fowe Ansplen
Non
elecha
Ap
TanduceAnpAnpA
cadTaneduce
Amplfiee System
A lasa sign Paplfle must ofeu
largt rd be Capab le of hwding
wdts to hundeds of oats
The ders f2uakst coneesen of owe
he poue
C cit Hhe ma anot power
Hhat the citeliit Capable
and,impdance natelin to
herdrdevte
Hhe
Lasge po
gk neissy thak
at
ohy in electtonic sysrem.
Prece de alsass
poLOe abov
amp bloc
in the, abet
does not
om
1kdeaos
convet
0we' he
to usefu
ANaLLabe aoth outpumina
the 0Lse
Thes, a pouse, amplf may be
deined
oho a ino
a devic that coyge s
Poule and
acbon controlled by
inpu sighal
The tsansisto ks employed
plwve tiaHsistoree
Called
* Detee, bekseen vatzge and Pacee
Ampiies
The primasey function votage Ampi
is to ra the votage levd o dsaon
the sinal
a vey utlk p0we can be Rom
En orde to achieve high volkag
ampifaion
Vin zRin
Rin
) transistors having thin bale (bih p)
sisttne) s kept qut loo
wRin (input esistance)
compoasion bo Re(collectoe lad
bigh couech Load (Re
which s necessary to give igh
votge
the votage npfies
oeseated at Loo coechk
Re is
aloags
urrent,
amfiud
insize,
and
becase
oeight cheape
idmneley
cost
oceupies ess space.
to
dolivee hasae
it bas t6 harle larg
b orde
am iications
to achieve h pow e
eized PoLetoansistors ase
wse the
to lisspahe
heat íodieed in tansistose during
opeehion
') tanscoe having thìck base (small p)
ae
currunt
)
v)
colector esistan ce Re
krnso rme
is made
fo imedance maleng
clasa A POo
ansistote
biased that the o/p urrent
MowsAOke the entire cycle a the
t t
2) Class pows Amplupuc SO
Ypetransise
biased that the olp currnt floes
only dusing posibv halt ccle af
h this
this' tAPe, currint fows
cably lecs than half
Amplifie 4luee
The characteeacstic
anpliie Le to behocen those
cláce A and class B anpfes
more than
but iss tta he nire
ige
Diret Coupled.
Clacu A fooe
Cin
Vee trarsistt
hd ie desived
The ten seues fd
connectod oibh. the
transsto usd PoostansishO
he
the
rang LQtts
The charact'stie oith
shoon belo !
poine
Tea and Vee&. and coleeo no
oUecor cuvent
Tespectively
(
cmin
Ve mín
When je
an dc. Appied, the
sinal isand'doon
opsutng point At
cauwng djg current "aed vouge to vary
Current ncale to
t0 Icmin ' Similaky
bhe colectoe-emitte votege increaset'
Veema ahd falla to Veemin
Lhput PoLave from coleae ppy
Fnlde) VecIca
Yousee
used dseaonAom collectoe Supply
Çombenents,
i) esPruopkhekAissipated in the colectoe
uthe dl vided into
powen developed acrasS he.
resiso constiuig ac po uoek
otpt
Tout(ac
the
vafues couectoh chrent
and colecto to emitte voltey'
ouklac=Temax Ydesna
Vcemax
Vemaz
94 2x4 Re
dissipakd ' the fotem of heat
b) Pouex transistk itself the Cause
at co lectu jnchong Sinee,
(10
colleete base jwcion s Teveese
mare feg ured to
Cross his Åwhchoo, ohic
dissipated tthe ok.m of beat
Nobe?
