Sequential circuits #
- All small and large sequential circuits are made of flip-flops and set of combinational circuits.
- Contrary to combinational circuits, a sequential circuit design has states and transitions from current state to next state.
- A sequential circuit design problem is typically modeled as a finite state diagram (FSD).
- An FSD consists of circles as states and arrows as transitions, which specifies the behavior of the system.
Sequential circuit as a finite state machine #
- Finite state diagrams (FSD) describe the behavior of the system.
- Finite state machine design are categorized into Mealy, Moore, or hybrid.
- Mealy is a FSM whose output values are determined by its current state and current inputs.
- In contrast, Moore machines output values are determined solely by its current state.
- A register is used as a storage module to save the output of the combinational circuit.
To determine what gets loaded into the register, it depends on the enable bit and the input.
