Report_Điện_Tử_2.docx

Trng i hc FPTkhoa in t & Truyn thng

Bn Bo Co Thc Hnh

Ti:MCH PHT M THANH N GIN VI MIC

Nhm 3: Sinh Vin Thc Hin:H Cng Anh- SE90139.Phm Vn Anh- SE02918.Phan Thnh Hng- SE02617Hunh Hc- SE02873 c Hi- SE02714

Ging vin hng dn : Trng Vnh Ln.

Mc Lc

PHN 1: GII THIU TNG V XY DNG CH TIU K THUT CA SNPHM...................................................................................................................3.1.1 Phn tch nhu cu v s cn thit ca sn phm cho ng dng thc hin t......................................................................................................3.1.2 Chc nng sn phm.............................................................................3.1.3 Cc ch tiu k thut mch in...........................................................3.

PHN 2: LP K HOCH........................................................................................3.

PHN 3: LA CHN PHNG N K THUT...................................................4.3.1S khi Ca Sn Phm.....................................................................4.3.2 S nguyn l ca mch.....................................................................5.3.3Chc Nng C Th Linh Kin Theo L Thuyt..................................6.3.2.1 in tr........................................................................................6.3.2.2Bin tr.........................................................................................8.3.2.3T in..........................8.3.2.4Microphone.................................................................................10.3.2.5IC LM386.....................................................................................11.3.2.6Loa................................................................................................12.3.4 M hnh proteus13.

PHN 4: TRIN KHAI..............................................................................................14.

PHN 5: THC NGHIM. ......................................................................................15.

PHN 6: CC LINH KIN CN S DNG..........................................................17.

PHN 7: CC NGUN THAM KHO..................................................................18.

PHN 1: GII THIU TNG V XY DNG CH TIU K THUT CA SN PHM.1.1 Phn tch nhu cu v s cn thit ca sn phm cho ng dng thc t. phc v nhu cu lm vic v gii tr ca con ngi khi ta mun khuych i m thanh khi ni hay mun iu chnh m lng ph hp m ta mun nghe.1.2.Chc nng sn phm.Sn phm s dng ngun in 1 chiu 5V cung cp cho mch in, khi c m thanh t Mic ( tn hiu m thanh t jack 3.5 ) vo th mch s khuych i m thanh v s pht ra loa.1.3.Ch tiu k thut mch in- Hot ng n nh trong di in p 4V-12V hoc 5V-18V.- Pht ra m thanh loa khi c m thanh t MIC vo .( jack 3.5)- Ti thiu ha cc mch h tr bn ngoi.+ Tn hiu u vo.Tn hiu u vo l tn hiu m thanh, c th l ting ni, ting ng, nhc...( hay tn hiu t laptop )+Tn hiu u ra.Tn hiu u ra l m thanh ln hn u vo, c th l loa pht ra.

PHN 2: LP K HOCH.K hoch thc hin v phn cng nhim v cho tng thnh vin tham gia:

McCng vicNgi thc hinBt u Kt thc

1Xy dng tngC nhm02/1103/11

2Mua linh kin Cng Anh-Hi- Hc04/1104/11

3Lp mchCng Anh- Hi- Vn Anh05/1107/11

4M phng mchHng05/1106/11

5Vit bo co- Thuyt trnhHc-Hi08/1110/11

Bng 2.1: bng phn cng nhim v.

PHN 3: LA CHN PHNG N K THUT

3.1S khi ca sn phm.

Tn hiu inTn hiu in

Khi hin thKhi khuych iDng inKhi cm binKhi ngun

Tc ng

Tc nhn

Hnh 3.1.1: S Khi.

Tc nhn: m thanh( ting ng, ging ni, nhac). Khi cm bin (MIC): C chc nng chuyn i m thanh sang tn hiu in . Khi ngun: C nhim v cung cp ngun in cho mch, y l ngun 1 chiu 5V. Khi khuych i( IC LM386): khuych i tn hiu in t. Khi hin th (Loa): Bin tn hiu in t thnh c hc v sau pht ra m thanh.

