Zusammenfassung der Ressource
What is an
amplifier?
- Electronic device
that increases
the voltage,
current or power
of a signal.
- Kind of
uses
- Wireless
Communication
- Acoustic pickups
- Audio equipment
- Boardcasting
- Classification
- Weak-signal
amplifier
- Wireless
recivers
- Commonly
found in FET
- Power
amplifier
- Transmitters
- Commonly found in
bipolar transistor
- Characheristic
- Gain
- It's the
increase in
signal power
- Symbolized with letter 'A',
and expressed in decibel
- Bandwidth
- Range of frequencies
for which the
amplifier gives
"satisfactory
performance"
- Efficiency
- Measure of
how much of
the
powersource is
usefully applied
to the
amplifier's
output
- Cascade application
- Used when a
single-stage
amplifier is not
sufficent for a
particular
purpose
- This configuration is created by
connecting 2 or more amplifiers
one after another
- The total gain is the
product of each gain
- Inconvenience
- Noise and distorsion
- Unwanted signal that degrade
the desired signal content in
the system
- It's found in 2 different types, the
first it the noise generated by the
system itself and the second is the
noise recived in the input
- To avoid these
problem a general
techinque called
negative feedback is
used.
- Portion of the output is fed back and
compared with the input signal to
stabilise amplification and reduce
distortion