TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

[The] operation of an active device which is biased almost to output-current cut-off so that current flows only during one half of each cycle of sinusoidal input signal, i.e. the angle of flow is 180°.  3, record 1, English, - class%2DB%20operation

Record number: 1, Textual support number: 1 OBS

[The class-B] mode of operation ... is very efficient because the mean current of the active device is directly proportional to the signal amplitude and is almost zero for zero input signal. The output signal is ... a reproduction of only one half of each cycle of input signal but linear amplification is possible by using two class-B stages in push-pull operation and most of the output stages in transistor amplifiers and receivers are of this type.  3, record 1, English, - class%2DB%20operation

Record number: 1, Textual support number: 2 OBS

The theoretical efficiency of a class-B stage (measured by the ratio of the output power to the power taken from the supply) is 78% and efficiencies approaching this value can be obtained in practice.  3, record 1, English, - class%2DB%20operation

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

L'amplification d'un signal à enveloppe variable par un TEC [transistor à effet de champ] fonctionnant en classe A résultent de faibles performances en rendement. Le fonctionnement en classe B permet une forte amélioration du rendement mais au détriment d'une réduction du gain en puissance. La classe A permet de conserver le gain de la classe A en permettant d'atteindre un niveau de rendement pratiquement égal à celui obtenu en classe B.  2, record 1, French, - fonctionnement%20en%20classe%20B

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

[The] operation of an active device in which the bias and signal amplitude are so chosen that output current flows throughout each cycle of input signal (assumed sinusoidal), i.e. the angle of flow is 360°.  3, record 2, English, - class%2DA%20operation

Record number: 2, Textual support number: 1 CONT

Class-A operation. Class-A amplifier operation is characterized by a conduction period of the output current (collector or drain) of 360°. That is, the operating point is chosen to have a constant voltage and current. In effect, the amplifier power is on all the time. This is referred to as linear operation. By operating in the linear region of the transistor's characteristics, the amplified signal suffers minimum distortion. This comes at a price of inefficiency in the amplifier. The theoretical maximum possible efficiency of a class-A amplifier is 50%, but due to linearity requirements of the applications, the efficiency may be no more that 25%.  4, record 2, English, - class%2DA%20operation

Record 2,  Textual support,  French

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

[The] operation of an active device which is biased beyond cut-off of output current so that current flows for less than one half-cycle of sinusoidal input signal, i.e. the angle of flow is less than 180°.  3, record 3, English, - class%2DC%20operation

Record number: 3, Textual support number: 1 OBS

[The class-C] mode of operation ... cannot be used for linear amplification but is extensively used for RF amplification, e.g. in transmitters where a tuned output-load circuit rejects harmonics and gives a sinsoidal output signal. Efficiency (measured by the ratio of the output power to the power taken from the supply) can be very high indeed - approaching 90%.  3, record 3, English, - class%2DC%20operation

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

Dans un fonctionnement en classe C, la forme impulsionnelle du courant de sortie permet de maximiser le rendement de collecteur ou de drain du transistor. Malheureusement, la chute du gain en puissance est très significative par rapport aux fonctionnements en classe AB ou B. Ceci nuit fortement aux performances en rendement en puissance ajoutée qui sera plus faible qu'en classe B.  2, record 3, French, - fonctionnement%20en%20classe%20C

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 DEF

The operation of an electronic tube in such a way that output current flows for appreciably more than half but for less than the whole of the electrical cycle when a pure sinusoidal input signal is used.  1, record 4, English, - class%20AB%20operation

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 DEF

Fonctionnement d'un tube électronique de façon telle que le courant de sortie circule pendant sensiblement plus de la moitié, mais moins de la totalité, du cycle électrique lorsque le signal d'entrée est sinusoïdal pur.  1, record 4, French, - fonctionnement%20en%20classe%20AB

Record 4,  Textual support,  Spanish