3.2.S nguyn l ca mch ( m phng bng phn mm proteus ):

Hnh 3.2.1: S m phng theo Protel Dxp.( Cc bn c th c hng dn dng theo link http://doan.edu.vn/do-an/do-an-ung-dung-cong-nghe-thong-tin-cho-dien-tu-vien-thong-21586/ hoc xem mch bng AltiumDesignerViewer )

+Nguyn l hot ng ca mch:

Khi c m thanh( ting ng, ging ni, nhc) pht vo Mic th Mic s chuyn i nng lng m hc sang cm bin in t (tc chuyn i m thanh sang tn hiu in t). Sau , transistor BJT trong IC LM386 s khuych i tn hiu. Khi dng in t n loa th loa s bin nng lng in t sang nng lng c hc v pht ra m thanh.+ C th trong mch: MIC: tc chuyn i m thanh sang tn hiu in t. IC LM386: khuych i cng sut c thit k p dng cho in p thp. Loa: chuyn lng in t sang nng lng c hc v pht ra m thanh. in tr R2 cp ngun cho MIC v mch, R5 n nh ngun, C4 v C7 l cu ni truyn tn hiu, cho in p xoay chiu i qua; (C2 nt R1) v (C8 nt R4)tc dng p ng tn s hot ng BJT; bin tr R3 iu chnh iu chnh tn hiu in vo ic;C3 lc b thnh phn AC gim ting ca loa;C5 dn tn hiu t ngun vo;(C9 nt R6) hp thnh mch lc RC n nh ngun; C6 cng vi ti u ra loa c tnh cm thnh b loc LC. Chn 1 v chn 8 ni vi nhau trong IC LM386 bng t C1 tng tch in p ( v ty vo mch m ta tng tch cho ph hp mc thm t v tr tch in p t 20-200 ) Header 2x2: ni dy.

3.3: Chc nng c th theo l thuyt.3.3.1. in tr.3.3.1.1 Khi nimin tr l mt linh kin th ng khng th thiu trong cc mch in v in t, chng c tc dng cn tr dng in, to s st p thc hin chc nng ty theo v tr ca in tr trong mch. Ta c th hiu mt cch n gin in tr l mt s cn tr dng in ca mt vt dn in, nu mt vt dn in tt th in tr nh, dn in km th in tr ln v cch in th in tr bng v cng.K hiu: RBiu thc xc nh: R=U/In v tnh: (Ohm)3.3.1.2 Phn loiCc in tr c chia ra lm hai loi chnh in tr c nh v in tr bin iC 3 loi in tr thng c ch to v s dng:+ in tr mng than( Ccbon-Film)+in tr mng kim loi(Metal-Film)+in tr dy qun.3.3.1.3 c im ca din trc tnh cn thit ca in tr l kh nng chu ti v h s nhit .in tr lm vic ph thuc vo nhit ca n, do tr s thay i khi c dng chy qua s c hin tng bin i nng lng in thnh nng lng nhit trn than in tr.Gi tr in tr cn thay i theo thi gian hay trong nhng iu kin c bit theo tn s tn hiu xoay chiu tc ng ln n.Gi tr gii hn: Cng sut cc i cho php(Pmax)in p lm vic cc i cho php(Umax)Nhit cc i cho phpKhi c hai hay nhiu in tr R1, R2,, Rn mc ni tip nhau th gi tr in tr tng cng bng tng cc in tr ring r: R=R1+R2+.+Rn (khi I=I1=I2=.=InV U=U1+U2+.+Un)Khi mc hai hay nhiu in tr R1,R2,.,Rn song song th ienj tr tng ng ca chng c tnh bi

U=U1+U2+...+UnI=I1+I2+...+In3.3.1.4 Cu to c bn v quy c gi trCu to c bn ca in tr:-in tr mng than:Than c p thnh mt lp rt mng bn ngoi than gm hnh tr hoc bn phng.-in tr mng kim loi: Mt lp v mng kim loi c bay hi v kt t trn than gm nh vt liu c in tr.-in tr dy qun: Dy kim loi hoc hp kim c un quanh mt ng s v ni vo m bt u ng s, chn ni cng c hn vo m bt u ny.Quy c gi tr in tr

Hnh 3.3.1.1: Bng quy c mu sc in tr.

