442 Revised Lab Manual w07

8/10/2019 442 Revised Lab Manual w07

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ELECTRICAL ENGINEERING DEPARTMENT

California Polytechnic State University

SIGNAL TRANSMISSION LABORATORY

EE 442(revised version)

Winter 2007

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1



EE 442 SI!"# $%"!S&ISSI'! #"'%"$'%

Pa*e

"c+no,led*eents

Personal #a.oratory !ote.oo+ and $he #a.oratory %e/ort0-1

#a. " $ie 3oain $ransission #ine "nalysis"-1

#a. Sinsoidal Steady-State $ransission #ine "nalysis-1

0-1

#a. 1 $he !et,or+ "naly5er 1-1

#a. C $ransission #ine %eflection Coefficient6 I/edance and the Sith ChartC-1

#a. 2 I/edance &easreents .y 2 and 4 #ines 2-1

#a. 8 $ransission #ine Paraeters 8-1

#a. 4 Use of the Sith Chart for #ine-#en*th and #ine-#oss Corrections 4-1

#a. 9 $he Slotted #ine $echni:e for #oad I/edance &easreents 9-1

#a. ; I/edance &atchin* .y the Sin*le-St. $nin* &ethod ;-1

#a. 7 I/edance &atchin* .y the 3o.le-St. $nin* &ethod 7-1

#a. 3 I/edance &atchin* ,ith Sin*le- and 3o.le-St. $nin*3-1

#a. E Introdction to Electrical Perforance "nalysis of Printed Circit oards E-1

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Acknowledgements

$he Si*nal $ransission #a.oratory &anal ,as initially develo/ed in 1P =794" net,or+ analy5ers into the

la.oratory crricl $he anal allo,ed Cal Poly stdents to se net,or+ analy5ers

in their stdy of transission lines6 and ,as sed for EE 8986 a concrrent la.oratorycorse for the si*nal transission line lectre corse6 EE 818 $he ne?t a@or revision of

the anal ,as /erfored .y 3r 3ean "ra+a+i >is revision of the EE 898 la. anal

,as sedfor ,as sed for the 2008-09 catalo* crricl revision for theelectroa*netic corses $he ne, si*nal transission la.oratory corse ,as desi*nated

EE 4426 a la.oratory ta+en concrrently ,ith the ne, desi*nated lectre EE 402 In

antici/ation of ne, revisions for addressin* the theory of transission lines first in the

/resentation of the t,o lectre se:ence (EE 889 and EE 402) and a crricl chan*eto allo, the la.oratory to .e ta+en concrrently ,ith the first electroa*netic lectre

corse EE 8896 3r Ai >arris revised the anal .y develo/in* the five la.s " thr E

$his revision incor/orated the donation in Ball 200; of ten ne, 200&>5 di*ital

oscillosco/es (3S' 8202") fro "*ilent $echnolo*ies and antici/ated the 2007-0


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PERSONAL LABORATORY NOTEBOOK ANDTHE LABORATORY REPORT

Personal ond #a.oratory !ote.oo+Each stdent enrolled in this la.oratory class shold docent their e?/erience in EE 442

in a /ersonal .ond note.oo+6 sin* the forat and +no,led*e that they have *ained in

other Cal Poly la.oratory corses $his note.oo+ ,ill not .e *raded >o,ever6 this/ersonal .ond note.oo+ (= D ? 11 *rid /a/er recoended) ,ill .e sed as the only

reference ,hen ta+in* the la. final for this corse In addition6 this e?/erience ,ill

contine the develo/ent of the docentation of la.oratory e?/eriences for all Cal Poly*radates %ee.er - the criteria for yor docentation in this note.oo+ is that a /eer

cold se the contents to re/rodce yor reslts ,ith the identical e:i/ent Please

refer to the ,rite-/ at the end of this section for soe notes on the forat and content of

this note.oo+ (and the re/ort)

$he #a.oratory %e/ort

$he la.oratory re/ort develo/ed after the co/letion of each la. activity is the ain

/rodct of the teas ,or+ that is sed for evalation of /erforance Writin* effectivetechnical re/orts is a vala.le s+ill that ,ill enhance yor /rofessional career

$he /r/ose of the la.oratory re/ort is to descri.e the easreent /rocedre6 la.

reslts6 and analysis /rocedre6 and to inter/ret and discss the reslts $he conclsions

indicate the +no,led*e *ained .y co/letin* the e?/erients

$here is no one .est forat for all technical re/orts6 .t the follo,in* forat is

recoended

Ttle !nd d!te

L!" te!m mem"e#s

P$#%ose

E&$%ment

Inclde I3 n.ers

P#oced$#e

Circit dia*ras for all easreents ta+en6 ,ith varia.les defined on dia*ra3escri.e easreent /rocedres sed so a /eer cold re/eat

Chronolo*ical record of ,hat ,as acco/lished6 incldin* any /ro.les

%ecord all easreents directly either se/arately6 in a ta.le6 or ,ith a *ra/hF follo,

forat for ta.les and *ra/hs /resented in the ,rite-/ at the end of this sectionInclde forlas for all calclations ,ith one sa/le of actal vales sed

!ote all /ro.les encontered

Inde? the docentation ,ith any n.erin* sed in the anal6 if a//ro/riate

Concl$sons

Co/arison of the e?/ected otcoes of the e?/erient6 derived fro theory or

co/ter silation6 to easred vales 'ne ,ay to co/are lti/le data sets is to/lot theoretical /rediction and e?/eriental data on one *ra/h sin* different line styles

to distin*ish each data set

" critical /art of the conclsion is error analysis Co/arison .et,een theoretical and

e?/eriental reslts ,ill not al,ays reslt in /erfect a*reeent


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Ind'd$!l %!#!g#!%(s )#om e!c( o) t(e te!m mem"e#s " tho*htfl6 reflective

/ara*ra/h ,hich discsses ,hat has .een learned drin* this la.oratory e?/erience6

,hich is si*ned and dated


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EE 442 $ie 3oain $ransission #ine "nalysis #a. "

Pr/ose $his /ro@ect introdces the stdent to the tie doain res/onse of transission lines $he effects

of tie (or /ro/a*ation) delay cased .y a transission line to the ste/ res/onse of a five different loads,ill .e investi*ated atched6 isatched6 o/en circit6 short circit6 and /arallel %C $he reslts ,ill .e

discssed in the conte?t of the /erforance of /ractical di*ital circits $he ste/ res/onse of each load ,ill

.e investi*ated in three ,ays sin* a silation ,ith PS/ice6 a atheatical analysis6 and a easreentcircit Bor each case6 the reslts of each investi*ation ,ill .e co/ared

%eferences

EE 402 $e?t Is+ander6 &a*dy BF Electroa*netic Bields and WavesF Waveland PressF 2000Cha/ter 76 es/ecially sections 71-P 8812 Bnction enerator"*ilent 3S'8202" 'scillosco/e

2 = % 9="U ca.le

8 short (arond 80 c) % 9="U ca.les

2 !C $ees1 !C to do.le .anana ada/ter

!C-do.le .anana 90 oh load resistorF 10 oh resistorF o/en circitF short circit6 /arallel %C load (90

oh and 1;0 /B)

PS/ice on ,or+station co/ter

3iscssion

In this e?/erient6 ,e ,ill se a techni:e first /resented in yor lo,er division circits la.oratory too.serve the ste/ res/onse of a circit $he techni:e is to se an a//ro/riately chosen s:are,ave to

/eriodically re/eat a /ositive ste/ in/t to a circit !ote that a /ositive 3C offset is a//lied to the

s:are,ave so that the s:are,ave a//ears to @st .e a /ositive /lse $hen only the /ositive /ortion of the

s:are,ave is o.servedF ho,ever6 nothin* /revents o.servation of the effects of the second half of the

s:are,ave $he /eriod $ of the s:are,ave is deterined so that the ste/ res/onse of the circit isessentially in steady state at a tie $26 ie6 half the /eriod $his techni:e allo,s the /eriodic volta*es

o.served ,ith an oscillosco/e to .e the co/lete ste/ res/onse $he sae .asic techni:e is sed to

/rovide the in/t volta*e ,avefor for a PS/ice silation (see the te/late code .elo,)

$he ni:e featre of this /ro@ect is that ,ith relatively ine?/ensive6 lo, /erforance instrentation and

a lon* transission line (1;)6 ,e can sho, the tie doain effects of ,ave /ro/a*ation6 ie6 the ste/

res/onse of a circit ,ith /ro/a*ation delay nder different loadin* conditions $he o.served volta*es/resent the sae /henoena as a /ractical circit ,hich has diensions coensrate ,ith the

,avelen*th of its si*nals6 di G H v/ f6 ,here di is the diension of the circit6 H is the ,avelen*th in

the edia of the circit6 v/ is the velocity of /ro/a*ation in the edia of the circit6 and f is the fre:ency

of the si*nal (volta*e) In this /ro@ect the transission line is an % 9= "U ,hich has a velocity of/ro/a*ation of a.ot 2 ? 10=s6 ,hich yields a /ro/a*ation delay of a.ot =0 ns for a 1; ca.le $hs

,ith a ;0&>5 sco/e and a 1 &>5 s:are,ave fnction *enerator (and /ro/erly chosen vales for the %Cload to *et a reasona.le tie constant)6 the effects of the /ro/a*ation delay can .e easred

!ote that the characteristic i/edance of the % 9="U is 90 ohs $he ot/t i/edance of the >P8812" fnction *enerator also is 90 ohs6 so the sorce (fnction *enerator) is atched to the transission

line $his follo,s .ecase the sall len*th of transission line (a.ot 80 c) ,hich connects the fnction

*enerator to the oscillosco/e also is % 9= "U and is atched to the sorce $he effect of the loadin* of

the oscillosco/e ot/t i/edance (/arallel 1 &oh and 14 /B) also is ne*li*i.le as the tie constant deto the ot/t i/edance and connectin* transission lines is estiated to .e less than 1ns6 and therefore

too sall to o.serve $he effect of the oscillosco/e i/edance can .e silated tho*h


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Part I (Prela.) PS/ice Silation

