Transistor Principle

Isolatie

This animation shows the transistor effect as the transistor is made to alter its state from a starting condition of conductivity (switched 'on', full current flow) to a final condition of insulation (switched 'off', no current flow). The animation begins with current flowing through the transistor from the emitter (point E) to the collector (point C). When a negative voltage is applied to the base (point B), electrons in the base region are pushed ('like' charges repel, in this case both negative) back creating insulation boundaries. The current flow from point E to point C stops. The transistor's state has been changed from a conductor to an insulator.

Geleiding

This animation shows the transistor effect as the transistor is made to alter its state from a starting condition of insulation (switched 'off', no current flow) to a final condition of conductivity (switched 'on', full current flow). The animation begins with the transistor acting as an insulator. In order to have it conduct, positive voltage must be applied to the base (point B). As opposite charges attract (in this case, positive and negative), electrons are 'pulled' out of the insulation boundaries and flow out of the base region at point B. The barriers that once restricted flow of electrons from the emitter to the collector are diminished. Electrons begin to flow in at the emitter (point E), through the base to the collector (point C). The transistor's state has been changed from an insulator to a conductor.

Versterking

This animation demonstrates how a transistor functions in a circuit. As it begins, the transistor is acting as an insulator-- that is when there are no sound waves activating the transistor, it simply blocks the flow of current through the circuit. But as the microphone converts incoming sound waves into waves of positive electrical current, the current travels along the left side of the circuit to the transistor and pumps electrons out of the base region. A large surge of electrons rushes through the transistor and transforms the weak incoming current into a stronger copy of itself. This stronger current then travels along the right side of the circuit to the speaker where it exits as amplified sound. Met toestemming van Lucent. Copyright © 2001 Lucent Technologies. All rights reserved. Informatie: D.J.F. Scheper