K hiu: Hnh nh:

3.3.2.Bin tr.- Bin tr l in tr c th thay i c tri s.- Bin tr c th c s dng iu chnh cng dng in trong mch khi thay i tr s in tr.-in tr ca thit b c th c thay i bng cch thay i chiu di dy dn trong ca cc thit b hoc bng cch tc ng khac nh nhit thay i, nh sng hay bc x in t.

Hnh 3.3.2.1: K hiu ca bin tr trong mch in

3.3.3T in.3.3.3.1 Khi nim

T in l mt linh kin th ng dng lm phn t tch tr v gii phng nng lng trong mch in. Thng thng i vi dng in mt chiu th t in c tr khng rt ln cn vi dng xoay chiu th tr khng t in thay i ty theo tn s dng in.K hiu l C.n v tnh Fara(F).3.3.3.2 Phn loi t inC rt nhiu phng php phn loi, nu phn loi theo tnh cht th c 2 loi:+ T khng phn cc: Gm cc l kim loigheeps xen k vi lp cch in mng.+T phn cc: C cu to gm 2 in cc cch ly nhau nh mt lp cht in phn mng lm in mi.Nu phn loi theo cu to th c 7 loi chnh:+T gm: in mi bn gm c kch thc nh.+T mica: in mi bn mica trng bc.+T Pholycacbonat: C dng tm ch nht, kch thc nh gn, in dung ln.+T giy polyste: Cht in mi lm bng giy p tm polyste c dng hnh tr.+T ha: C cu to l l nhm cng bt dung dch in phn cun li t trong v nhm, in p lm vic thp, kch thc v sai s ln.+T tan tan: Dng hnh tr c u radocj theo trc v dng hnh vin tan tan.+T bin i: Chnh l t xoay trong radio hoc t tinh chnh.

3.3.3.3 c im t in

+Dng tch in, v x in, ch cho tn hiu xoay chiu i qua, ngn dng mt chiu.+Kh nng np hay x in nhiu hay t ph thuc v in dung C ca t.+n v o in dung ca t mch: pF, nF, uF.+Khi s dng t phai quan tm n 2 thng s: in dung cho bit khae nng cha in ca t v in p cho bit kh nng chu ng ca t.+Ghp ni tip: Cc t C1,C2, ., Cn ghp ni tip th in dung tng ng C ca b t c gi tr xc nh bi 1/C=1/C1+1/C2+.+1/Cn +Ghp t song song: Cc t C1, C2,.,Cn ghp song song th in dung tng ng C ca b t c xc nh bi: C=C1+C2++Cn+Ghp t a ni tip thi dng t ny ni m t kia, song song th ni cng cc.3.3.3.4 Cu to v k hiu quy c gi tr-T khng phn cc: Gn cc l kim loi xen k vi cc l lm bng cht cch in gi l cht in mi. Tn ca t c t theo tn cht in mi nh t gm, t mica gi tr ca t c in dung t 1.8pF-1mF.-T in phn: T in phn c cc to gm 2 in cc tch ri nhau nh mt mng mng cht in phn, khi c mt in p tc ng ln hai in cc s xut hin mt mng it kim loi khng dn in ng vai tr nh lp in mi. Lp in mi cng mng kch thc ca t cng nh m in dung li ln.Quy tc xc nh gi tr:-Cc loi t c dng m+M s thng c dung cho cc laoij t c gi tr nh trong cc gi tr c nh ngha ln lt nh sau: Gi tr th nht l s hang hc, th 2 l hang n v, th 3 l s s khng ni tip theo gi tr ca s totuwf gi tr 1 v gi tr 2. Gi tr ca t c c theo chun l gi tr picro Fara(pF). Ch s i km sau cng ch gi tr sai s ca t, V d t ghi 102 tc 1000pF-T dng m mu-S dng ch yu trn cc t loi polyester trong rt nhiu nm. Hin nay cc loi t ny khng cn bn trn th trng na nhng chng vn tn ti trong kh nhiu cc mch in t c. Mu c nh ngha cng tng t nh i vi mu trn in tr. Ba mu trn cng ln lt ch gi tr t tnh theo pF, mu th 4 l ch dung sai v mu th 5 ch ra gi tr in p.

