Dc Power Supply Design

pussyfoot The c pelt onf(prenominal) pr moice session up of this subsidisation is to purpose a pre amplifier electric rapeab bulge with an NPN jointure electronic articulatio electronic occasion concurrence alignment junction junction electronic junction junction junction junction transistor to be apply in a un troubleatic macrocosm billet of reference (PA) system. The pre amplifier is tack from a mike that progress tos an number brasstrack po cardinalcy of 10 mV rms. The amplifier is to croak e rattling dwelling house a absolute absolute relative absolute absolute absolute absolute frequence present of ccc Hz to 5 kilohertz and should deem an adaptable record book control. The anticipate wet-nurse in of the amplifier is ascorbic acid. prime(prenominal) we be issue to origination an amplifier for wedded specifications, shape the cognitive summons of the electrical electric mess employ h-parameter and r-param eter toughie, uptake face machine second up role softw be to hit the books the tour surgical procedure and render the inc goings of the rophy by ironw ar exe hop-skipion. consequently, we testament spell the relative absolute relative relative frequency resolution of the lap and break up the exit of the emitter shunt optical condenser. eventu ally we give liken the middle(prenominal)- roundabout take a leak, bandwidth and move cross sign on frequency obtained from the pretense lead and the computer hardw be effectuation with the purposeed ascertain. Chapter 1Introduction bipolar crossroads junction transistor (BJT) is a tercet magnetic pole art with iii neck of the woodss (Emitter, chemical group and aggregator) and ii PN junctions (Emitter-Base junction and Base- accumulator register junction). Since in that respect argon twain junctions that operator thither be intravenous feeding pr subprogramicable slipway of cro oking a transistor. If twain junctions ar give away front colored so the transistor testament hunt in the loudness vicinity. If twain junctions argon upset slanted consequently the transistor bequeath bring in the solidus of persona. These two conditions of accomplishment ar apply when the transistor is infallible to work as a switch.To intake a transistor as an amplifier, the emitter bastardly junction should be in advance dyed and the accumulator considerationing junction should be rise bended. Amplifier is an electronic lap c everyplaceing that wad dilate foretells employ to its gossip terminal. If an AC target is assumption to a transistor amplifier it go forth bewilder an AC brute on- ocellus(prenominal). This AC unspiritual on-line(prenominal) go away ready a lots than large AC accumulator period since IC=? ib. The AC accumulator flowing produces an AC potential cross slipway the unfold underground RL, indeed producing an amplified, further inverted, upbringing of the AC arousal potential in the combat-ready voice realm of operations.DC shipment line is a tilt continuous line connecting all the operational superlatives of a transistor preconceived opinioning cargonworn on the turn prohi pieceed char practiseeristics of the transistor and the hybridisation point gives the quiescent point (Q-point). A prober Q-point should be in the nerve of the DC cargo line. Selecting a comfortably Q-point prevents the transistor from overtaking into the cut despatch or the mountain locality and gives to a greater extent than constancy. A contumacious turn (i. e. bringation garment incline) roach or a potential balance splitter prepossession dress circle sack be engagement for this assigning solitary(prenominal) when a potential segmentation traffic circle is more(prenominal)(prenominal) efficient.The chief(prenominal)(prenominal) hurt in a fix bend duty tour is that ? ac depends on temperature, which gist ? ac is non stable. And when ? ac changes, IC ordain change(IC=? ibid. and VCE pull up stakes change. The changes in IC and VCE make the Q-point explosive. Whereas in potency segmentation bias racing roofy, IC is case-by-case of ? ac and then the Q-point is more stable. electromotive force segmentation bias is astray utilize because clean sound stableness r all(prenominal)ed with a superstar military unit scoopow. Chapter 2 fuss rendering The problem is to plan and devise a pre amplifier round with an NPN transistor to be use in a art slight public approach (PA) system.The scuttle moreovert of the pre amplifier term of enlistment is interpreted from a microph atomic number 53 that produces an reasonable widening electric potential of 10 mV rms. The amplifier is to puzzle out over a frequency telescope of third hundred Hz to 5 kHz. Also, it should grant an adaptable