Usin* PS/ice6 silate the follo,in* circit for five cases sin* P%'E to dis/lay J(2) and J(8)

a) 90 oh atched load.) 10 oh isatched load

c) o/en circit

d) short circit

e) /arallel %C load (90 oh and 1;0 /B)Bor each case6 /rovide a co/y of the P%'E ot/t for J(2) and J(8)6 and a one /ara*ra/h descri/tion of

,hy the ,avefor for J(2) has the sha/e /resented in the silation "lso6 to /re/are for the e?/erient

read the Part II (la.oratory /ro@ect)6 and in /articlar6 revie, the E?/ " "nalysis notes $he E?/ "

"nalysis notes /resents a atheatical odel for the ste/ res/onse of the transission line circits thatstdents ,ill .e as+ed to se to /redict and to nderstand the /henoena o.served

J(2) J(8)

Bi*re 1 $ransission #ine &easreent Circit

Use the follo,in* te/late PS/ice code to constrct yor silation

Kee 442 e?/ " tie doain analysis tlLrc

K/arallel rc load 90 oh and 1;0 /B

v* 1 0 /lse(0 1 0 1ns 1ns 9s 1s) F0 to 1J /lse6 0 delay6 1ns risefall tie6 09s ,idth6 1s /eriodr* 1 2 90

t1 2 0 8 0 5090 td=0n Flossless $# in/t 2 06 ot/t 8 06 Mo90ohs6 tie delay =0ns

r1 8 0 90

c1 8 0 1;0/tran 01n 900n 0 01n Ftransient analysis 01ns /rint ste/6 900 ns dration6

Ftstart0 (initial /rint vale)6 ta?01 (a? internal ste/ si5e)/ro.e

end

Part II (la.oratory /ro@ect)

a) &atched 90 ohs #oad

1 $he silation and analysis ,ill no, .e verified ,ith easreents Constrct the transission line

circit *iven in Bi*re 1 Use J(2) as the channel 1 in/t and tri**erF connect the first $ee on the sco/echannel 1 connection Connect the .anana load ,ith 90 oh resistor directly to the first $ee (no

transission line)6 and o.serve the volta*e J(2) for an in/t volta*e of 1 &>5 s:are ,ave ,ith 10 J//

and N900J 3C offset Provide a s+etch of the volta*e J(2)

2 Connect the atched load ,ith a 1; eter transission line6 and connect J(8) to channel 2 of the sco/e

(se the second $ee) Usin* the sae in/t volta*e6 o.serve the volta*es J(2) and J(8) for each case

Provide s+etches of the volta*es J(2) and J(8) on the sae fi*re

8 Use the analytic for /resented in the analysis to /rovide s+etches for the volta*es J(2) and J(8)

Co/are the reslts of the silation6 analysis6 and easreentF ho, close are theyO

B

BB

SC'PE

$# % 9="U (1;) #'"3

d


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3iscssion !otice that ,ith a atched load6 the reflection coefficient of the load # 06 and the vale of

the reflected (ne*ative *oin*) ,ave is 5ero >o,ever the delay o.served can have a deleterios effect on

the /erforance of a synchronos (cloc+ed) di*ital circit $he delay in the si*nal can i/act the

satisfaction of the set-/ tie re:ireent for fli/-flo/s Jaria.le delays cased .y different len*th si*naltraces can case cloc+ s+e,6 ,here the ed*e of a cloc+ ,avefor ,ill occr at different ties for different

fli/-flo/s "lso6 the a?i delay liits the ini cloc+ /eriod that can .e sed6 ie6 the /eriod

st .e lar*er than the a?i delay for correct synchronos si*nal inter/retation

.) &isatched 10 ohs #oad

1 Connect the .anana load ,ith 10 oh resistor directly to the first $ee (no transission line)6 and o.serve

the volta*e J(2) for the sae sorce volta*e Provide a s+etch of the volta*e J(2)

2 Connect the isatched load ,ith a 1; eter transission line6 and connect J(8) to channel 2 of the

sco/e (se the second $ee) Usin* the sae in/t volta*e6 o.serve the volta*es J(2) and J(8) for each

case Provide s+etches of the volta*es J(2) and J(8) on the sae fi*re



3iscssion !otice that ,ith a isatched load6 the reflection coefficient of the load # -0;;6 and the

vale of the a/litde of the reflected (ne*ative *oin*) ,ave is -088J !o, there is not only a delay inthe res/onse for J(8) at the load6 .t there is a reflected ,ave that affects the J(2) ,avefor at the sorce

>ence6 the ,avefor volta*e at J(2) does not reain constant at 09J6 and after the reflected ,ave arrives6

has another vale (,hat is itO) !ote that this case is only an e?a/le of a isatch load6 and that othervales of a load resistance not e:al to Mo ,ill case different vales for J(2) in the steady state $his

chan*e cold affect the inter/retation of the di*ital lo*ic level at the sorce and at the load6 and hence *ive

rise to i/ro/er circit /erforance

c) '/en Circit #oad

1 Connect the o/en circit load directly to the first $ee (no transission line)6 and o.serve the volta*e J(2)

for the sae sorce volta*e Provide a s+etch of the volta*e J(2)

2 Connect the o/en circit load ,ith a 1; eter transission line6 and connect J(8) to channel 2 of the

sco/e (se the second $ee) Usin* the sae in/t volta*e6 o.serve the volta*es J(2) and J(8) for eachcase Provide s+etches of the volta*es J(2) and J(8) on the sae fi*re



3iscssion $he o/en circit load sho,s the effect of a tie delay of a.ot =0 ns $he initial J(2) is the/ositive *oin* ,ave only $he chan*e in the vale of volta*e at the load deonstrates the creation of the

ne*ative *oin* ,aveF note that # 16 ie6 the /ositive and ne*ative volta*e ,ave are e:al !otice ,hat

ha//ens at the sorce after the reflected ,ave arrives "t this /oint in tie6 the transission line is in

steady-state6 ie6 it has a constant volta*e 'n a /rinted circit .oard6 the effect o.served can .e cased .ya trace that is not connected6 leadin* to s/rios vales >o,ever6 the effect can .e sed to advanta*eF the

PCI .s interface sed in PCs ses an o/en circit at each end of the .s to increase the volta*e level of the

si*nal lines thro*h the se of the reflected ,ave fro the o/en circits

d) Short Circit #oad

1 Connect the short circit load directly to the first $ee (no transission line)6 and o.serve the volta*e

J(2) for the sae sorce volta*e Provide a s+etch of the volta*e J(2)

2 Connect the short circit load ,ith a 1; eter transission line6 and connect J(8) to channel 2 of the




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3iscssion !otice the delay in o.tainin* a vale of the volta*e at the sorce of 0JF a*ain6 there is atransient res/onse .efore the steady-state vales are o.served for the transission line " PC trace ,hich

is shorted to *rond ,ill have the sae .ehavior $he reflection coefficient of the load is # -16 ie6 the

ne*ative volta*e ,ave is the ne*ative of the /ositive volta*e ,ave $his leads to the steady-state vale of

crrent (short circit crrent) ,hich is liited .y the vale of the fnction *enerator ot/t i/edance,hich is 90 ohs and ,hich is atched ,ith the characteristic i/edance of the transission line6 Mo 90

ohs

e) Parallel %C load1 Connect the .anana /arallel %C load ,ith 90 oh and 1;0 /B directly to the first $ee (no transission

line)6 and o.serve the volta*e J(2) for the sae sorce volta*e !ote that the load resistor is atched to Moand the tie constant is ch less than the transission line delay Provide a s+etch of the volta*e J(2)

2 Connect the /arallel %C load ,ith a 1; eter transission line6 and connect J(8) to channel 2 of the



8 Use the analytic for /resented in the analysis to /rovide s+etches for the volta*es J(2) and J(8)Co/are the reslts of the silation6 analysis6 and easreentF ho, close are theyO

3iscssion $he /arallel %C load is a odel for a atched load ,hich has a /arasitic ca/acitance connectedin /arallel to it "ll connections (nodes) on a PC co/rise a t,o condctor syste6 ,hich is a ca/acitorF

a ty/ical rle of th. is that there are 1 /B at every node de to this effect $his intrinsic /arasitic

ca/acitance effect is a fndaental liitation for the in/t to any electronic circit6 and ,as reco*ni5ed .y

ode in the 1


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EE 442 Sinsoidal Steady-State $ransission #ine "nalysis #a.

Pr/ose $his /ro@ect ,ill introdce the stdent to the sinsoidal steady-state res/onse of

transission lines $he effects of tie delay cased .y a transission line (or /ro/a*ation delay)

to the sinsoidal in/t and the deterination of the sinsoidal steady-state res/onse of five

different loads ,ill .e investi*ated atched6 isatched6 o/en circit6 short circit6 and /arallel%C $he reslts ,ill .e discssed in the conte?t of the /erforance of /ractical circits $he

sinsoidal steady-state res/onse of each load ,ill .e investi*ated in three ,ays sin* a

silation ,ith PS/ice6 an analysis6 and a easreent circit Bor each case6 the reslts of each

investi*ation ,ill .e co/ared

%eferences

EE 402 $e?t Is+ander6 &a*dy BF Electroa*netic Bields and WavesF Waveland PressF 2000

Cha/ter 76 es/ecially sections 710-18

E:i/ent

>P 8812 Bnction enerator

"*ilent 3S'8202" 'scillosco/e

2 = % 9="U ca.le

8 short (arond 80 c) % 9="U ca.les

2 !C $ees

1 !C to do.le .anana ada/ter

!C-do.le .anana 90 oh load resistorF 10 oh resistorF o/en circitF short circit6 /arallel

%C load (90 oh and 1;0 /B)PS/ice on ,or+station co/ter

3iscssionIn this /ro@ect6 yo ,ill se a techni:e first /resented in yor lo,er division circits la.oratory

to o.serve the sinsoidal steady-state res/onse of a circit $he techni:e is to o.serve the

res/onse of a sinsoidal in/t volta*e ,ith an oscillosco/e to deterine the a/litde and /hase

sin* the tie .ase easreent of the oscillosco/e to convert the tie difference .et,een t,o

sinsoids at the sae fre:ency to a /hase difference $he sae .asic techni:e is sed for a