3.3.4Microphone

Microphone (hay cn gi l mic) l mt b chuyn i m thanh thnh tn hiu in t. Micro c s dng trong nhiu ng dng nh in thoi, my ghi m, h thng karaoke, my tr thnh, sn xut phim, loa, i pht thanh v truyn hnh v trong cc my tnh ghi m ging ni, nhn dng ging ni, VoIP.Cu to ca Microphone-Mng rung (diaphragm): m tanh p vo mng rung to ra cc rung ng theo sng m. c th ti to li c cc m thanh c tn s cao th mng rung phi cng mng cng tt.-Bin nng (transducer):Bin i nhng rung ng c hc ca mng rung thnh cc tn hiu in.-V chp (casing):Ngoi vic bo v cho mng rung v bin nng, v chp cn gip iu khin hng thu ca microphone.Phn loi MicrophoneC ba kiu microphone thng dng: dynamic, ribbon v condenser microphone.-Dynamic microphones bng nguyn l cm ng in t, ngi dng thng gi dng micro ny l mic karaoke, v hu ht cc bn s thy n trong cc h thng ht karaoke hoc sn khu. Nhng trong thu m vn c mt s loi mic dynamic c thit k thu thanh.-Condenser Microphone vn hnh theo nguyn l chuyn ng ca mng rung. trng thi bnh thng condenser microphone c mt mt b phn thu a hng. Mt s l nh c c trn "a hu" gip lm iu ny. Cc l nh c tc dng lm chm cc m thanh ng sau mng rung, ch cc m thanh ng trc, ri sau lc b m thanh u ra. Tn s c lc ph thuc vo kch c v v tr ca cc l.Loi micro ny c nhy rt cao v bt m thanh chnh xc, thch hp cho thu cc dng tn hiu mm nh ging ht, guitar thng...nn dng micro ny c cc phng thu m s dng. Condenser microphone thng hi b rung ting khong tn s t 8 n 12 kHz.-Ribbon microphone hot ng cng nh dynamic microphone. im khc bit chnh l b bin nng ca n l mt di l aluminum cc mng, rng v nh c th rung c khi cc phn t khng kh ca sng m di chuyn. Tuy nhin do tn hiu in t sinh ra rt nh so vi dynamic microphone nn phi cn n mt b chuyn dng nng tn hiu u ra.

Hnh 3.3.4 Hnh nh cu to ca Dynamic microphones

3.3.5 IC LM386 IC LM 386 IC l b khuych i cng sut c thit k p dng cho in p thp. Thng s k thut nh sau:

Hnh 3.3.5.1 Thng s k thut ca IC LM386 a)Cu to bn trong:

Hnh 3.3..5.2 Cu to bn trong ca IC LM386

b) S chn :

Hnh 3.3.5.3 S chn ca IC LM386

3.3.6 Loa

Hnh 3.3.6.1 Dng thc t ca loa bass

Hnh 3.3.6.2 Dng thc t ca loa treble-Nguyn l hot ng ca loa:Loa in hot ng theo nguyn tc mt cun dy t trong mt t trng mnh ca nam chm. Khi c dng in m tn ch qua, cun dy s dao ng. Do cun day c ni vi mng loa nn cc dao ng ny c truyn ra khng kh, tc ng vo tai ngi nghe.D th loi no th loa cng phi c mt b phn quan trng gi l mng rung( hoc mng loa). Mng rung l ni m thanh c pht ra n tai ngi nghe. Ty tng loi loa khc nhau m nguyn l lm rung mng rung l khc nhau.a s cc loa mng rung c gn vi mt cun dy, cun dy ny c nh v trong khe hp c t trng mnh c sinh ra gia ha cc ca mt nam chm vnh cu. Khi cho dng in tn hiu i qua cun dy th cun day xut hin lc t lm rung n, s rung ng ca cun day s lm chuyn dng mng loa.Do hn ch ring v cu to, mi loi loa in hot ng theo nguyn l s dng nam chm in vnh cu thng ch c pht m thanh tt nht mt di tng nht nh no m khng th pht ton di m nghe c(16Hz->20000 Hz). di tn thp, m thanh cn c bin ln tai ngi cm nhn c, mng loa phicos cu to kch thc rng, cc cun dy c bin ng giao ng ln trongkhe t. di tn cao, p ng s giao ng nhanh v lien tc, mng loa phi nh, mm khng cn tr. di tng trung bnh hoc trng di tn nht nh, mng loa cn c tnh ton ph hp nht vi tn s pht thit k.Nh vy c th truyn ti m thanh mi di tn nghe c, mt b loa cn c s dng nhiu loa vi dng knh v cu to khc nhau( thng thng mt thng loa c cht lng tt thng bao gm bn n nm loa, trong : mt loa trm, hai loa trung v mt n hai loa pht tn s cao).Thng s ca loa:+ in tr loa: Thng k hiu bng m v xc nh bng in tr ca loa khi do tn s 1 Khz.+Cng sut danh nh: Cng sut in, tnh bng VA hoc W.+Di tn ti to.+Tr khng loa.+H s sng di+p lc tiu chun trung bnh.3.3.7 Mch lc RCMch RC c in n ti Vi Tn s thp , c in gim t Vin 0 Tn s cao . V vy, mch RC thch hp cho vic to B Lc Tn S ThpB Lc Tn S Thp c cc tnh cht sau:1. in n tn s thp v in Gim tn s cao .2. tn s gc = 1 / RC in th cn mt na.3. To t hai linh kin in t in Tr v T in mc theo li RC4. B Lc Tn S Thp c cng thc ton tng qut

