Download transistors 3

Tutorial: Mechanic - electrician
Topic: Technical training
II. class
Transistors 3
Prepared by: Melichařík Lubomír
Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002
je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.
 BIPOLAR
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TRANSISTOR
- is a three-layer component comprised of various
subsidized areas
- emitter is, in contrast to the base, by several orders of
magnitude more subsidized, has much more free
charge carrier (NPN transistor with a common emitter)
electrons, and they flood a thin area base
- increase the positive voltage between the base and
emitter thinning area without free carriers at the
interface base and emitter
- voltage around 0.6 V to 0.7 V (Si) starts PN junction
base-emitter leading the electric current. This part of
the transistor behaves as a classical semiconductor
diode.
- applying a positive voltage between the collector and
emitter, the excess electrons will be extracted from the
base toward the collector.
 Conditions
for correct operation
of the transistor are :
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- A thin layer of base - the essence of the
phenomenon of transistor.
- emitter doped more than base
- base doped more than the collector
- in bipolar transistor lead current also
holes
- Therefore, this type of transistor is called
"bipolar".
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Basic connection
Involvement of transistor amplifier with a common
emitter.
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In electronic circuits there can be a transistor
connected four basic ways. According to the
electrodes, which is common for input and output
signal with a distinctive involvement:
Involvement of a common emitter (SE) - reverse
phase, current and voltage gain is much greater
than 1
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Involvement of the common base (SB) - nonreverse stage, a small current gain (Ai<1), very low
input impedance, high voltage gain (similar size as
that of SE), in connection with the use of switches
or sources in part stabilization.
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Involvement of the common collector (SC)
(=Emitter follower) - non-reverse phase, a large
input impedance, large current gain, voltage gain is
less (<1), is used in monitoring the circuit.
 1.
Name the basic properties
of the bipolar transistor.
 2.
Name the basic conditions
for the proper functioning of
the transistor.
1. Draw the circuit diagram of
transistor amplifier with a common
emitter.
 2. Draw the circuit diagram of the
transistor with a common emitter (SE).
 3. Draw the circuit diagram of a
transistor with a common base (SB).
 4. Draw a connection transistor with a
common-collector (SC).
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Václav Malina
Adrian Schommers
3-92608-32-5
Poznáváme elektroniku I.
Elektronika tajemství zbavená. ISBN