PS/ice silation (see the te/late code .elo,) >o,ever6 yo ,ill se the PS/ice transient

analysis ,hich ,ill allo, yo to see the co/lete res/onse6 ,hich ,ill consist of a transient /art

.efore the res/onse .e*ins the steady-state /art $he circit yo ,ill se is sho,n .elo,6 and as

in the #a. " yo ,ill investi*ate five different loads o ,ill se the P%'E ot/t to dis/lay

the sorce volta*e6 J(2)6 the volta*e at the id/oint of the transission line6 J(8)6 and the load

volta*e6 J(8)6 for each of the five different loads

$he ni:e featre of this /ro@ect is that ,ith relatively ine?/ensive6 lo, /erforance

instrentation and a lon* transission line (1;)6 ,e can sho, the tie doain and fre:ency

doain effects of ,ave /ro/a*ation6 ie6 the sinsoidal steady-state res/onse of a circit ,ith/ro/a*ation delay nder different loadin* conditions $he o.served volta*es /resent the sae

/henoena as a /ractical circit ,hich has diensions coensrate ,ith the ,avelen*th of its

si*nals6 di G H v/ f6 ,here di is the diension of the circit6 H is the ,avelen*th in the

edia of the circit6 v/ is the velocity of /ro/a*ation in the edia of the circit6 and f is the

1-


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fre:ency of the si*nal (volta*e) In this /ro@ect the transission line is an % 9= "U ,hich has

a velocity of /ro/a*ation of a.ot 2 ? 10=s6 ,hich yields a /ro/a*ation delay of a.ot =0 ns

for a 1; ca.le $hs ,ith a ;0&>5 sco/e and a 10 &>5 sinsoidal volta*e fro the fnction

*enerator (and /ro/erly chosen vales for the %C load to *et a reasona.le i/edance)6 the effects

of the /ro/a*ation delay on the /hase of the sinsoidal volta*e can .e easred

!ote that the characteristic i/edance of the % 9="U is 90 ohs $he ot/t i/edance ofthe >P 8812 fnction *enerator also is 90 ohs6 so the sorce (fnction *enerator) is atched to

the transission line $his follo,s .ecase the sall len*th of transission line (a.ot 80 c)

,hich connects the fnction *enerator to the oscillosco/e also is % 9= "U and is atched to

the sorce $he effect of the loadin* of the oscillosco/e ot/t i/edance (/arallel 1 &oh and

14 /B) also is ne*li*i.le6 and therefore too sall to o.serve $he effect of the oscillosco/e

i/edance can .e silated tho*h


Bi*re 1 $ransission #ine &easreent Circit

Usin* PS/ice6 silate the follo,in* circit for five cases sin* P%'E to dis/lay J(2)6 J(8)6

and J(4)a) 90 oh atched load

.) 10 oh isatched load

c) o/en circitd) short circite) /arallel %C load (90 oh and 1;0 /B)

Bor each case6 /rovide a co/y of the P%'E ot/t for J(2)6 J(8)6 and J(4)F annotate the dis/lay

to indicate the load silated !ote that all the ,avefors are in steady-steady after 1;0 ns

$hat is6 the sorce is atched and after the reflected volta*e reaches the sorce end6 there is no

ore reflections added to the transission line volta*e and the sinsoidal volta*es reain

constant in a/litde and /hase ,ith res/ect to each other (@st li+e that oscillosco/e dis/lay in

yor circits la. did) Usin* the in/t sinsoid as the reference6 se the P%'E ot/t to

easre the a/litdes of each of the three volta*es6 and easre the tie difference .et,een

J(2) as the reference sinsoid and J(8) and J(4) $hen calclate the /hase difference6 a*ain

sin* J(2) as the reference6 sin* the fact that the /hase can .e calclated fro 2K/iKfK td6 ,here

td is the tie difference and f10&>56 and the /hase nits are in radians $hen revie, thesinsoidal steady-state analysis of a transission line ,ith varios loads /resented in the

atheatical analysis6 and calclate the /hasor volta*es J(2)6 J(8)6 and J(4) !ote that yo ,ill

have to se the e?/ression for J(5) to calclate J(8) "lso note that yo ,ill have to relate the40ns delay for each transission line into an e:ivalent /hase difference sin* the e?/ression

2K/iKfK td a*ain !ote that the /hasor for J(2)6 the sorce6 ,ill not have a /hase of 0 de*rees for

the analytic calclation6 and therefore yo ,ill have to s.tract this calclated /hase an*le fro

the /hasors J(8) and J(4) to *et the corres/ondin* /hases differences In the analysis6 there areters li+e e?/(-@R5) for 5l and 5l2 ,here l is the len*th of the transission line and R is the

2-


15/51

/hase constant for the transission line With the tie delay for the len*th l of the transission

line *iven .y $l6 ,here is the /ro/a*ation velocity of the transission line and ,ith R6

ters li+e Rl and Rl2 are e:al to $ and $26 res/ectively %eferencin* the /hasor volta*es to

the sorce volta*e J(2)6 sari5e yor reslts in a ta.le ,hich /resents the /hasor a/litde6

tie difference and corres/ondin* /hase ,ith res/ect to J(2) for each of the three volta*es frothe easreents fro yor P%'E silation and those derived fro the analytical

calclation Coent on any discre/ancies that occr (the t,o vales shold .e very close)Use the follo,in* te/late PS/ice code to constrct yor silation

K/s/ice #a. sinsoidal steady state tlLacLrc

K/arallel rc load 90 oh and 1;0 /B

v* 1 0 sin (0 1v 10e*) FJ'0J offset6 J"1J a/litde6 10&>5 fre:ency

r* 1 2 90

t1 2 0 8 0 5090 td40n Flossless $# in/t 2 06 ot/t 8 06 Mo90ohs6 tie

delay 40ns

t1 8 0 4 0 5090 td40n Flossless $# in/t 8 06 ot/t 4 06 Mo90ohs6 tie

delay 40ns

r1 4 0 90

c1 4 0 1;0/tran 01n 800n 0 01n Ftransient analysis 01ns /rint ste/6 800ns dration6

Ftstart0 (initial /rint vale)6 ta?01n (a? internal ste/ si5e)

/ro.e

end


a) &atched 90 ohs #oad

1 $he silation and analysis ,ill no, .e verified ,ith easreents Constrct the

transission line circit *iven in Bi*re 1 Use J(2) as the channel 1 in/t and tri**erF connect

the first $ee on the sco/e channel 1 connection Connect the .anana load ,ith 90 oh resistor

directly to the first $ee (no transission line)6 and o.serve the volta*e J(2) for an in/t volta*eof 10 &>5 sine ,ave ,ith 10 J/+

2 Connect the atched load ,ith a 1; eter transission line6 and connect J(4) to channel 2 of

the sco/e (se the second $ee) Usin* the sae in/t volta*e6 /rovide s+etches of the volta*es

J(2) and J(4) 3eterine the a/litdes and tie difference6 and the /hasor re/resentation for

the t,o volta*es J(2) and J(4)6 ie6 the co/le? n.er that re/resents the a/litde and /haseof each

8 Co/are the /hasor reslts of J(2) and J(4) (a/litde6 tie difference6 and /hase difference)

of the silation6 analysis6 and easreentF ho, close are theyO

3iscssion !otice that ,ith a atched load6 the reflection coefficient of the load # 06 and thevale of the reflected (ne*ative *oin*) ,ave is 5ero >o,ever the delay o.served de to the

transission line is e:ivalent to a /hase shift of the ot/t volta*e of the transission line

relative to the in/t volta*e of the transission line

.) &isatched 10 ohs #oad

1 Connect the .anana load ,ith 10 oh resistor directly to the first $ee (no transission line)6

and o.serve the volta*e J(2) for the sae sorce volta*e

8-


16/51


17/51



3iscssion !otice the delay in o.tainin* the steady-state vale of the a/litde volta*e at the

sorceF a*ain6 there is a transient res/onse .efore the steady-state vales are o.served for thetransission line !ote the /hase shift in the steady-state vale of J(2) ,ith res/ect to the initial

sinsoidal volta*e /hase for J(2) de to the transission line " PC trace ,hich is shorted to*rond ,ill have the sae .ehavior $he reflection coefficient of the load is # -16 ie6 the

ne*ative volta*e ,ave is the ne*ative of the /ositive volta*e ,ave $his leads to the steady-state

vale of crrent (short circit crrent) ,hich is liited .y the vale of the fnction *enerator

ot/t i/edance ,hich is 90 ohs and ,hich is atched ,ith the characteristic i/edance of

the transission line6 Mo 90 ohs

e) Parallel %C load

1 Connect the .anana /arallel %C load ,ith 90 oh and 1;0 /B directly to the first $ee (no

transission line)6 and o.serve the volta*e J(2) for the sae sorce volta*e !ote that the load

resistor is atched to Mo.t the i/edance of the %C load is not e:al to Mo

2 Connect the /arallel %C load ,ith a 1; eter transission line6 and connect J(4) to channel 2of the sco/e (se the second $ee) Usin* the sae in/t volta*e6 /rovide s+etches of the volta*es

J(2) and J(4) 3eterine the a/litdes and tie difference6 and the /hasor re/resentation for

the t,o volta*es J(2) and J(4)6 ie6 the co/le? n.er that re/resents the a/litde and /hase

of each



3iscssion $he /arallel %C load is a odel for a atched load ,hich has a /arasitic ca/acitance

connected in /arallel to it "ll connections (nodes) on a PC co/rise a t,o condctor syste6

,hich is a ca/acitorF a ty/ical rle of th. is that there are 1 /B at every node de to this effect

$his intrinsic /arasitic ca/acitance effect is a fndaental liitation for the in/t to anyelectronic circit6 and ,as reco*ni5ed .y ode in the 1


18/51

;-


19/51

7-


20/51


21/51

8) S,ee/ atofast6 +no. controls s,ee/ s/eed (trn cloc+,ise to dis/lay solid

line)

4) Jideo Bilter trn off (liits .and,idth of s,ee/ fre:ency)9) $nin* initially set to 790 &>5