T = RC

5. Cng dng: Chng tp m cao tn, nhiu cao tn xut hin trong mch hoc ca mi trng tc dng vo si dy, va c tc dng lm gim cht it di cao thuc m tn nn gip cho m thanh c tr nn m p ngt bi hn. 6: u im v nhc im:

-u im: + B lc RC l loi b lc n gin nht, gi thnh r. +Vn hnh n nh.-Nhc im: + C tn hao trn in tr , tn hao ny cng l n khi cng sut ln. +Kh nng chn lc tn s km.3.4 S Proteus:

Hnh 3.3.7.1: Mch M Phng Bng Proteus.PHN 4: TRIN KHAI.

Cng vicNgi thc hinYu cu

Tm hiu s nguyn l mchC nhmNm r c nguyn l hot ng ca mch sa cha khi mch khng hot ng.

M phng mch bng ProteusHngM phng chnh xc trc khi bt tay vo lp rp mch, mch c m phng phi chy.

Mua linh kinCng Anh-hi-HcMua v ng linh kin, m bo linh kin chy tt.

Lp rp mchCng Anh-Hi-Vn AnhLp rp mch da trn s nguyn l, mch lp rp phi p v chy c.

Vit bo coHcBo co y , r rng chi tit, trnh gy kh hiu hoc hiu nhm cho ngi c.

Thuyt trnhHiM t c mch v chc nng tng linh kin trong mch.

Bng 4.1: K hoch trin khai.

PHN 5: THC NGHIM.

Sau khi lp c mch, nhm em thc hin demo sn phm v thu c kt qu sau:

Hnh 5.1: Mt trc ca sn phm.

Hnh 5.2: Ton b sn phm.

Hnh 5.3: Cu trc bn trong sn phm.

y l video clip Nhm mnh thuyt trnh qua v sn phm Cc bn c th tham kho link sau y : http://www.youtube.com/watch?v=Y9AeVt9zcmQ&feature=youtu.be

PHN 6:CC LINH KIN CN S DNG.

-T gm 6 ci,- T in: 1 ci 10uF, 1 ci 220uF, 1 ci 50nF- in tr: 2 ci 10k, 2 ci 510k,1 ci 10-Bin tr: 1 ci.- Mic: 1 ci ( or jack 3.5 )-Loa: 1 ci-IC LM386: 1 ci-Header 2x2: 1 ci

Tng c tnh gi c: 100.000 vn. ( Nu cc bn c th tn dng cc linh kin trong cc tivi, radio, micro b hng th s gim chi ph rt nhiu )

PHN 7:CC NGUN THAM KHO.

1. dientuvietnam.net2. vatgia.com3. google.com4. tailieu.vn5.tinhte.vn6.electroschematic.com7.en.wikipedia.org8.brighthubengineering.com9.http://satsleuth.com/schematics.htm

Cui cng, thay mt nhm thc hin, em xin chn thnh cm n thy gp v hng dn chng em hon thnh bi thc hnh ny.

Thay mt nhm thc hin.

H Cng Anh

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