An electronic circuit is a closed path or paths formed by the interconnection of electronic components through which electrical current can flow.
Physically, an electronic circuit can be as small as a pinhead or covering several miles. They are constructed by the connection of electronic components and drivers that allow electricity to flow between components. Integrated circuits are small circuits built from a piece of semi-conductors housed in a protective box. While large circuits can be built by assembling electronic components on a printed circuit board (PCB), which is used to mechanically support and electrically connect components. Integrated circuits are typically used as components of large circuits built on PCB. When components are connected by cable as the driver, the circuit can be expanded to cover or to connect a large area.
Pancras, perfboards or stripboards are common to test new designs. Which allow the designer to make rapid changes in the circuit during development.
Electronic circuits can display highly complex behavior, even if governed by the same laws of physics that simple circuits.
An electronic circuit can generally be classified as analog circuitry, digital circuitry, or mixed signal circuit (a combination of analog and digital circuits).