Electronics Engineering Questions -Difficult

ELECTRONICS ENGINEERING DIFFICULT QUESTION 1.

How How many many SCRs SCRs are are req requi uired red in a ser serie ies s sri srin! n! o wi" wi"s san and d a DC #o$a!e o% &'(( #o$s in seady sae) i% "e SCRS "a#e seady sae #o$a!e rain! o% 1(((* and seady sae derain! %a+or o% &(,- ssumin! a di%%eren+e in $ea/a!e +urren o% SCR0s o e 1( m) +a$+u$ae "e #a$ue o% #o$a!e s"arin! resisan+es o e used. NS2ER3

4.

I was a erm +oined in 1561 y +ir+ui "eoris Leon C"ua as C"ua as a missin! non7$inear 8assi#e wo7ermina$ e$e+ri+a$ +om8onen re$ain! +om8onen re$ain! e$e+ri+ +"ar!e and +"ar!e and ma!nei+ %$u9 $in/a!e. $in/a!e. I is asi+a$$y a %our" +$ass o% e$e+ri+a$ +ir+ui) :oinin! "e resisor) "e +a8a+ior) and "e indu+or) "a e9"ii "eir unique 8ro8eries 8rimari$y a "e nanos+a$e. NS2ER3

&.

;E;RISTOR

T"is T"is y8e y8e o% memo memory ry is asi asi+a$ +a$$y $y an arra arran! n!em emen en o% s"i% s"i%  re!isers. I is used in a88$i+aions w"ere wo sysems +ommuni+ae a di%%eren raes.

NS2ER3

=.

'

FIFO or FIRST IN < FIRST OUT

I is is "e "e %as %ases es  swi swi+" +"in in! ! s8ee s8eeds ds +om +om8a 8are red d o any any $o!i $o!i+ + IC0s IC0s. . I +onsumes more 8ower "an TTL and e$iminaes "e urn7o%% de$ay. In8u $o!i+ $e#e$s are $imied o a narrow #o$a!e ran!e o redu+e "e $ar!e 8ower dissi8aion resu$in! %rom "e a+i#e mode. Deermine "e y8e o% +urren mode $o!i+ %ami$y.

NS2ER3

ECL or Emier Cou8$ed Lo!i+

'.

Find "e a#era!e dri% #e$o+iy in a si$i+on semi+ondu+or do8ed wi" 8"os8"orus. ssume do8in! densiy o% 1 8er mi$$ion) a +ross7se+iona$ area o% 1(7= m4) a +urren o% = ) and "e +on+enraion o% si$i+on aoms in a si$i+on +rysa$ is nsi > =.5? 9 1(4@ aomsAm&.

NS2ER3

?.

' mAs

Gi#e "e +ommon name %or w"a was $aer sandardiBed as "e IEEE 11=5.1 or "e Sandard Tes ++ess or and oundary7S+an r+"ie+ure. I was iniia$$y de#ised %or esin! 8rined +ir+ui oards usin! oundary s+an and is wide$y used %or "is a88$i+aion.

NS2ER3

6.

TG OT OINT TEST CTION GROU

2"a ne %$u9 +rosses "e +$osed sur%a+e S w"i+" +onains a +"ar!e disriuion in "e %orm o% a 8$ane dis/ o% radius =m wi" a densiy

 Ρ s=

NS2ER3

( sin ∅ ) 2r

2

( )

4 C

C 

m

2

@.

Find "e ou8u #o$a!e

NS2ER3

5.

==4 m*

In "e +ir+ui s"own e$ow) "e ou8us 1 and 4 %or "e !i#en iniia$ +ondiion 1 > 4 > 1 and a%er %our in8u 8u$ses wi$$ e

9 NS2ER3

1>1) 4>1

1(.

 "ree78"ase "a$%7+onro$$ed "yrisor +on#erer "as an "i!"$y indu+i#e $oad o% 1( o"ms) and a su88$y o% 4=(* a '(HB. Deermine "e #a$ue o% "e 8ower %a+or %or %irin! an!$e de$ay o% a > &(O.

NS2ER3

(.'@'

11. Deermine "e %requen+y o% os+i$$aion o% a 8"ase s"i% os+i$$aor wi" R1 > R4 > 1' / and C1 > C4 > C& > (.((1 F.

NS2ER3 14.

=.&& /HB

I is "e 8rodu+ion o% an e$e+romoi#e %or+e Jem%K and +onsequen$y an e$e+ri+ +urren in a $oo8 o% maeria$ +onsisin! o% a $eas wo dissimi$ar +ondu+ors w"en wo :un+ions are mainained a di%%eren em8eraures. NS2ER3

1&.

SEEEC EFFECT

Find E

a J1) 1)

1K +aused

y %our

ideni+a$

&

nC

8oin +"ar!es $o+aed a 1J1) 1) (K) 4J7 1) 1) (K) &J7 1) 7 1) (K =J1) 7 1) (K. NS2ER3

1=. 

"ree

?.@4ax  M ?.@4ay  M &4.@5az *Am i

8seudo

random

numer

!eneraor

is

s"own.

Iniia$$y "e #a$ue o% ou8u  > 4 1 ( is se o 111. T"e #a$ue o% ou8u  a%er "ree +$o+/ +y+$es is

NS2ER3

1((