;) &ar+ers set to 90 &>5 s/acin* !ote ,ith s,ee/ ,idth set to fll ran*e (4 Q

1800 &>5) and ar+ers off6 one ar+er ,ill reain at the dis/layed fre:ency7) 't/t d set to V 0 d to avoid satratin* the %6 "6 and in/ts

=) Intensity trn cloc+,ise ntil trace can .e seen

P =794"

!et,or+ "naly5er

%%B 't "

%

"

$est

Port 3U$

3eviceUnder

$est

E:al#en*th

#ines

Incident

%eflected

$ransitted

Bi*re 1 Confi*ration for $ransission &easreent


22/51

$he a.ove channel settin*s ena.le a siltaneos dis/lay of d a*nitde and /hase for

the device nder test (3U$)

) $ransission &easreent Cali.ration of the >P =794" !et,or+ "naly5er

1) Connect the %B 't/t of the >P =794" to the Bl+e 7220" fre:ency conter

(90 in/t) and cali.rate the >P =794" fre:ency dis/layF initially se 790 &>5

2) Set the %B In/t "ttenation +no. for the >P =902" $est Set to 0 d8) Connect a thrX for the device nder test (3U$)

4) Set C%$ dis/lay on >P =794" to linear (release /olar "% .tton)6 s,ee/ ato6

fast6 +no. trned to ri*ht6 ot/t d set to V 0 d

9) Channel 1 select %6 set reference ,heel to 06 /ress offset .tton and ad@stntil the Ch 1 reference level is o.tained (cali.rates a*nitde level to the 3U$

/lane)

;) Channel 2 select Phase %6 set reference ,heel to 06 /ress offset .tton and

ad@st ntil the Ch 2 reference level is o.tained (cali.rates /hase level to the 3U$/lane)

Part II $ransission &easreents

1) %e/lace thrX ,ith a 10 d /ad (% =74-10)F initially se 790 &>52) Co/y C%$ dis/lay on the >P =794" Bor any C%$ dis/lay6 record *ain and /hase

se/arately6 if desired

8) %eset s,ee/ ,idth to 200 &>5 and co/y C%$ dis/lay

4) %eset s,ee/ ,idth to entire ran*e (4 Q 1800 &>5) and co/y C%$ dis/lay9) %e/lace 10 d /ad ,ith a lo,-/ass filter (% =74-B)

;) %eset Bre: to 900 &>5 or 1000 &>5 (as a//ro/riate)6 ,iden s,ee/ ,idth (try 900&>5)6 and ad@st Ch 1 and 2 reference levels to fit res/onses ,ithin C%$ dis/lay3eterine the filterXs corner fre:ency6 roll-off slo/e (ddec)6 and s+etch the C%$

dis/lay

7) %e/lace lo,-/ass filter ,ith a 20 c air line (% =74-#20) sin* a fre:ency of 790&>5 and co/y C%$ dis/lay Calclate e?/ected /hase shift and co/are to

easreent

=) %eset s,ee/ ,idth to entire ran*e (4 Q 1800 &>5) and co/y C%$ dis/lay Calclate

e?/ected /hase slo/e (de*&>5) and co/are to easreent

Part III %eflection &easreent Cali.ration of the >P =794" !et,or+ "naly5er

") >P =794" !et,or+ "naly5er Settin*s

1) Polar "% 3e/ress to o.tain /olar dis/lay2) Bre: select center

8) S,ee/ atofast6 +no. controls s,ee/ s/eed (trn cloc+,ise to dis/lay solid line)

4) Jideo Bilter trn off (liits .and,idth of s,ee/ fre:ency)

9) $nin* set to 790 &>5


23/51

;) S,ee/ Width set to 0

7) &ar+ers trn off (disa.led in /olar dis/lay)

=) 't/t d set to V 0 d to avoid satratin* the %6 "6 and in/tsP =794" to the Bl+e 7220" fre:ency conter andcali.rate the >P =794" fre:ency dis/lay6 if necessary

2) Connect the >P =794" to the >P =902" $est Set as follo,s

8) Set the %B In/t "ttenation +no. on the >P =902" $est Set to 0 d

Bi*re 2 Confi*ration for %eflection &easreent

>P =902"

$est Set

%B In

>P =794"

!et,or+ "naly5er

%%B 't "

%"

$estPort

3eviceUnder

$est

E:al#en*th

#ines

Incident

%eflected

3U$&&

BB

Y$hrXsZ


24/51

4) Connect a /air of feale-feale and ale-ale thrX ada/ters .et,een the % /ort on

the >P =902" and its ca.le $his ,ill co/ensate for the /hase delay cased .y the

distance .et,een the test /ort and the actal short /osition $he %B si*nal traversesthis distance t,ice once fro the test /ort to the short /osition and fro the short

/osition .ac+ to the test /ort (,here it effectively enters /ort ") >ence6 t,o thrX

ada/ters electrical len*ths are sed to co/ensate for the /hase easreents9) Connect a short (% =74-W!8) for the device nder test (3U$)

;) "d@st Ch 1 offset to o.tain a a*nitde of 1

7) "d@st Ch 1 line len*th to o.tain /hase of 1=0o &ay also re:ire an ad@stent ofthe Ch 2 reference ,heel se Ch 1 line len*th to fine tne

Part IJ %eflection &easreents

3iscssion on easreent /rocedre %ee.er that M(5) Mo(1 N (5)) (1 - (5)) is

the relationshi/ .et,een the reflection coefficient at a location (5) and the i/edance at

a location M(5) for a transission line ,ith 50 at the load and Mois the characteristic

i/edance of the transission line "lso ree.er that the .ondary condition at 506the /osition on the transission line ,hich ,e sed to cali.rate the net,or+ analy5er

,ith the short circit6 re:ires that M(0) M#since the volta*e and crrent are continosat 50 "lso note that Mo is the characteristic i/edance of the easreent syste6 ie6

the test set for the net,or+ analy5er6 ,hich is 90 ohs ecase (0) #6 then

M# Mo(1N #)(1-#)6 ,here Mois the 90 ohs of the test set

1) %e/lace short ,ith n+no,n load (% =74-& or =74-)F o/en the [can[ and record

the vale of the l/ed /araeter resistor sin* its color code

2) %ecord the vale (a*nitde and /hase) of the reflection coefficient for the n+no,nload6 ie6 (0)# Convert this reflection coefficient to its corres/ondin*

transission line i/edance at the location of the reflection coefficient6 M(0)F this

i/edance is the easreent of the actal load i/edance6 M#

8) %e/lace the n+no,n load ,ith a 90 terination (% =74-W90) and re/eat ste/

\2 a.ove 3iscss ,hat yo o.serve in this case for (0)#and M#


25/51


26/51

Bor transission lines 4 lon*6

Procedre

Part I reflection coefficient6 transission line i/edance6 and sith chart1) Choose an o/eratin* fre:ency .et,een 900 &>5 and =00 &>56 and cali.rate the

net,or+ analy5er (settin* the s,ee/ ,idth to 0) for reflection easreents .y

connectin* the >P =902" to the >P =794" as sho,n in Bi*re 2 of #a. \1 for reflectioneasreents and sin* the short circit for a load follo,in* Part III of #a. \1

2) Connect the n+no,n load and easre and record the reflection coefficient6 (#)direct6

and then se the sith chart to calclate the load i/edance6 (M#)direct

8) Insert the 20 c air line .et,een the n+no,n load and the test set6 and then easreand record the in/t reflection coefficient of the resltin* circit6 (#)20 c

4) Usin* the Sith Chart6 se a short for a load to estiate the electrical len*th of thetransission line6 len*th as easred in nits of ,avelen*th6 #H "nnotate the sithchart ,ith sfficient inforation so that a /eer ,ill nderstand yor /rocedre for

o.tainin* the electrical len*th fro a short circit load

9) Usin* the vale of yor in/t reflection coefficient (#)20 cand the len*th of theintervenin* transission line #H6 analytically calclate the load i/edance6

(M#)20 c analytical

;) Usin* the Sith Chart6 deterine the reflection coefficient of the n+no,n load

(#)20 c sithand /rovide an estiate of the n+no,n load i/edance6 (M#)20 c sithFannotate the sith chart ,ith sfficient inforation so that a /eer ,ill nderstand yor

/rocedre for o.tainin* the estiated load i/edance

Part II %eflection &easreents sin* 2 line

1) Connect the >P =902" to the >P =794" as sho,n in Bi*re 2 of #a. \1 for reflection

easreents Set s,ee/ ,idth to 02) Use the sae fre:ency chosen in Part I and cali.ration settin*s

8) Connect an [email protected] air line (% =74-#T10# or =74-#T20#) to the test /ort of the

>P =902"

M#

2

Min Lin ZZ =

M#

4

MinL

oin

Z

ZZ

2

=

Mo

Mo


27/51

4) $erinate the line ,ith a short (% =74-W!8) "d@st the len*th of the air line to

o.tain a Q1 dis/lay on the C%$ (ay re:ire additional fi?ed-len*th air lines) $his

sets the len*th to a lti/le of a half-,avelen*th

!ote the [email protected] lines have a loc+in* cla/ ,hich can .e sed to fi? the len*th

#oosen the cla/ for ad@stent and ti*hten ,hen the correct len*th has .een fond

9) %e/lace the short-circit terination ,ith the n+no,n load (% =74-& or =74-)

%ecord the reflection coefficient (/olar dis/lay6 a*nitde and /hase);) Convert the reflection coefficient into the actal load i/edance6 (M#)H2

"sse Mo 90

Part III %eflection &easreents sin* 4 line

1) %etainin* the sae fre:ency and cali.ration6 re/lace the n+no,n load ,ith an o/en

terination (% =74-W'8) "d@st the len*th of the air line to o.tain a Q1 dis/lay on

the C%$ (ay re:ire additional fi?ed-len*th air lines) $his sets the len*th to an oddlti/le of a :arter-,avelen*th

2) %e/lace the o/en ,ith the n+no,n load (% =74-& or =74-) and record the

/osition of the reflection coefficient (/olar dis/lay6 a*nitde and /hase)8) Convert the reflection coefficients o.tained into the actal load i/edance6 (M#)H4

