of it when constructing sequential circuits:
- the memory of a system is represented as its state
- changes in system state are only allowed to occur at specific times controlled by an external periodic clock
- the clock period is the time that elapses between state changes it must be sufficiently long so that the system reaches a steady-state before the next state change at the end of the period