) With Zero
A
to zero and
the
Teduees
trancistke
l the
Be
the
rm heat
Thub a transisoe
Roe nder
Aissipaea
Zero
mazimn
slgnal Condition
ohen Conle
thanwth Slgnal conition
dqeation = ero anal ratinge
to
transistoe
sing
reswling
the signal ma
max ofpoint mid-
Si
Cdludabon
man
kno2
W
nCde)
Vec
Re
Vec
2R
Mmae 25
(13)
das A
# Transforende Coupled cass A Pooee
Ampiieeiu so Called,
ialedsigta single
ended
One
pouea
ansisOe
mpliFle (uztng onty
cae of Aisect coupled class
cent
current (Ts) hro the
colecoee resisRveLoa (Re) shich
oaduisable to ab&
olp devie
fote these reasons. n arrangemen
wing a Suebleansfome
the Load t ampbhiealso
pesmits inpdanc' matzhing
Co
4)
Opezahng Chaachshcc cs
bilow'
IemaL
IDc load ine
2Vee
Lemin
Veemin
Veemax
neglble resisznce n primary
Asswning,0no across the
ordes to adhieve
owkput Temax =2c8 NeEmaxa2Vee
((5
he vasu ahon of colctore votae
a peaes across trassfot mo
voleye
ransfokneo ohich s wen develops
and Supples to the
Ciuait Andysis
Tn an dea tansarmete thee is no
volzg drop n primaey . So, VeEQ =Vee
PoLestnntto tns istor
Pout lac)
Ralde
outlac)
Undo po cond on voco ltege
Suings om to o nd lect
cuirntVrms tom
2/2
Neenaz -2Vec
Vres Vec
16)
LemaxLemin
Ac
poce developed across the
Bouta
100
24
50/
(()
B ouer
The transistok Angiaso baled
thut Zero Co lechok curnt
Zer
he opekaing point is st
Opeka ng Characteache Curve u choon:
Vce
(12
Enpt pouwek, Rinlde) =VecIye
currentten from
vaue of caleete o
bhen
Jemax sin 9d
2T
Temaz
211
Vec Temax
RMs vealue f colechor current
RMS value of
(19)
busing hale cyde
Loutlac)
Vmaze
4
Hese,
haf cyele
foutlac)
Pincdc
Veemax
4
single ended
detan
opokahon, ppreeiable distonis
itredeed
Suni condueto becawe af non-incaity of
evice ?Sueh a distin
b mayR be u duce
geaty
ofesahnenshlayin
rs in a snge
single st
Pasic work
The signa
Panciplei
before ampicah O0,nt oo
Signala
10 hade tekence Each these
4 thes inpuk to one
Pthe trahsistoe Gf the js h pull
åmbuie: ince tbe inputs to the ho0
tuastors ase g0" out ef phasey so
he ops of the trans)stoks:
The, olp tTans for met is co nne ctec
in the coectoe ciuts of tthe
tansistotS is such a cay that the
collecto Cweens of too reunsstus
çombine to provde an ovetAl signal
hawng Same aveform as that of
orifhal sgnal The' magnitude
nsequent rae
to
in eolec potental
decreades Cire push .Herce
neucedpeatons
name push- puu The
Oveall vO taye
anakrme
isLeOnto the
The
beloo'
Notett
anticlodeo e
t
Consideed psitie
clocw, curnt
ngave
t
22
t
23
this combined lendinal ia langeethan
the. input
Tre
M
N
R
The eDne enite
connecked togethek: The input signal
tuoo ansistors
cenre ta
Ira ovdes posite sianau to
the Oseninu
cONnected do th
of both the dianaistors alees
endf output
twninals of
tansfokme
centu
re
tupped primasy
he powve
supply' Nee is conne ched bhoen'emi tee
4 olp hiansfomee Resishors Rand oR
wscd to provide bas Rote
the ciout The
QcreSs
The un aho
Load RA
proponnected
Suondasy of olp ransfoemes
ansor mee À Chose So makeh
amgii and thesefoke tanss
The j escent "utrents
bronsonen
Oqeahon:
when the base at one toansistOre
posihive, he collectok cutUnE(Iu)
Ahees a deeSuase is.
coleche porati
cpuhvehoeveto
At te' same time
feVese achon
aive
od
a
e he
Causkj dececebaseCurren deeleeales,