"sse Mo 90 Co/are to the vale o.tained in Part II and e?/lain any

discre/ancies

Part IJ Pro/a*ation Jelocity

1) %e/lace the [email protected] air line ,ith a fi?ed-len*th 20 c line (% =74-#20) and

terinate the line ,ith a short (% =74-W!8)

2) "d@st the si*nal fre:ency of the >P =794" to o.tain a Q1 dis/lay on the C%$ $hissets the len*th of the line to 2

8) Co/te the /ro/a*ation velocity J/sin* the forla Vp= f Co/are to c

S**estion se the transission line set / in Part II ([email protected] air line /ls /ossi.ly

fi?ed air line to *et 2)6 and easre the len*th of the line fro the cali.ration /lane to

the short circit to estiate the len*th of 26 hence

!ote $he a.ove Part IJ /rocedre leads to a fre:ency that is different fro the onesed to cali.rated the net,or+ analy5er6 and hence can lead to vales of J/] cF this is a

*ood e?ercise for the stdents to a//reciate the liitations of the easreent /rocedre6

ie6 e?/lain the error

%e/ort Conclsion Co/are the estiate calclations of the n+no,n i/edance

(M#)20 c analytical6 (M#)20 c sith6 (M#)H26 and (M#)H46 ,ith the vale o.tained ,ith the direct

easreent (M#)direct6 F se a ta.le to sari5e yor reslts State /ossi.le sorces oferror for any differences "lso6 o/en the [can[ and record the vale of the l/ed

/araeter resistor (se the color code)6 and coent on ,hy the vale of M#is not the

vale of the resistor In addition6 coent on any error o.tained for the easreent ofJ/


28/51



EE 442 I/edance &easreent .y 2 and 4 #ines #a. 2

Prela.

%ead Section 718 of te?t

Pr/ose

$o se 2 and 4 lines as easreent aids and to verify transission line theory for

2 and 4 lines

%eferences

EE 402 $e?t &a*dy Is+ander6Electromagnetic Fields and Waves6 WavelandPress6 2000

>P =794" !et,or+ "naly5er '/eratin* &anal>P =902" $ransission%eflection $est Set '/eratin* &anal

E:i/ent

>P =794" !et,or+ "naly5er

>P =902" $ransission%eflection $est Set

Bl+e 7220" Bre:ency Conter

>P 11=91" %B Ca.le Tit% =74-W'8 '/en-Circit $erination

% =74-W!8 Short-Circit $erination

% =74-#20 20 c Bi?ed-#en*th "ir #ine% =74-#T10 10 c "[email protected] "ir #ine (89 c to 49 c)

% =74-#T20 20 c "[email protected] "ir #ine (;0 c to =0 c)

% =74-& or Un+no,n #oad (co/onent ont)Bittin*s "ccessories

$heory

&odifyin* e:ation (7;


29/51

Bor transission lines 4 lon*6

Part I %eflection &easreents sin* 2 line

7) Connect the >P =902" to the >P =794" as sho,n in Bi*re 2 of #a. \1 for reflection

easreents Set s,ee/ ,idth to 0

=) Choose an o/eratin* fre:ency .et,een 900 &>5 and =00 &>5 and cali.rate for

reflection easreents as /er Part III of #a. \1P =902"

10) $erinate the line ,ith a short (% =74-W!8) "d@st the len*th of the air line too.tain a Q1 dis/lay on the C%$ (ay re:ire additional fi?ed-len*th air lines) $his

sets the len*th to a lti/le of a half-,avelen*th

!ote the [email protected] lines have a loc+in* cla/ ,hich can .e sed to fi? the len*th

#oosen the cla/ for ad@stent and ti*hten ,hen the correct len*th has .een fond


%ecord the reflection coefficient (/olar dis/lay6 a*nitde and /hase)12) Convert the reflection coefficient into the actal load i/edance "sse Mo 90

Part II %eflection &easreents sin* 4 line

4) %e/lace the n+no,n load ,ith an o/en terination (% =74-W'8) "d@st the

len*th of the air line to o.tain a Q1 dis/lay on the C%$ (ay re:ire additional fi?ed-len*th air lines) $his sets the len*th to an odd lti/le of a :arter-,avelen*th

9) %e/lace the o/en ,ith the n+no,n load (% =74-& or =74-) and record the

/osition of the reflection coefficient (/olar dis/lay6 a*nitde and /hase);) Convert the reflection coefficients o.tained into the actal load i/edance "sse

Mo 90 Co/are to the vale o.tained in Part I and e?/lain any discre/ancies

Part III Pro/a*ation Jelocity

4) %e/lace the [email protected] air line ,ith a fi?ed-len*th 20 c line (% =74-#20) and

terinate the line ,ith a short (% =74-W!8)9) "d@st the si*nal fre:ency of the >P =794" to o.tain a Q1 dis/lay on the C%$ $his

sets the len*th of the line to 2

M#

4

MinL

o

in Z

ZZ

2

=

Mo


30/51

;) Co/te the /ro/a*ation velocity J/sin* the forla Vp= f Co/are to c


31/51



EE 442 $ransission #ine Paraeters #a. 8

Prela.

%ead Section 710 of te?t

Pr/ose

$o deterine the transission line /araeters for an %-=U ca.le

%eferences


>P =794" !et,or+ "naly5er '/eratin* &anal

>P =902" $ransission%eflection $est Set '/eratin* &anal

E:i/ent

>P =794" !et,or+ "naly5er >P =902" $ransission%eflection $est Set


>P 11=91" %B Ca.le Tit% =74-W'8 '/en-Circit $erination


%-=U Ca.le

Bittin*s "ccessoriesSith Charts

$heory

elo, is the re/resentation for the easreent circit ,ith the definition of the

varia.les sed in the analysis

5 -l (reference /lane) 5 0

Mo Mo

net,or+ analy5er lo, loss transission line load

end

V-] M Min(-l)


32/51

!ote that Mo 90 oh is the characteristic i/edance of the net,or+ analy5er6 and is

the easred reflection coefficient at the reference /lane deterined .y the cali.ration

/rocedre Min(-l) is the transission line i/edance at 5 -l and is e:al to M.ecaseof the .ondary conditions $herefore6 Min(-l) M Mo(1 N )(1 - ) $he

easreent calclations for the lo, loss transission line follo, the analysis .elo,

&odifyin* e:ation (7;=) in the te?t for lossy transission lines ( 0 )

( )

( )lZZ

lZZZlZ

Lo

oLoin

tanh

tanh)(

+

+= (1)

$he in/t i/edance of a transission line of len*th lterinated in a short-circit has

the vale

( )lZZ oshort

in tanh= (2)

Bor the sae line terinated in an o/en-circit6 the in/t i/edance is *iven .y

( )lZZ oopen

in coth= (8)

,here N @6 /ro/a*ation factor6 attenation factor (!/)6 /hase factor

(rad) &lti/lyin* e:ation (2) .y (8) yields6

open

in

short

ino ZZZ = (4)

3ividin* e:ation (2) .y (8) reslts in6

( )1

1tanh

2

2

+

==

l

l

open

in

short

in

e

e

Z

Zl

(9)

Solvin* for the e?/onential in (9)6

open

in

short

in

open

in

short

in

l

Z

Z

Z

Z

e

+

=

1

12

(;)

and ta+in* the natral lo*arith of .oth sides of (;) yields6


33/51

+

=+=

open

in

short

in

open

in

short

in

Z

Z

Z

Z

ljll

1

1

ln2

1 (7)

3efinin*

open

in

short

in

open

in

short

in

Z

Z

Z

Z

x

+

=

1

1

(=)

and solvin* for in (7) yields6

( )xlln

2

1= (P =902" to the >P =794" for reflection easreents as sho,n inBi*re 2 of #a. \1

2) Set the >P =794" to 89 &>5 and cali.rate for reflection easreents as /er Part III

of #a. \1

8) Connect one len*th of the %-=U ca.le (a.ot 1= in len*th) to the test /ort of the>P =902" $est SetF record the I3\ of the ca.le6 and se a rler to easre its

/hysical len*th

4) $erinate the ca.le ,ith a short (% =74-W!8) and record the reflection coefficient(/olar dis/lay)

9) 3eterine the vale nin e:ation (10)

a) %edce the fre:ency settin* on the >P =794" to 5ero (crsor shold .e close to

-1 ) "t 5ero fre:ency6 the electrical len*th of the ca.le is 0


34/51

.) Slo,ly increase the fre:ency / to the test fre:ency and note the n.er of fll

revoltions on the dis/lay $his is the vale n the electrical len*th of the ca.le at

the test fre:ency is nfll half-,avelen*ths;) %e/lace the short ,ith an o/en terination (% =74-W'8) and record the reflection

coefficient (/olar dis/lay)

7) Convert the reflection coefficients o.tained in ste/s \4 and \9 a.ove intoshort

inZ andopen

inZ sin* a Sith Chart !ote each calclated i/edance is Min(-l) for the

a//ro/riate load and that Mo 90

=) %e/eat ste/s \2 (cal only)6 and \8 thro*h \7 for a fre:ency of 1000 &>5

^o/tional =)_ %e/eat ste/s \2 (cal only)6 and \8 thro*h \; a.ove for a fre:encies of 900

&>5 thro*h 1000 &>5 in ste/s of 100 &>5 Bor ste/ \76 se a co/ter /ro*ra to

co/teshort

inZ andopen

inZ fro the easred reflection coefficients

Part II Co/tation of $ransission #ine Paraeters

1) Calclate Mo6 6 and for all fre:encies sin* e:ations (4)6 (


35/51

odel of .ehavior Usin* this conce/t6 a chec+ can .e ade on the calclations of the

transission line /araeters as follo,s

1 `89G `100010

2 R89G R100080

8 scGoc and (an*le of sc) N (an*le of sc) G (1=0 de*rees)od

4 (Mo)89 G (Mo)10009 (#6C)89G(#6C)1000

; (J/)89G(J/)1000


36/51



EE 442 Use of the Sith Chart for #ine-#en*th and #ine-#oss Corrections #a. 4

Prela.

