Exam 2 Solved - Fall 2002 - Microelectronic Circuits | ECE 3040, Exams of Electrical and Electronics Engineering

Download Exam 2 Solved - Fall 2002 - Microelectronic Circuits | ECE 3040 and more Exams Electrical and Electronics Engineering in PDF only on Docsity! ECE 3040 Microelectronic Circuits Exam 2 Vaye t, The leng¢ A July 2, 2002 nf hig CXaar Dr. W.Alan Doolittle v5 aA) uste tor the Summor— Semesrer (lhe mn) Print your name ¢learly and largely: So | u } i 0 A $ Instructions: Read all the problems carefully and thoroughly before you begin working. You are allowed to use 1 new sheet of notes (1 page front and back), your note sheet from the previous exam as well as a calculator. There are 100 total points in this exam. Observe the point value of each problem and allocate your time accordingly. SHOW ALL WORK AND CIRCLE YOUR FINAL ANSWER WITH THE PROPER UNITS INDICATED. Write legibly. If I can not Tead it, it will be considered to be a wrong answer. Do all work on the paper provided. Tum in all scratch paper, even if it did not lead to an answer. Report any and all ethics violations to the instructor. Good luck! Sign your name on ONE of the two following cases: I DID NOT observe any ethical violations during this exam: J observed an ethical violation during this exam: Number of Exams Average=51.1 Std. Dev.=19.7 Maximum=37 Minimum=21 20 40 Test Score 60 80 100 Based on” Dopins A= (000 em ey Cmirter- t= 100n5 | | Adem No= le |8 m3 Depletion Resian ba 5 aK Moe te iF eur? $00 Collectar M paranerers A bn nt Given De = FO sane 0.0059 (1000)= 25.4 ehee - 4! De = % ease > 0.085% Caso) ~ 648 em Vsec Le- ¥ De te = J a54 (10068) = C.O5 08° cur O° F084 um By = Pole Ne 6.48 (9.05064) 1618 Dz W Ne ana (Sef) ey 2546 pr RXprz we _ ashe - 7e Bot! ~ S556 = 9:96 Can Increase mabilixy or t's base fo . Since Poe = Dg le Me 7 Can raise Emiyter Vaeping De W Mg —__= Can Lower Lage oaping ZA —__» lan Sha'nk base weil, can tilt mobility or Bin emitter mB W bus Cp = xD 15 the base ranger 8 t/me T hus our analy 3 choice $ t F\ are to Increase Ag ce or © pase yo. increase Ve, oc clecrease U% ( Bese Guar neutre l with) - Moves S/nce lowering Me lowers base due 40 dle creaseel hon Bec impurity Scar terihs lowering Mp Wad acceprect ages we Ul. (4" Section - 40%) Pulling all the concepts together for a useful purpose: 10.) (40-points) Given the following amplifier circuit and BJT Parameters, what is the AC voltage gain, Vout/Vac? Assume: Bpc=100, Early voltage is infinite, and the turn on voltages for all forward biased junctions are 0.7 V. You may assume all capacitors are very large values and are thus, AC shorts and any inductors are very large values, and thus AC opens. Additionally consider the circuit to be operated at low frequencies where you can neglect all small signal capacitances. Also, neglect all resistances that result from quasi-neutral regions. For full Credit, be sure to check your assumptions on the mode of operation of the transistor. Hint: Use the CVD/Beta analysis for the DC solution. Then apply your results to convert to the small signal model for both the BJT and diode (i.e. do not ignore the small signal model of the diode). . : Ri Re +| Vde 15K so = Vout Extra work space. Show your work clearly and label which problem this page contains. ; BIT Ac Sy lution : L —> 0 =Dape Baa a —eapey (Te gn One 179,49 Re C =? 08 wr shorty Ge Va+ Vee o= ——s ~. Drehe_ loc ~> in Te Te PR + 7 Vr Von > 340° me De thn “a CAz at = A: P9454 son 4 Tes age 0556 1 Xe Sigua = 90 se Thevenire hage erVeu 1m Carrer, di ery Re LL 0 Ure” Re Rone! Ca fe RAR D arsut > is (Re fRanae) > ~gm war (Blac) 4o= = QO Vi, = 4 oe geyra 44, lle = [@oee ¥en 4 Wsllra] 2s se ENE NE). > Const on heyy Page @ Extra work space. Show your work clearly and label which problem this page contains. @ rol @ ] Vac = oell ue) 00 a +101 (50) + ean [ei : eux The, z- 3/7 VV 0 6) aus (Re Nenu) (@)) teaver wera i ee a