How in common collector BJT configuration voltage gain is less than unity ?


The most striking characteristic of this configuration is that the input signal source must carry the full emitter current of the transistor, as indicated by the heavy arrows in the first illustration. As we know, the emitter current is greater than any other current in the transistor, being the sum of base and collector currents. In the last two amplifier configurations, the signal source was connected to the base lead of the transistor, thus handling the least current possible.

Because the input current exceeds all other currents in the circuit, including the output current, the current gain of this amplifier is actually less than 1 (notice how Rload is connected to the collector, thus carrying slightly less current than the signal source). In other words, it attenuates current rather than amplifying it. With common-emitter and common-collector amplifier configurations, the transistor parameter most closely associated with gain was β. In the common-base circuit, we follow another basic transistor parameter: the ratio between collector current and emitter current, which is a fraction always less than 1. This fractional value for any transistor is called the alpha ratio, or α ratio.

Comments

  1. They are a defionite ace iin the hole and a runaway favorite.
    The management of your time will be paramount
    to your success until such time as you aree able, both from a management
    and resource standpoint, to outsource. Regarding the puppy shots timeline and thee vaccine given to the puppy, it is important for the pet owner
    to knmow that it takes about 5 to 10 days for thhe vaccine to release the effects and
    strengthen the immunity of the puppy.

    Also vizit my blog: the simpsons tapped out cheats

    ReplyDelete
  2. Exceptional post however , I was wondering if you could write a litte more on this subject?

    I'd be very thankful if you could elaborate a little bit more.
    Kudos!

    Review my homepage gems for clashs of clans

    ReplyDelete

Post a Comment

Popular posts from this blog

COMMON COLLECTOR CONFIGURATION OF A TRANSISTOR

Give difference between inertial and non inertial frames of references?