%ead section 712 in te?t

Pr/ose

$o learn Sith Chart techni:es to correct for line-len*th and line-loss errors cased .y

transission lines

%eferences




E:i/ent



>P 11=91" %B Ca.le Tit

% =74-W!8 Short-Circit $erination% =74-& or Un+no,n #oad (co/onent ont)

%-=U Ca.le Use sae ca.le (\I3) as sed in #a. 8Bittin*s "ccessories

Sith Charts

Part I %eflection Coefficient &easreents

1) Connect the >P =902" to the >P =794" for reflection easreents as sho,n in

Bi*re 2 of #a. \12) Set the >P =794" to 89 &>5 and cali.rate for reflection easreents as /er Part III

of #a. \18) Connect the sae %-=U ca.le sed in #a. 8 (se the I3\ to deterine) to the test/ort of the >P =902" $est Set and terinate the ca.le ,ith a short (% =74-W!8)

%ecord the reflection coefficient (/olar dis/lay)

4) Plot the reflection coefficient on a Sith Chart and find the electrical len*th in

,avelen*ths and retrn loss of the ca.le in d9) %e/lace the short-circit terination ,ith the n+no,n load (% =74-& or =74-)

%ecord the reflection coefficient (/olar dis/lay)6 Nca.le


37/51

;) %eove the %-=U ca.le and connect the n+no,n load directly to the test /ort of

the >P =902" $est Set %ecord the reflection coefficient (/olar dis/lay)6 load

7) Plot the reflection coefficients o.tained fro ste/s \9 and \; on a Sith Chart "//ly

line-len*th and line-loss corrections to Nca.leand co/are to the actal reflection

coefficient6 load

=) Convert .oth the corrected and actal reflection coefficients into the load i/edancesM#(corrected)and M#(actal)6 res/ectively "sse Mo 90

5

Part II Conclsions

Co/are the /airs of vales for and M#co/ted at 89 &>5 and 1000 &>5

3eterine len*th and loss errors in and d6 res/ectively6 and coent on any

discre/ancies Present the reslts in a ta.le for .oth fre:encies "*ain6 note that the

/erforance of the transission line chan*es as the fre:ency increasesF discss thetransition fro a lossless odel to a lo,loss odel to e?/lain this chan*e in .ehavior


38/51



EE 442 $he Slotted #ine $echni:e in I/edance &easreents #a. 9

Prela.

%ead sections 719-1; in te?t

Pr/ose

$o learn the se of the slotted line in i/edance and SW% easreents

%eferences

EE 402 $e?t &a*dy Is+ander6Electromagnetic Fields and Waves6 Waveland

Press6 2000% =74-#" or # Slotted #ine '/eratin* &anal

>P 419 Standin* Wave Indicator '/eratin* &anal

E:i/ent

% =74-#" or # Slotted #ine

>P 419 Standin* Wave Indicator Bl+e ;0;0 %B Si*nal enerator


% =74-320 "[email protected] St. (2; c to 4; c)

% =74-& or Un+no,n #oad (co/onent ont)%-=U Ca.le

Bittin*s "ccessoriesSith Charts

Part I SW% &easreent Cali.ration of the % =74-#" or # Slotted #ine and >P

419 Standin* Wave Indicator

") >P 419 Standin* Wave Indicator Settin*s

1) In/t Selector set to tal6 200 +(this is the ty/e of detector sed on the slotted

line)2) %an*e 80 d /osition8) olo ias Crrent !" ,hen selector is set to tal

4) &eter Scale !oral (.lac+ scale) "llo,s easreent of SW% fro 1 to

(e?/anded scale only allo,s a a?i of 18 this is for /recision easreents on

,ell-atched lines)9) ain to .e ad@sted ,hile ta+in* easreents Initial settin* trn co/letely in the

cloc+,ise direction


39/51

;) Indicator sho,s detected /o,er (s:are-la, detector PEindicator 2

)

) Bl+e ;0;0 %B enerator Settin*s

1) Paraeter data entry /ress fnction +ey (ie Bre:6 "/l6 "&6 etc)6 enter vale6 then

/ress nit (ie &>5J6 d6 etc)2) Set Bre: to 900 &>56 "/l to 0 d6 and "& to 90b

8) Press I!$ "& and select 1000 >5 .y /ressin* the 4001000 +ey $he I!$ "& +ey

trns on the a/litde odlation fnction (internally tri**ered) $he "& settin*s/ecifies the dty cycle of the ,avefor

C) SW% Cali.ration and &easreent Procedre

1) Connect the Bl+e ;0;06 [email protected] st. (% =74-320)6 and short (% =74-W!8)

to the slotted line (% =74-#" or #) as follo,s

2) "d@st /ro.e /osition on the slotted line ntil the >P 419 detects a /ea+ $his ay

re:ire ad@stent of the st. (% =74-320) len*th

8) "d@st st. (% =74-320) len*th for a?i deflection on the >P 419 SW%eter Siltaneosly ad@st the *ain +no. to avoid /innin*X the SW% indicator

needle !ote the st. len*th ad@stent is very sensitive $he /ro/er len*th i/roves

the atch fro the slotted line to the /ro.e ,hich enhances /o,er transfer to the

SW% eter4) "d@st the *ain dial to o.tain a needle deflection at e?actly SW%1 Jerify that the

/ea+ has .een fond .y ovin* the /ro.e alon* the slotted line arond the /ea+

/osition and resettin* to SW%1 if necessary9) $o easre SW%6 ove the /ro.e to the ini /o,er /osition (left deflection)

and note SW% Bor a short-circit terination6 the SW% shold .e very hi*h

(theoretically infinity)

Part II Wavelen*th and #oad &easreent sin* the Slotted #ine

Bl+e ;0;0

%B Si*nal

enerator

Mo

% =74-#" or # Slotted #ine

% =74-320

"[email protected] St.

>P 419SW% &eter

#oad

Bi*re 8 Confi*ration for Slotted #ine &easreents

/ro.e


40/51

1) %ecord t,o ad@acent volta*e ini /ositions l1(nearest the load) and lin c on

the slotted line

2) %e/lace the short ,ith the n+no,n load (% =74-& or ) and easre the SW%!ote st recali.rate for SW% easreent (set to SW%1 at the /ea+ /o,er

/osition)

8) %ecord the /osition d1of the volta*e ini .et,eenl1and

l

4) %e/eat ste/s \1 thro*h \8 a.ove for fre:ency intervals of 90 &>5 to 700 &>5

Part III Co/tation of the Wavelen*th and #oad I/edance

1) Calclate the free-s/ace ,avelen*th in c for the fre:encies s/ecified in ste/ \4 of

Part II a.ove2) Calclate the distance .et,een t,o volta*e inis (l1and l) and co/are to the

e?/ected vale

8) Plot the SW% circle on a Sith Chart for each fre:ency tested

4) Co/te the distance .et,een the load and volta*e ini .et,een l1and l

/rodced .y the n+no,n load (l distance .et,een

l1and d1)9) e*innin* at the volta*e ini /oint on the SW% circle6 ove alon* the circle in

the W$# direction the distance lin to o.tain the reflection coefficient at the load

/lane "lternatively6 the distance .et,een land d1can .e sed in ,hich case the

oveent alon* the SW% circle shold .e in the W$ direction %e/eat for all

fre:encies

;) Convert the load /lane reflection coefficient to the actal load i/edance %e/eat forall fre:encies

7) &easre the load i/edance ,ith the net,or+ analy5er at all fre:encies for

co/arison /r/oses=) Co/are the calclated load i/edances to the vales easred .y the net,or+

analy5er at all fre:encies and discss reslts


41/51



EE 442 I/edance &atchin* .y the Sin*le-St. $nin* &ethod #a. ;

Prela.


Pr/ose

$o atch a load i/edance to a transission line sin* the sin*le-st. atchin*

techni:e

%eferences




E:i/ent




% =74-W!8 Short-Circit $erination% =74-W'8 '/en-Circit $erination

% =74-#10 10 c Bi?ed-#en*th "ir #ine% =74-#20 20 c Bi?ed-#en*th "ir #ine

% =74-#T10 10 c "[email protected] "ir #ine (89 c to 49 c)


% =74-320 "[email protected] St. (2; c to 4; c)% =74-& or Un+no,n #oad (co/onent ont)

Bittin*s "ccessories

Sith Charts

Part I %eflection &easreents and Sin*le-St. &atchin*


Bi*re 2 of #a. \1

2) Select a fre:ency .et,een 900 &>5 and =00 &>5 and cali.rate the >P =794" for

reflection easreents as /er Part III of #a. \1


42/51


and record reflection coefficient (/olar dis/lay) Use a Sith Chart to convert to load

i/edance4) Use a Sith Chart and the load i/edance inforation o.tained in the /revios ste/

to calclate the re:ired len*ths and locations of a sin*le short or o/en-circit

atchin* st. for .oth /ossi.le soltions Select reali5a.le confi*rations ,ithres/ect to the [email protected] and fi?ed len*th air line len*ths (see e:i/ent list a.ove)

9) Insert the st. lines terinated ,ith short (% =74-W!8) or o/en circit loads (%

=74-W'8) and series lines "d@st the st. len*th and location to the desi*n len*thscalclated in ste/ \4 a.ove for .oth soltions %ecord the retrn loss and JSW%

3eterine the .and,idth for .oth soltions ,ithin ,hich the retrn loss is *reater

than 10 d

Part II Conclsions

1) Sho, all details of the load i/edance deterination in ste/ \8 of Part I a.ove

2) Sho, all details of the sin*le-st. desi*n /rocedre descri.ed in ste/ \4 of Part Ia.ove Inclde Sith Chart dia*ras

8) 3iscss the retrn loss and JSW% for .oth soltions Was one desi*n .etter than theotherO WhyO

4) 3eterine ,hich of the t,o desi*ns yields the ,idest .and,idth and ,hy


43/51



EE 442 I/edance &atchin* .y the 3o.le-St. $nin* &ethod #a. 7

Prela.


