An electronic circuit is a closed path that is made up of connection and interconnections of electronic components through which an electric current can flow. Circuits contain electric components such as transistors and/or vacuum tubes; at least one of these components must manipulate voltage or current within the circuit. Electronic circuit design is categorized in three different ways:
1. Analog circuits
2. Digital circuits
3. Mixed-signal electronic circuit
Analog Circuit Design
Analog circuits are those whose signals may vary continuously with time in order to correspond to information being represented. The basic units included in this electronic circuit design are passive (resistors, inductors, capacitors, and memristors) and active. Analog circuits have two main designs: series circuits and parallel circuits. Analog circuits make up electronic equipment such as televisions, radios, voltage amplifiers, and tuning circuits.
Discrete Circuit Design
In digital circuits, electric signals take on discrete values independent of time in order to represent logical and numeric values. These values stand for the information being processed. A main component of the discrete circuit the transistor, a combination of which can be used to create logic gates. The gates can then be used together in order to create a desired output based on the input.
Larger digital circuits can contain a number of complex components like field-programmable gate arrays (FGPAs) or microprocessors. Along with other components, these can be interconnected in order to create a large circuit that is capable of operating on a large amount of data. Electronics that use digital circuits are calculators, microprocessors, and digital wristwatches.
Mixed-Signal Circuit Design
Mixed-signal or hybrid circuits contain elements of both analog and digital circuits on a single conductor die. These circuits are typically used to convert analog to digital signals so that digital devices can process the signals. Mixed-signal electronic circuit design is essential for components of FM tuners in digital products that have digital amplifiers, such as media players.
Other examples of products using mixed-signal circuits are timers, digital-to-analog converters (DACs), and analog-to-digital converters (ADCs). Any analog signal – whether it be a light wave, sound, or an FM radio signal – can be digitized using an ADC, The most energy efficient of these is the mixed-signal circuit.