Bridge circuit

Bridge circuit

A bridge circuit is a type of electrical circuit in which the current in a conductor splits into two parallel paths and then recombines into a single conductor, thereby enclosing a loop. It was originally used for measurement purposes, but can also be used in power supplies.

The best-known bridge circuit, the Wheatstone bridge, was invented by Samuel Hunter Christie and popularized by Charles Wheatstone, and is used for measuring resistance. It is constructed from four resistors, one of which has an unknown value (Rx), one of which is variable (R2), and two of which are fixed and equal (R1 and R3), connected as the sides of a square. Two opposite corners of the square are connected to a source of electrical current, such as a battery. A galvanometer is connected across the other two opposite corners. The variable resistor is adjusted until the galvanometer reads zero. It is then known that the ratio between the variable resistor and its neighbour is equal to the ratio between the unknown resistor and its neighbour, and this enables the value of the unknown resistor to be calculated.

The Wheatstone bridge has also been developed to measure impedance in AC circuits, resulting in designs such as the Wien bridge, the Maxwell bridge and the Heaviside bridge. All are based on the same principle, which is to compare the output of two potentiometers sharing a common source.

In power supply design, a bridge circuit or bridge rectifier is an arrangement of diodes or similar devices used to rectify an electric current, i.e. to convert it from an unknown or alternating polarity to a direct current of known polarity.

In some motor controllers, a H-bridge is used to control the direction the motor turns.

See also

* Fontana bridge
* Graetz bridge
* Kelvin bridge
* Lattice filter
* Maxwell bridge
* Phantom circuit - a use of balanced bridge circuits
* Wheatstone bridge
* Wien bridge oscillator
* Bridge T circuit

External links

* [http://www.allaboutcircuits.com/vol_1/chpt_8/10.html Bridge circuits] - Chapter 8 from an online book.
* [http://www.ecelab.com/bridge-circuits.htm Wien, Shering, Hay, Owen, Maxwell, and Resonance Bridges] - With balance equations


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • bridge circuit — tiltelio grandinė statusas T sritis automatika atitikmenys: angl. bridge circuit vok. Brückenkreis, m; Brückenschaltung, f rus. мостовая схема, f; мостовая цепь, f pranc. circuit en pont, m …   Automatikos terminų žodynas

  • bridge circuit — tiltelio grandinė statusas T sritis fizika atitikmenys: angl. bridge circuit vok. Brückenschaltung, f rus. мостиковая схема, f; мостовая схема, f pranc. circuit en pont, m; montage en pont, m …   Fizikos terminų žodynas

  • bridge circuit — noun a circuit consisting of two branches (4 arms arranged in a diamond configuration) across which a meter is connected • Syn: ↑bridge • Hypernyms: ↑circuit, ↑electrical circuit, ↑electric circuit • Hyponyms: ↑Wheatstone bridge …   Useful english dictionary

  • bridge circuit — Elect. bridge1 (def. 9). [1930 35] * * * …   Universalium

  • Bridge (disambiguation) — A bridge is a structure built so that a transportation route can cross above an obstacle.Bridge can also refer to:In entertainment*Bridge (card game disambiguation), multiple card games *Bridge (instrument), the device that anchors the strings to …   Wikipedia

  • bridge — bridge1 bridgeable, adj. bridgeless, adj. bridgelike, adj. /brij/, n., v., bridged, bridging, adj. n. 1. a structure spanning and providing passage over a river, chasm, road, or the like. 2. a connecting, transitional, or intermediate route or… …   Universalium

  • Circuit bending — Probing for bends using a jeweler s screwdriver and alligator clips Circuit bending is the creative customization of the circuits within electronic devices such as low voltage, battery powered guitar effects, children s toys and small digital… …   Wikipedia

  • circuit en pont — tiltelio grandinė statusas T sritis automatika atitikmenys: angl. bridge circuit vok. Brückenkreis, m; Brückenschaltung, f rus. мостовая схема, f; мостовая цепь, f pranc. circuit en pont, m …   Automatikos terminų žodynas

  • circuit en pont — tiltelio grandinė statusas T sritis fizika atitikmenys: angl. bridge circuit vok. Brückenschaltung, f rus. мостиковая схема, f; мостовая схема, f pranc. circuit en pont, m; montage en pont, m …   Fizikos terminų žodynas

  • Circuit de Silverstone — Caractéristiques générales Lieu Silverstone (Angleterre) Coordonnées …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”