Pr/ose

$o atch a load i/edance to a transission line sin* the do.le-st. atchin*

techni:e

%eferences




E:i/ent





% =74-#10 10 c Bi?ed-#en*th "ir #ine% =74-#20 20 c Bi?ed-#en*th "ir #ine

% =74-#T10 10 c "[email protected] "ir #ine (89 c to 49 c)




Sith Charts

Part I %eflection &easreents and 3o.le-St. &atchin*


Bi*re 2 of #a. \1

2) Select a fre:ency .et,een 900 &>5 and =00 &>5 and cali.rate the >P =794" for

reflection easreents as /er Part III of #a. \1

-


44/51


and record reflection coefficient (/olar dis/lay) Use a Sith Chart to convert to load

i/edance4) Use a Sith Chart and the load i/edance inforation o.tained in the /revios ste/

to calclate re:ired len*ths for a do.le-st. desi*n (.oth soltions) ,ith t,o st.s

terinated ,ith o/en-circit6 short-circit6 or a co.ination of o/en and short-circitloads "ccont for the distance .et,een the load and the first $ ada/ter Choose one

of the fi?ed-len*th or [email protected] air lines for the *1 circle rotation Select reali5a.le

confi*rations ,ith res/ect to allo,a.le air line len*ths (see e:i/ent list a.ove)9) Insert the st.s and ad@st .oth st. len*ths to the len*ths calclated in ste/ \4 a.ove

for .oth desi*ns %ecord the retrn loss and JSW% 3eterine the .and,idth for

.oth soltions ,ithin ,hich the retrn loss is *reater than 10 d

Part II Conclsions

1) Sho, all details of the load i/edance deterination in ste/ \8 of Part I a.ove

2) Sho, all details of the do.le-st. desi*n /rocedre descri.ed in ste/ \4 of Part Ia.ove Inclde Sith Chart dia*ras

8) 3iscss the retrn loss and JSW% for .oth soltions Was one desi*n .etter than theotherO WhyO

4) 3eterine ,hich of the t,o desi*ns yields the ,idest .and,idth and ,hy

-


45/51



EE 442 %evised #a. ; and 7 #a. 3

$he intent of these revised /rocedres is to co/lete la.s ; and 7 ,ith one re/ort in the three

hors of la.6 ie6 yo ,ill trn yor la. re/ort in at the end of the la. $he re/orts ,ill .e *raded

and retrned .efore the #a. Binal /eriod !ote that there ,ill .e la. tie allocated to/re/aration for the la. final and to co/letin* stdent evalations $he sith charts re:ired for

each of the desi*ns for the /rela. ,ill .e chec+ed at the .e*innin* of the la. &easreent of

distances is very i/ortant in the constrction of yor desi*ns6 and yo shold conslt ,ith the

instrctor if yo have :estions

Prela.

1 %ead #a. ; I/edance &atchin* .y the Sin*le-St. $nin* &ethod and #a. 7 I/edance

&atchin* .y the 3o.le-St. $nin* &ethod in yor EE 442 anal

2 %evie, section 7142 and e?a/le 714 in yor te?t for sin*le-st. atchin*

8 %evie, section 7148 and e?a/le 719 in yor te?t for do.le-st. atchin*

4 Bor the easred vale of yor load i/edance M#at ;00 &>5 (se the vale easred in #a.

\16 and chec+ load I3\ for easreents to verify desi*n)a) desi*n a sin*le-st. atchin* net,or+ for M#sin* a sith chartF annotate the sith chart ,ith

sfficient inforation so that a /eer can nderstand yor desi*n (inclde a dia*ra to define yorvaria.les) %efer to #a. ; for details

.) desi*n a do.le-st. atchin* net,or+ for M#sin* a sith chartF annotate the sith chart

,ith sfficient inforation so that a /eer can nderstand yor desi*n (inclde a dia*ra to define

yor varia.les) %efer to #a. 7 for details

%eferences

EE 402 $e?t &a*dy Is+ander6Electromagnetic Fields and Waves6 Waveland

Press6 2000

>P =794" !et,or+ "naly5er '/eratin* &anal>P =902" $ransission%eflection $est Set '/eratin* &anal

E:i/ent





% =74-#10 10 c Bi?ed-#en*th "ir #ine% =74-#20 20 c Bi?ed-#en*th "ir #ine% =74-#T10 10 c "[email protected] "ir #ine (89 c to 49 c)




Sith Charts

-


46/51

#a. Procedre

1 Jerify yor vale of M#,ith a easreent .efore .e*innin* (se ;00 &>5 as .efore) If the

easred vale has an error *reater than 9b fro the assed vale for yor desi*n6 then notify

the instrctor for frther instrctions

2 Constrct yor sin*le-st. desi*n a+in* sre to se an [email protected] airline to reali5e yordesi*n6 and then

a) easre its in/t ,ith the net,or+ analy5er.) calclate its JSW%

c) [tne[ yor desi*n .y ad@stin* the st. to *et the sallest vale of JSW%6 ie6 sallest vale

of retrn loss and record the corres/ondin* fre:ency6 ,hich is the center fre:ency f0

d) for the [tned desi*n[6 easre the -10d .and,idth6 ie6 the fre:ency a.ove and .elo, ;00

&>5 for ,hich the retrn loss is -10d6 f1and f2

3iscssion on easrin* -10d .and,idth %efer to the fi*re .elo, %ee.er that

JSW% (1N)(1-) and that 0 i/lies that (JSW%)in 1 ,hich in trn i/lies that

- d6 ie6 atched load conditions

e) insert a 10 c airline .et,een the load and the atchin* net,or+6 and tne the st. to *et thelo,est vale of JSW%6 and record it

8 Constrct the do.le-st. desi*n a+in* sre to se [email protected] airlines .et,een the load and

the st.s to reali5e yor desi*n6 and then

a) easre its in/t ,ith the net,or+ analy5er.) calclate its JSW%

c) [tne[ yor desi*n .y ad@stin* .oth st.s to *et the sallest vale of JSW%6 ie6 sallest

vale of retrn loss and record the corres/ondin* fre:ency6 ,hich is the center fre:ency f0

d) easre the -10d .and,idth of the [tned[ desi*n sin* the sae /rocedre sed for the

sin*le st. easreent to o.tain f1and f2

e) insert a 10 c airline .et,een the load and the atchin* net,or+6 and tne the st.s to *et the

lo,est vale of JSW%6 and record it

4 In yor conclsion6 discss the erits of each desi*n and /resent a ta.le that co/ares the t,o

[tned[ atchin* desi*ns ,ith res/ect to

a) tned load JSW% and .and,idth

.) tned 10 c ad@sted load JSW%

3ont for*et yor individal tho*htfl6 reflective /ara*ra/hs that discss ,hat yo have learned

-


47/51



EE 442 Introdction to Electrical Perforance "nalysis of Printed Circit oards #a. E

Pr/ose $his /ro@ect introdces the stdent to the analysis of the electrical /erforance of /rinted circit

.oards $his analysis ses the /rinci/les investi*ated in #a. "6 $ie 3oain "nalysis of $ransission

#ines6 and in #a. 6 Sinsoidal Steady-State "nalysis of $ransission #ines $he tie doain ste/res/onse and the fre:ency doain sinsoidal steady-state res/onse of the electrical /erforance of a

/rinted circit .oard can .e odeled sin* transission lines and l/ed /araeter eleents $his

investi*ation of ,ave /ro/a*ation on a /rinted circit .oard ses the sae techni:e sed in #a.s " and 6the se of lon* transission lines and ine?/ensive6 relatively lo, fre:ency instrentation to o.serve the

effects of tie (or /ro/a*ation) delay on the interconnect si*nal lines of a /rinted circit .oard $his

introdction stdies the /erforance of the connection of si*nal lines (traces) on a /rinted circit .oard6

,hich is elated .y the .ehavior of interconnected transission lines and l/ed /araeter eleents$he reslts ,ill .e discssed in the conte?t of the /erforance of /ractical circits oth the tie doain

ste/ res/onse and fre:ency doain sinsoidal steady-state res/onse are investi*ated in t,o ,ays sin* a

silation ,ith PS/ice6 and a easreent circit Bor each res/onse6 the reslts of each investi*ation

,ill .e co/ared

%eferences

EE 402 $e?t Is+ander6 &a*dy BF Electroa*netic Bields and WavesF Waveland PressF 2000

Cha/ter 76 es/ecially sections 71-56 then the ,avelen*th in free s/ace

,ill .e 10 c (a.ot 4 inches)6 and the actal ,avelen*th for the PC trace ,ill .e less - hence even oreco/ara.le to the actal diension of its len*th Within the chi/s6 the inte*rated circit ty/ically ,ill have

line ,idths6 and hence transistor and circit co/onent featres6 on the order of less than a icro6 ,hich isless than the ,avelen*th in the edia6 ie6 circit diension 10-; VV 10-1 ,avelen*th in edia (H)

$herefore6 ,ithin the chi/ l/ed /araeter circit eleents can .e sed to odel the circit .ehavioret,een the chi/s on the PC6 since the diension of the si*nal traces are on the order of the ,avelen*th

in the edia6 the distri.ted /araeter transission line odel can .e sed to analy5e circit .ehavior

In this la.6 the /rela. ,ill se PS/ice to silate the /erforance of a circit ,hich consists of .othl/ed /araeter and distri.ted /araeter eleents $here are t,o circits that ,ill .e stdied t,o

transission lines ,ith a /arallel connected 90 oh resistor .et,een the6 and a three transission lines

circit ,ith one transission line connected to t,o transission lines in /arallel (all the transission lines

-


48/51

have a characteristic i/edance of 90 ohs) "s ,ill .e o.served6 the .ehavior of the sorce sin*le

transission line and one of the /arallel atched /arallel transission lines can .e deterined .y re/lacin*

the other /arallel atched transission line ,ith a /arallel connected 90 oh resistor $his can ost easily

.e e?/lained .y the fact that .oth of the atched /arallel transission lines do not have a reflected ,ave!ote ho,ever that the sorce sin*le transission line does have a reflected ,ave6 and therefore does not

re/resent a atched load to the sorce Bor each circit stdied6 the ste/ res/onse and the sinsoidal steady

state res/onse are silated and analy5ed

Bi*re 1 Printed Circit oard E?a/le Circit


%evie, yor reslts of #a.s " and 6 /articlarly the /rela. PS/ice silation code &odify it

accordin*ly6 and se a transient analysis dration of 800 ns6 ,hich shold .e sfficient to o.serve the fll

ste/ res/onse .ehavior as ,ell as the co/lete sinsoidal res/onse (transient and the .e*innin* of thesinsoidal steady state res/onse) %efer to fi*re 2 Silate the ste/ res/onse and the sinsoidal

res/onse for each of the t,o circits /resented in fi*re 2 $he first case is the ste/ res/onse and the

second case is the sinsoidal res/onse $he terinatin* load for each case is 90 ohs6 ie6 atched

conditions for each transission line Each of the = % 9= "U lines can .e odel ,ith a characteristici/edance of 90 ohs and a tie delay of 40 ns

