{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

MidTerm 2B Winter 2010 solns

MidTerm 2B Winter 2010 solns - ECE ZB Mid-Term Exam Winter...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 10
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ECE ZB Mid-Term Exam Winter 2010 Mid-Term EXAM (”>0 I ocl’tawg Name: You have 75 minutes to complete this exam. Two pages of notes are allowed, otherwise there should be no books or other materials in your purview. You may use a calculator if necessary. When you are finished, check that your name appears prominently and legibly on the front page. The exam is worth 100 points total. IMPORTANT POINTS FOR GRADING: SHOW ALL WORK. ANSWERS GIVEN WITHOUT CLEAR SUPPORTING EVIDENCE OF INDEPENDENT WORK WILL BE IGNORED. CIRCLE ANSWERS OR WRITE THEM IN THE DESIGNATED SPACES. THOSE NOT CLEARLY MARKED AS YOUR FINAL ANSWER WILL BE IGNORED. BE NEAT. ILLEGIBLE OR SLOPPY WORK WILL BE IGNORED. The Stone Age was marked by man's clever use of crude tools; The Information Age, to date, has been marked by man's crude use of clever tools. Anonymous Page 1 of10 ECE 2B Mid-Term Exam Winter 2010 Problem 1 (15 points total, 5 points for each part) Unless otherwise specified, you can assume the diodes have a 0.7V drop under forward bias. SHOW YOUR WORK: unjustified answers will be disregarded. 270 Q a) For the zener biasing circuit at right, find the output voltage V and the diode current I : I 0 mA V =2g V f 6~Eg . :51 Q70 3.3V Zener (1N746A) [Sit/WI} b) For the circuit at right, find the output voltage V; and the diode current I : III e) For the circuit at right, find the output voltage V0", and the diode current I : Page 2 of 10 ECE 2B Mid-Term Exam Winter 2010 Problem 2 (20 points) A circuit has the following s-domain output voltage 4(s +1)2 V0", (S) : s(s + 2)(s2 + 2s + 2) Find the step response of the circuit, vom(t). A table of Laplace transforms is found at the end of this exam. , I 7 . - __, ”o x’ 07‘ 5 C a ’- '-i ’- gpr/w “C(ZLcjkf/V‘ WMMSIUM , A ‘ / A , data-L33 '2 j+ Page 3 of 10 ECE 2B Mid-Term Exam Winter 2010 Problem 3 (15 points) In the circuit below, the switch is closed for t<0 and the circuit is in the steady state. Suddenly the switch is opened at t = 0. t=0 19 Page 4 of 10 ECE 2B Mid-Term Exam Winter 2010 Problem 4 (20 points) In this circuit the switch has been closed for a long time, such that the circuit is in a steady state. Suddenly the switch is opened at t: 0. c) Find the output volt:g:nthe S'domain’ ,Vi’”(s) 2 3/25 I} \lMt/SV ; ”"i A W ”2:;t {97/53 7, (9413 S i :5 / 5;? t ‘31 (Continued on next page...) Page 5 oflO ECE 2B Mid-Term Exam Winter 2010 ( ............. problem 4, continued from previous page.) d) Find the output voltage van, (t) for t> 0 e) Is this an over-damped, under-damped,Q/critically-damped response? Page 6 of 10 ECE 2B Mid-Term Exam Winter 2010 Problem 5 (20 points total) In the circuits below, each device is an enhancement-mode NMOS FET with V; 21V and K" =1 mA/VZ. The constant Kn is defined as in lecture such that K" (ng — V,)2 Saturation (Vgs 2 V,, Vds > VgS — V,) D Kn[2(VgS—V,)Vds—Vd§] Ohmic (0<Vds ngS—K) SHOW YOUR WORK: unjustified answers will be disregarded. +5 V a) (5 pts) For the bias conditions shown at right, determine the region of Vg—IV operation (saturation or ohmic) and then find the drain current Id i Id /. x 5 LI // Saturation 9r Ohmic? (circle one) Id = 7 mA if k__,/ / ., \ 3 v1 — \ffs;(’/l\+{f$ / in I .1 -5V : L1 V :1; ;l./Z.(Vfi§’vé/B <> fl ”V [A +5 V b) (5 pts) For the circuit shown at right, findV V0", . If)", = w E V _I:_| ? V time :7 lé—t/Vii's’ V63 3 — [i7 Vag :— EV 4mA Vivi; ”EV +10 V c) (10 pts) For the circuit shown at right, find the required source and drain resistances RS and RD that will make Id =1mA and V =6V: 3M!) 0” ‘— .Vout Ré— 2k Q RD— Mk Q s _ A W %.f Id 7 \Mzfi f1) 13(25 Page 7 of 10 ECE 2B Mid-Term Exam Winter 2010 Problem 6 (10 points) The circuit below uses a MOSFET whose I-V characteristic are shown. é Vds, Volts fly/LA 6/ Draw the load-line for this circuit on top of the graph, and circle the appropriate intersection. What is the output voltage and drain current predicted by your load-line analysis? § {“l V = V Id = mA 0!” Page 8 of 10 ECE 2B Mid-Term Exam Table of Laplace Transform Pairs Winter 2010 Page 9 of 10 Signal Waveform f (t) Transform F (s) 1 Impulse 5U) 1 l 2 Step u(t) _ s 3 Ramp tu(t) :2 s tn~l 1 4 Power oft u(t) n = 1,2,3... _ (n — 1)! Sn 5 Exponential e‘a’ u(t) 1 _ s + a l 6 Da ed a t C" t mp r mp e u() (“(1)2 n—l 1 7 Damped Power I e—atu(t) n 21,233.” n oft (n—w <s+a> 8 Sine sin fit u(t) fl s2 + fi2 s 9 C ' cos t u t osme ,8 < > 32 + ’32 10 Sinusoid Vaz + b2 cosEfit—tan‘l é]u(t) a:+ bZ’B a s + fi 11 Damped Sine [at sin fit u(t) fl (s + (2)2 + ,82 12 Dam ed Cosine 6—6" cos fit (t) S + a u p (s + (2)2 + ,82 k k‘ -at + It Damped 2|k|e cos(fit + 4k)u(t) (s —p) (s —p ) 13 Sinusoid where P = —05 + LB (Complex Poles) 2 2 wt 4 b a(s+a)+bfi V a + b e cos fit — tan — u(t) —22 a (s + a) + fi k + k‘ Double Complex _a, _ 2 . 2 14 Poles 2|k|e tcos(fit + 1k)u(t) (S p) (s — p ) where p = —a + jfi ECE 2B Mid-Term Exam Winter 2010 Initial Conditions in the s-domain l [(3) +J— + SC C V _ V(S) fl‘ (f) “(0) var) — s Capacitor has an i 1 v(0_) impedance: SC 1(s) 2 SC V(s) — Cv(0_) V(s) = —I(s) + SC s l 1(5) + 1(3) + sL + éL m) i(0_) V(s) _ _ s Li(0“) Inductor has an L 1 . 0_ _ impedance: S [(s) : _Z V(s) + l( ) V(s) = sL[(s) — Li(0_) S S Page 10 of 10 ...
View Full Document

{[ snackBarMessage ]}