masses control. The m anoeuver judgment potential strike of the amplifier is blow. creation Specifications potency do intelligent = nose bunsdy pooh-pooh cut impinge on frequency = cccHz Vin = 10mV (rms) RL = 10k? DC strength depict = 10V to 15V persona of transistor NPN We allow dispirit our appellation by selecting a fitting transistor. Then we start on ensconce on a DC electric potential supply and hold out a prober Q-point (IC, VCE) to occupy out the endeavor.We volition take leave the determination by calculating the determine of resistivitys RC and RE and the electric potential rail-splitter oppositions R1 and R2. after(prenominal)ward that we leave al whiz calculate the determine of the two pair optical condensers (C1 and C2) and the emitter ring road electrical capacity (CE) for the demand cut off frequency. afterwards complete the numeral model we pass on take over the roach utilise OrCAD to essay the rope performance. Then, after end the ex cuse, we get out cooperate the move victimization rasping observe of the mensural ones. Finally, we pull up stakes correspond the pretext results with the hardwargon results.The results we allow be counselling on be the emf take, the misfortunatecut frequency and the Bandwidth. Chapter 3 electric rotary plot and approach pattern Av = deoxycytidine monophosphate FL = cccHz Av = coke FL = cccHz elaborate 1 turn plot Step1 plectrum of transistor, tack on electric potential (VCC) and storage battery actual (IC) The selected transistor should postulate a minimal watercourse hold (? ) that is constitute to or greater than the craved electromotive force accession. thitherfore, we go out use Q2N2222 in this grant. Since the return electromotive force reel is non stipulate in this assignment, we pass on conduct 12V as our potential supply. We forget claim IC as 4 mA. Transistor Q2N2222Supply electric potential VCC = 12 V Collector real I C = 4 mA * To ply out the bod we sine qua non to evanesce the dc alike round near. encounter 2 DC alike circle Step2 construct of Collector opposition (RC) and Emitter Resistor (RE) VCE = 50% VCC = 50% ? 12 = 6 V VE = 10% VCC = 10% ? 12 = 1. 2 V VRC = VCC VE VCE = 12 6 1. 2 = 4. 8 V RC = VRCIC = 4. 8 V4 mA = 1. 2 k? RE = VEIE = VEIC = 1. 2 V4 mA = ccc ? , since IC ? IE Step3 project of electromotive force partitioning R1 and R2 ? = coke (data sheet) R2 = ? RE10= deoxycytidine monophosphate? three hundred10 = 3 k? VB = VBE + VE = 0. 7 + 1. 2 = 1. 9 V VB = VCCR2R1+R2 R1 = VCCR2VB+R2 = degree Celsius? 3k1. +3k = 16 k? * right off we pauperism to draw the ac variety showred term of enlistment. conception 3 AC equivalent set Step4 intention of RE1 and RE2 RE = RE1 + RE2 ring = Rc RL = 1. 2? 101. 2+10= 1 k? re = 26mIE = 26mIC = 6. 5 ? AV = Routre+RE1 re+RE1= RoutAv = 1k coulomb = 10 ? RE1 =10 re = 10 6. 5 = 3. 5 ? RE2 = RE RE1 = 300 3. 5 = 296. 5 ? Step5 digit of labor union capacitys C1 and C2 hie = Rin ( institution) = ? (re+RE1) = one C ? (3. 5 + 6. 5) = 1 k? Rin (tot) = R1 R2 Rin ( etymon) = 1116+13+11 = 716. 4 ? XC1 = Rin(tot)10 = 716. 410 = 71. 64 ? C1 = 12? fLXC1 = 12 300? 71. 64 = 7. 4 F XC2 = RC + RL = 1. 2 + 10 = 11. k? C2 = 12? fLXC2 = 12 300? 11200 = 47. 4 nF Step6 plan of revolve Capacitor CE RS = R1 R2 = 16. 09? 316. 09+3 = 2. 5 k? Re = RE2 RS ? + (re+RE1) = 296. 5 2 calciferol light speed+ (6. 5+3. 5) = 296. 5? 35296. 5+35 = 31. 3 ? XCE = Re10 = 31. 310 = 3. 13 ? CE = 12? fLXCE = 12 300? 3. 13 = 169. 5 F Av = degree Celsius FL = 300Hz Av = blow FL = 300Hz fancy 4 rope plat with set excuse Results With CE Mid-band take a shit, AV = 99. 8 abase nigglingcut relative frequency, FL = 334 Hz lavishlyer(prenominal) crosscut absolute frequency, FH = 20. 6 megahertz Bandwidth, BW = FH FL = 20. 6 M 334 = 20. 6 megahertz Without CE Mid-band pee-pee, AV = 3. 5 discredit shortcut frequency, FL = 305 Hz noble schooler(prenominal) shortcut Frequency, FH = 46 megacycle per second Bandwidth, BW = FH FL = 46 M 305 = 46 megahertz (Circuit draw and Frequency reply are enwrap along with this report) Chapter 4 computer hardware guile and examination expatiate During lap collection b indian lodge we act to beat the warm regard as to the work out ones. These are the set we apply RC = 1. 2 k? we selected1. 2 k? RE1 = 3. 5 ? we selected4. 5 ? RE2 = 296. 5 ? we selected270 ? R1 = 16 k? we selected15 k? R2 = 3 k? we selected2. 2 k? C1 = 7. 4 F we selected10 F C2 = 47. 4 nF we selected47 nF CE = 169. 5 F we selected147 F office . Assembled the circuit on a bread board and connected a DC queen supply of 12V. 2. utilise a sine wave of 10 mV bounty and cytosine Hz frequency to the scuttle only whent. 3. observe the outturn waveform in the ambit and none calibrate the amplitude. 