Bor the ste/ res/onse and for the sinsoidal res/onse for the circit in fi*re 2a/rovide a co/y of thePS/ice code and on one fi*re a co/y of the P%'E for J(2)6 J(8)6 and J(4)6 and for the circit in fi*re

2. a co/y of the PS/ice code and on one fi*re a co/y of the P%'E ot/t for J(2)6 J(8)6 J(4)6 andJ(9)6 Bor each case6 /rovide a one /ara*ra/h descri/tion of ,hy the ,avefor for J(2) has the sha/e

/resented in the silation "lso6 ans,er the follo,in* :estions

1 Why can the circit in fi*re 2a .e sed to odel the .ehavior of J(2) for the circit of fi*re 2.O

2 What is the avera*e /o,er delivered to each of the loads in fi*re 2.O !ote that the transission linesare lossless

8 Can the reflected ,ave in the sorce transission line .e reoved .y choosin* different terinatin*

loads on the t,o /arallel transission lines6 ie6 is it /ossi.le to atched the sorce ,ith t,o a//ro/riate

/arallel transission lines ,ith loadsO4 What ha//ens to the avera*e /o,er for the loads if ore than t,o atched /arallel transission lines

are connected to the sorce transission lineO !ote that a atchin* net,or+ at the @nction of the t,o

transission lines to the sorce transission line can .e sed to a?ii5e the /o,er to each load

-


49/51

Bi*re 2 $ransission #ine &easreent Circits


" #/ed Paraeter and $ransission #ines Circit (fi*re 2a)

a) Ste/ res/onse1 $he silation for a circit ,ith t,o transission lines connected ,ith a 90 oh resistor in /arallel

.et,een the ,ill no, .e verified ,ith easreents efore constrctin* the l/ed /araeter and

transission lines circit *iven in Bi*re 2a6 connect the first !C $ee to the sco/e channel 1 connection

so that J(2) ,ill .e sed as the channel 1 in/t and tri**er Connect the .anana load ,ith 90 oh resistordirectly to the first $ee ,ithot any transission line6 and o.serve the volta*e J(2) for an in/t volta*e of 1

&>5 s:are ,ave ,ith 10 J// and N900J 3C offset Use the oscillosco/e featres to ca/tre the

dis/lay of the volta*e J(2) for yor re/ort

2 Constrct the circit sho,n in Bi*re 2a sin* a atched load of 90 ohsF se t,o !C tees at the

connection .et,een the t,o transission lines6 one for addin* the 90 oh resistor in the connection

.et,een the t,o transission lines6 and the other one to easre J(8) on channel 2 of the sco/e Use

another !C tee to connect the 90 oh load6 and to /rovide access to J(4) to .e easred on channel 2 of

the sco/e Usin* the sae in/t volta*e6 o.serve the volta*es J(2)6 J(8) and J(4) (note that either J(8) orJ(4) can .e easred at one tie) Ca/tre the dis/lays of the volta*es J(2)6 J(8) and J(4) fro the

oscillosco/e for yor re/ort

8 Co/are the ste/ res/onse reslts of the silation and easreentF ho, close are theyO


the reflected (ne*ative *oin*) ,ave in the second transission line is 5ero >o,ever6 the volta*e at theload is not e:al to the initial /ositive ,ave in the first (sorce) transission line de to the /arallel 90 oh

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resistor $herefore6 there is a reflected ,ave at the sorce If the reflected ,ave is lar*e eno*h and of the

correct si*n6 then the lo*ic vale at the sorce end cold .e co/leented

.) Sinsoidal res/onse

1 Usin* the sae circit (fi*re 2a)6 disconnect the transission lines and connect the .anana load ,ith 90oh resistor directly to the first $ee (no transission line)6 and o.serve the volta*e J(2) for an in/t

volta*e of 10 &>5 sinsoidal ,ave ,ith a 10 J/ea+ Use the oscillosco/e featres to ca/tre the dis/lay

of the volta*e J(2) for yor re/ort

2 3isconnect the 90 oh .anana resistor6 and reconnect the transission lines Usin* the sae in/t

volta*e6 o.serve the volta*es J(2)6 J(8) and J(4) (note that either J(8) or J(4) can .e easred at one

tie) Ca/tre the dis/lays of the volta*es J(2)6 J(8) and J(4) fro the oscillosco/e for yor re/ort

8 Co/are the sinsoidal res/onse reslts of the silation and easreentF ho, close are theyO

3iscssion "*ain6 the second transission line is atched ,ith no reflected ,ave6 .t the steady state

a/litde is decreased If the in/t si*nal ,as a cloc+ si*nal6 then there ,old .e t,o effects cased .ythis circit tie delay (cloc+ s+e,) and a decrease in load (cloc+) volta*e

&lti/le transission lines circit and loadin* (fi*re 2.)

a) Ste/ res/onse

1 $he silation for a circit ,ith one transission line loaded ,ith t,o atched transission linesconnected in /arallel ,ill no, .e verified ,ith easreents efore constrctin* the lti/le

transission lines circit *iven in Bi*re 2.6 connect the first !C $ee to the sco/e channel 1 connection

so that J(2) ,ill .e sed as the channel 1 in/t and tri**er Connect the .anana load ,ith 90 oh resistordirectly to the first $ee ,ithot any transission line6 and o.serve the volta*e J(2) for an in/t volta*e of 1

&>5 s:are ,ave ,ith 10 J// and N900J 3C offset Use the oscillosco/e featres to ca/tre the

dis/lay of the volta*e J(2) for yor re/ort

2 Constrct the circit sho,n in Bi*re 2. sin* atchin* loads of 90 ohsF se t,o !C tees at the end

of the sorce transission line6 one for connectin* the t,o /arallel load transission lines6 and the other

one to easre J(8) on channel 2 of the sco/e Use the .arrels to connect the 90 oh loads ,ith one of the

!C tees to /rovide access to J(4) or J(9) as the sitation re:ires for its easreent on channel 2 of thesco/e Usin* the sae in/t volta*e6 o.serve the volta*es J(2)6 J(8)6 J(4)6 and J(9) (note that either

J(8)6 J(4)6 or J(9) can .e easred at one tie) Ca/tre the dis/lays of the volta*es J(2)6 J(8)6 J(4)6and J(9) fro the oscillosco/e for yor re/ort !ote that if yo o.serve no easra.le difference .et,een

J(4) and J(9)6 then yo can state soethin* li+e Ydifference .et,een J(4) and J(9) less than 9 JZstatin* yor estiate of the a?i volta*e differenceF this estiate vale shold not .e discerna.le in

the ca/tred dis/lay6 ie6 one dis/lay can re/resent .oth volta*es

8 Co/are the ste/ res/onse reslts of the silation and easreentF ho, close are theyO


the reflected (ne*ative *oin*) ,ave in the t,o load end transission lines is 5ero >o,ever6 the volta*e at

the either of the loads is not e:al to the initial /ositive ,ave in the first (sorce) transission line de tothe loadin* of the /arallel atched transission lines Brther6 the reslts at the sorce J(2)6 the

connection J(8)6 and each load J(4) or J(9) is the sae as the reslts ,ith Part " $his eans that the

circit can .e analy5ed .y re/lacin* one of the /arallel atched transission lines .y an e:ivalent circitof a 90 oh l/ed /araeter eleent ,ith res/ect to the vales of the other sorce volta*e J(2)6connectin* volta*e J(8)6 and either of the load volta*es J(4) or J(9) $his is an i/ortant o.servation for

si/lifyin* the analysis of a PC ,hich has lti/le /arallel si*nal trances

Sinsoidal res/onse

1 Usin* the sae circit (fi*re 2.)6 disconnect the transission lines and connect the .anana load ,ith 90

oh resistor directly to the first $ee ,ithot any transission line6 and o.serve the volta*e J(2) for an

in/t volta*e of 10 &>5 sinsoidal ,ave ,ith a 10 J/ea+ Ca/tre a dis/lay of the volta*e J(2)

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2 3isconnect the 90 oh .anana resistor6 and reconnect the transission lines Usin* the sae in/t

volta*e6 o.serve the volta*es J(2)6 J(8)6 J(4)6 and J(9) (note that either J(8)6 J(4)6 or J(9) can .e

easred at one tie) Provide dis/lays of the volta*es J(2)6 J(8)6 J(4) and J(9)

8 Co/are the sinsoidal res/onse reslts of the silation and easreentF ho, close are theyO

3iscssion $he sae o.servation ,ith res/ect to e:ivalent circits for the atched transission lines

a//lies to the sinsoidal case "s for the ste/ res/onse6 each of the load transission lines is atched ,ithno reflected ,ave6 .t the steady state a/litde of the load is decreased If the in/t si*nal ,as a cloc+

si*nal6 then there ,old .e t,o effects cased .y this circit tie delay (cloc+ s+e,) and a decrease in

load (cloc+) volta*e With ore cloc+ si*nal traces ,ith loads e:al to the sorce i/edance (90 ohs)6

there ,old .e ore /rononced decreases in the load volta*e6 ie6 less cloc+ /o,er delivered $hese t,o/henoena are a .i* isse in the desi*n of lar*e synchronos di*ital chi/s sch as BP"s

Conclsions

1) 3iscss the overall co/arison of the silation reslts and the easred reslts2) 3iscss the se of l/ed /araeter e:ivalent circits for atched transission lines6 and its

a//lica.ility to the analysis of PC circit .ehavior

3onXt for*et the individal tho*htfl6 reflective /ara*ra/h fro each la. *ro/ e.er at the end of yor

re/ort

Documents

442 Revised Lab Manual w07