Snmek 1
Educational program: Mechanic electrician
Title of program: Technical training II. class Transistor as an
amplifierWorked out: Bc. Chumchal Miroslav
Projekt Anglicky v odbornch pedmtech, CZ.1.07/1.3.09/04.0002je
spolufinancovn Evropskm socilnm fondem a sttnm rozpotem esk
republiky.
Description of transistorSchematic markingConnection of
transistor in circuit, practical exerciseSpecificationDescription
of connectionControl question
Transistor as an amplification element
The transistor is active electronic semiconductor element, which
has amplification ability. It is created by couple of junctions
PN.Bipolar transistor has three outlets marked like B- base, K ( C
)- collector and E- emitter.This semiconductor element changing own
resistance so that between E and C would not pass through bigger
current, than is Beta multiple current, which pass through to the
control electrode B.Semiconductor transmitter is occurencing in two
types NPN and PNP. Their function is similar, but they are
different by opposite polarity. Where at the PNP current pass
through by one direction, at the NPN type pass through by opposite
direction.Description of transistor
Schematic mark of NPN, PNP transistor
Connection of transistor in circuit
Components Value R1 M1 R2 10K RC 2K7 RE 22K C1 M15 C2 2-10M T
Transistor NPN ( BC 549 )Specification
Influence of elements on amplifier workT silicon transistor,
amplifying bringing signal.C1 coupling capacitor separate direct-
current voltage from alternating element. C2 - coupling
capacitor.RC influence of working point of transistor.RE If it is
connection, it reduce reachable oscillation of output voltage.R1,
R2 setting of working point of transistor. The more current pass
through by divider, the more constant voltage is on base of
transistor.
Make a connection of given scheme on contact field and compare
function of transistor as a circuit breaker and as the amplifier.
Explain the different?Practical exercise for students
1.Question Explain function of transistor.2.Question Draw
schematic mark PNP and NPN of transistor.3.Question Replace
transistor KC 508 by transistor series BC.
Questions for students
Poznvme Elektroniku I.,Vclav Malina, Vydalo nakladatelstv
KOPP,esk Budjovice, 1996www.google/Wikipedie - zesilovaeVlastn
poznmkov seitLiterature used