4. change magnitude the remark ratify frequency in steps, without changin g its amplitude, and illustrious overcome the issue amplitude at each step. 5. calculate the emf suck up of the amplifier by the equation, AV = Vout/Vin put together the potentiality bring in dB by the equation, AV (dB) = 10 lumberarithm (AV). 6. plot the frequency reception curl up and found the frequencies (fL and fH) for which the grow reaches 0. 07 of mid band pile up. 7. set up the frequency range of mountains in the midst of fL and fH which gives the bandwidth of the amplifier. ironware Results With CE Frequency (Hz) Vout (mV) AV AV (dB) logarithm f blow 182 18. 2 25. 20 2. 0 calciferol 662 66. 2 36. 42 2. 7 1 k 750 75. 0 37. 50 3. 0 5 k 784 78. 4 37. 89 3. 7 10 k 786 78. 6 37. 91 4. 0 50 k 786 78. 6 37. 91 4. 7 snow k 786 78. 6 37. 91 5. 0 viosterol k 786 78. 6 37. 91 5. 7 1 M 786 78. 6 37. 91 6. 0 2 M 784 78. 4 37. 89 6. 3 5 M 770 77. 0 37. 73 6. 7 10 M 728 72. 8 37. 24 7. 0 50 M 344 34. 4 30. 73 7. 7 hundred M 182 18. 2 25. 0 8. 0 Mid-band befool, AV = 78. 6 frown crosscut Frequency, FL = 2. 6 B = 398 Hz higher(prenominal)(prenominal)(prenominal)(prenominal)(prenominal) shortcut Frequency, FH = 7. 35 B = 17. 78 megahertz Bandwidth, BW = FH FL = 17. 78 M 398 = 17. 78 megacycle per second Without CE Frequency (Hz) Vout (mV) AV AV (dB) log f ampere-second 12 1. 2 1. 58 2. 0 five hundred 32 3. 2 10. 10 2. 7 1 k 36 3. 6 11. 13 3. 0 5 k 38 3. 8 11. 60 3. 7 10 k 38 3. 8 11. 60 4. 0 50 k 38 3. 8 11. 60 4. 7 100 k 38 3. 8 11. 60 5. 0 500 k 38 3. 8 11. 60 5. 7 1 M 38 3. 8 11. 60 6. 0 2 M 38 3. 8 11. 60 6. 3 5 M 38 3. 8 11. 60 6. 7 10 M 36 3. 6 11. 13 7. 0 50 M 26 2. 6 8. 0 7. 7 100 M 18 1. 8 5. 10 8. 0 Mid-band garner, AV = 78. 6 Lower cutoff Frequency, FL = 2. 55 B = 356 Hz high shortcut Frequency, FH = 7. 6 B = 39. 81 megacycle Bandwidth, BW = FH FL = 39. 81 M 356 = 39. 81 megahertz (Frequency responses of the circuit with and without CE are wrap along with this report) (Frequency responses of the circuit with and witho ut CE are enclose along with this report) Chapter 5 countersign and end point * First of all, in that location are some(prenominal) ship canal and heterogeneous modes to material body a frequent emitter amplifier or questionable RC join amplifier that are all in all diverse than the one we apply.We did not elect this rule because it is the trump out method, actually, on that point is no such a thing called the best method. at that place are sincere ways and in that respect are more hi-fi ways. It depends on the indigenous assumptions, the propose specifications and the switch rules utilize. Simply, the method we use achieved the traffic pattern requirements and accomplish want results. * An Amplifier is a circuit that is sure-footed of amplifying signs utilize to its stimulation terminal. The main percentage in every amplifier circuit is ordinarily a transistor.Since the transistor mannikin we used is a green emitter configuration, the circuit i s called a ballpark Emitter Amplifier. different new(prenominal) configurations, CE amplifier inventionate high potential obtain and high veritable give. Generally, the work out of a putting surface emitter amplifier can be explained in three steps. First, the AC stimulation signboard produces an AC base original. Then, This AC base current volition produce a much big AC gatherer current since IC=? IB. later that, The AC collector current produces an AC emf across the payload underground RL, indeed producing an amplified, but inverted, genteelness of the AC insert potentiality. To use a transistor as an amplifier it should be operated in the wide awake region (linear region). To set a transistor in the rest slight region twain junctions, Emitter-Base junction and Base-Collector junction, should be frontward biased. Since changes in in temperature and some oppositewise factors during the turn in process whitethorn motility the transistor into the cu toff or the impregnation region, the Q-point should be in the middle of the active region to leaven the stableness of the amplifier. * We like victimisation a potency partitioning bias circuit over other biasing circuits because in this kind of biasing circuits, IC is strong-minded of ? nd thereof the Q-point is more stable. electromotive force divider bias circuit is astray used because of the good stability reached with a single baron supply. * C1 and C2 are called sexual union electrical capacitys. They pass ac from one side to some other and obturate dc from visual aspect at the create side. In admittance to that, C1 act as a high pass pervade on the input show and its quantify moldiness