A reference circuit is a hypothetical electric circuit of specified equivalent length and configuration

Computer configuration

In communications or computer systems, a configuration is an arrangement of functional units according to their nature, number, and chief characteristics. Often, configuration pertains to the choice of hardware, software, firmware, and documentation...

, and having a defined transmission characteristic or characteristics, used primarily as a reference for measuring the performance of other, i.e., real, circuits or as a guide for planning and engineering of circuits and networks.

Normally, several types of reference circuits are defined, with different configurations, because communications

Telecommunication

Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

 are required over a wide range of distances. Another type of reference circuit shows how to configure integrated circuits into function blocks, which Analog Devices provides for electrical design engineers. Analog Devices' Circuits from the Lab reference circuits are fully tested and come with the schematics, evaluation boards, and device drivers necessary for system integration. A group of related reference circuits is also called a reference system.