Tektronix 454A - Circuit Operation

Ci r cui t Descr i p t i on- 454zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA ‘ / R 454A
r ect l y t r i gger e d by an ade qu at e t r i gger si gnal . T h e SI N G LE  Ci r cui t . T h e C R T Ci r cui t p r ovi d es t h e vol t ages an d cont ai ns
S WEEP p osi t i on al l ows one ( an d onl y one) swee p t o b e

t h e cont r ol s necessar y f or o p er at i on of t h e cat h o d e- r ay
i ni t i at e d af t er t h e ci r c u i t i s r eset wi t h t
h
e RE S
E
T b u t t on .

t u be .
T h e ‘ Swee p Gener at or ci r c u i t
al so
p
r oduces
an u
nbl an
k i ng
gat e
si gnal coi nci d ent wi t h t h e sawt oot h wavef or m
p
r o-
d uced by t h e ‘ Swee p Gener at or ci r c u i t . T h i s gat e si gnal

T h e
P
ower S u pp
l y
ci r cui t p r ovi d es t h e l ow- vol t age
unbl an k s t h e C R T t o p er mi t d i s p l ay p r esent at i on . Anot h er

power necessar y f or o p er at i o
n
of t h
i s i nst r ument . T h i s vol t -
gat e si gnal al so coi nci d ent wi t h t h e ‘ Swee p Ge n er at o r  age i s d i st r i b u t e d t o al l of t h e ci r c u i t s i n t h
e i nst r ument as
sawt oot h i s avai l abl e at t h e ‘ GAT E connect or on t h e i n-

s h own by t h e P ower Di st r i bu t i o n ci r cui t . T h i s ci r c u i t al so
st r ument si d e p anel . An al t er nat e sync p ul se p
r od
uce
d
i n

p r ovi d es t h e vol t age l evel s t o t h e PR O BE P O WER connec-
t h e ‘
Swee p  Gener at or

i s connect e d  t o t h e V er t i cal

t or s f or t h e o p er at i on of act i ve p r obe syst ems . T h e Cal i b r a-
Swi t c h i ng ci r cui t . T h i s pu l se swi t c h es t h e d i s p l ay bet ween

f or ci r c u i t pr o d uces ± s q uar e- wave o u t p ut wi t h acc u r at e
c h annel s at t h e e n d of eac h swee p w h en t h e M OD E swi t c h
 am p l i t ude an d f r e qu ency w h i c h can b e u se d t o c h ec k t h e
i s i n t h e A L T p osi t i on .

cal i br at i on of t h
i s i nst r u ment an d t h e com p ensat i on of
pr o b es .
T h
e
C URREN T PR O BE CA L l oop p r ovi d es an
acc u
r at e c u r r ent so u r ce f or cal i b r at i on of c u r r ent - measur i ng
T he ’ Swee p Gener at or ci r cui t i s b asi cal l y t h e same as

pr obe syst ems
.
t h e ‘ Swee p Gener at or ci r cui t . H owever , t h i s ci r c u i t onl y
p r o d u ces ± sawt oot h ou t p u t si gnal af t er ± d el ay t i me d et er -

CI RCUI T O PER ATI O N
mi ne d b y t h e ‘ ¤™œ• / DI V swi t c h an d t h e DELAY- TI ME
MUL
TI
PL I ER
d i al
.
I f t h e ’ S WEEP
M
OD E swi t c h i s set t o

Gener al
t h e ’ STA R TS A F T ER D EL AY
TI ME
p osi t i on,
t h e ’

T h i s sect i on pr ovi d es ± d et ai l e d d escr i p t i on of t h
e el ec-
Swee p Gener at or b egi ns t o pr o d u ce t h e swee p i mme d i at el y

t r i c ± l
o per at i on an d r el at i ons h i p of t h e ci r c u i t s i n t h e 454 ‘ .
f ol l owi ng t h e sel ect e d d el ay t i me . I f t h i s swi t c h i s i n t h e
T R I GG ER A BLE A F T ER D EL AY TI ME p osi t i on, t h e ’

The t h
eor y
of o p er at i on f or ci r cui t s u ni q u e t o t h i s i nst r u -
Swee p Gener at or ci r c u i t does not p r od u ce ± swee p unt i l i t

ment i s d escr i b
ed i n d et ai l i n t h i s d i scussi on . Ci r c u i t s w h i c h
r ecei ves ± t r i gger pu l se f r om t h e ’ Tr i gger
Gener at or ci r c u i t

ar e
commonl y u se d i n
t
h
e el ect r oni cs i n d ust r y ar e not d es-
r e e ¹ i t h e sel ect ed del ay t i me .