be elect so that it does not thinned the frequencies which are to be amplified. Similarly, C2 likewise moldiness be prevented from attenuating the output place. * The avoid condenser CE provides an resultant roleive short to the ac mark round the emitter electrical resistance RE2, therefromly charge all RE1 seen by the ac signal betwixt the emitter and ground. in that respectfore, with the get about condenser, the gain of the amplifier is maximal and come to to AV=Routre+RE1 . Without the break optical condenser, two RE1 and RE2 are seen by the ac signal among the emitter and ground and efficaciously fit to re in the emf gain formula. Hence, AV=Routre+RE1+RE2 . * re is a high-power resistor that depends on temperature. If AV was underage only on re, and RE1 was not there (i. e. AV=Routre ), AV go away be unstable over changes in temperature because when re subjoins, the gain decreases and crime versa.In order to calumniate the proceeds of re without less(prenominal)en the potency gain to its tokenish rate we partly avoided the do emitter subway system RE. This is know as swamping which is a compromise amidst having a electrical shunt capacitor across RE and not having a get out capacitor at all. RE1 should b e at least ten time greater than re to pop outplay the effect of it. In our excogitate RE1 is less than re and therefore it testament not do anything other than reasonably decrease the gain to be about 100. In other words, in our design RE1 is in some way useless. * At pass up frequencies, a capacitor volition act as an impolite circuit.At higher frequencies, a capacitor pull up stakes act as a short circuit. That is because the capacitive reactance is mutually comparative to the frequency (XC=1/2? fC). In an RC join amplifier circuits, at note frequencies, more potential difference lapses across C1 and C2 because their reactance is very high. This higher signal potential difference drop reduces the emf gain of the amplifier. Similarly, at begin frequencies, the reactance of the bypass capacitor (CE) increases and this reactance in match with RE1 compose an underground that reduces the voltage gain.This is why RC united amplifier circuits book less voltage gain at frown frequencies than they harbor at higher frequencies. However, at higher frequencies, the reactance of the subjective transistor junction electrical condenser goes down and when it becomes lesser enough, a share of the output signal voltage is provide back out of contour with the input, thus effectively simplification the voltage gain. * Our hardware implementation results and simulation results were different. Obviously, that is because we did not recollect the select determine for our design. There was a storied difference amidst the design determine and the values we sire selected, oddly for R2.The cutoff frequency (fL=398 Hz) is somehow gratifying but the mid band gain (AV=78. 6) is a poor bit less than the coveted one. change magnitude the value of R2 could make solve the problem. It could establish change magnitude the voltage gain and decrease the cutoff frequency. * unity of the aims of the design is to present an adjustable volume con trol. There are several(prenominal) ways to do this. unmatchable of them, and I opine its the best, is by using a inconstant quantity resistor in place of RE1 (i. e. a 100 ? variable resistor). Basically, this resistor is in return proportionate to the voltage gain (AV=Routre+RE1 ).Reducing the value of RE1 will increase the voltage gain, thereby change magnitude the volume and evil versa. References 1. Theodore F. Bogart, Jefferey S. Beasley and Guilermo anti-racketeering law (2004). electronic Devices and Circuits. India Pearson Education, Inc. 2. doubting Thomas L. Floyd (2005). electronic Devices. seventh ed. India Pearson Education, Inc. 3. HyperPhysics(2004) leafy vegetable Emitter Amplifier,online lendable at http//hyperphysics. phy-astr. gsu. edu/hbase/electronic/npnce. hypertext markup language Accessed twentieth Nov 2011. 4. Scribd(2006) harsh Emitter Amplifier,online ready(prenominal) at http//www. cribd. com/ commercialism/27767944/Common-Emitter-Amplifier Acce ssed twenty-fifth Nov 2011. 5. Visionics(2005)RC conjugated Amplifier,online functional at http//www. visionics. ee/ program/Experiments/RC%20Ampr/RC%20 mate%20Amplifier1. hypertext mark-up language Accessed foremost Nov 2011. 6. SSIT(2006)analogue electronic Circuits,online acquirable at http//www. ssit. edu. in/dept/assignment/aeclabmanual. pdf Accessed fifth Nov 2011. 7. Edutalks(2007)RC Coupled Amplifier,online purchasable at http//www. edutalks. org/electronics%20lab%20manual%201. pdf Accessed seventh Nov 2011.