cr i b e d i n d et ai l . I f mor e i nf or mat i on
i s d esi r e d on t hese
af t

commonl y used ci r c u i t s, r ef er t o t h
e f ol l owi ng t ext b oo k s :
I n t h e M I X E D p osi t i on of t h
e
H
O
R I Z
DI S PL AY swi t c h ,

Te
k t r oni x Ci r c u i t Conce p t s B oo k s ( or d
er
f r om yo
u
r
t h e o u t p ut si gnal f r om t h e ’ Sweep Gener at or i s ±
com-

l ocal
Te
k
t r oni x F i el d Of f i ce or r epr esent at i ve) .
p osi t e sawt oot h wavef or m wi t h t h e sl o p e of t h e f i r st p ar t of
t h e wavef or m d et er mi ne d by t h e ‘ Swee p Gener at or , an d
 Cat h o d e- R
ay Tubes, Te kt r oni x P ar t
No .
062- 0852
t
h
e
sl o p
e of t h e secon d p ar t of t h e wavef or m d et er mi ne d  01 .
b y t h e ’ Swee p Gener at or .
Osci l l osco p e Tr i gger Ci r cui t s, Te k t r oni x P
ar t • ¿ . 062-
1056- 00 .
T h e o u t p ut of ei t h er t h e ‘ or ’ Swee p Gener at or ci r c u i t
i s am p l i f i e
d
by
t h e
H
or i zont al Am p l i f i er ci r c u i t t o p r o d u ce

P
ower
Su pp l y Ci r cui t s, Te k t r oni x P ar t No .
062- 0888-
h or i zont al d ef l ect i on f or t
h e C R T i n al l p osi t i ons of t he

01 .
H O R I Z DI S PL AY swi t c h except §
- Y . T h e H or i zont al
Am p l i f i er cont ai ns ± § 10 magni f i er t o i ncr ease
t
h
e swee p
 Swee p Gener at or Ci r cui t s,
Te
k
t r oni x P ar t No .
r at e t en t i mes i n
any
¤™œ• / DI V swi t c h p osi t i on .
Ot h er

062- 1098- 01 .
h or i zont al d ef l ect i o n si gnal s can be connect e d
t o t h e
H
or i -
zont al
Am p
l i f i er
by u si n g t h e § - ¥ mo d e of o p er at i on . T h
e

Osci l l osco p e

P r obe

Ci r c u i t s,

Te k t r oni x

P ar t

No .
§ si g n al i s connect e d
t o t
h
e H or i zont al Am p l i f i er ci r c u i t

062- 1146- 00 .
t h r o u g h t h e C h a nn el 1 V er t i cal P
r eamp ci r cui t an d t h e Tr i g-
ger P r eam p ci r c u i t , w h en t h e H
O R
I Z
DI S PL AY swi t c h i s

V er t i cal
Am p l i f i er Ci r cui t s, Te k t r oni x P ar t
No .
set t o § - ¥ an d t h e T RI GG ER swi t c h i s
set t o C H 1 O NL Y

062- 1145- 00
.
O R
§
- Y .
H or i zont al Am p l i f i er
Ci r cui t s, Te k t r oni x P ar t No .
062- 1144- 00 .
T h e – Axi s Am p l i f i er ci r cui t
d et er mi nes t h e C R T i nt en-
si t y an d bl an k i ng . T he – - Axi s
Am p l i f i er ci r c u i t s u ms t h e

Ph i l l i p
C u t l er , " Semi con d u ct or Ci r c u i t
Anal ysi s" ,
c u r r ent i n p ut s f r om t h e I N T EN SI TY
cont r ol , V er t i cal

M cGr aw- H i l l , N
ew Yor k , 1964 .
Swi t c h i ng ci r c
u i t ( c h o pp e d bl an k i ng) , ‘ an d ’
Swee p
Gener at or ci r c u i t ( unbl an k i ng) an d t h
e ext er nal – AXI S

L l oy d ¡ .
Hunt er ( E d . ) , " H an d boo k of
Semi con du ct or
I NPU T bi n d i ng p
ost . T h e o u t pu t l evel of t h e – Axi s
Am p l i -

E l ect r oni cs" , seco n d e d i t i on, M
cGr aw- H i l l , N ew Yor k ,
f i er ci r c u i t cont r ol s t h e t r ace
i nt ensi t y t h r o u g h t h e C R T

1962
.
3- 3