Mch Khuch i Cng Sut m Thanh n
I
PHN I :
L THUYT TNG QUANCHNG 1:CC LINH KIN S DNG 1.1 in tr: s dng in tr 4 vng mu v 5 vng mu. K hiu: 1.2 T in: Cng dng ca t l tch v phng in. Gm c t phn cc v khng phn cc. K hiu: T phn cc T khng phn cc 1.3 Diode: Dng nn in hay chnh lu, n nh in p, hn bin tnh hiu, trnh c nhiu, tch tnh hiu ra khi sng mang cao tn, chn cng hng i. K hiu: 1.4 Transistor: l linh kin bn dn gm ba lp bn dn tip gip nhau to thnh mi ni P N. Gm c 2 loi: N P N v P N P. K hiu:N - P - N P - N - P
1.4.1/ A1013:
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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1.4.2/C2383:
1.4.3/ C1815 :
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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1.4.4/ 2N5551:
4.5/ B688:
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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1.4.5/ B688:
1.4.6/ D718:
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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1.5 IC 4558:
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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CHNG 2: MCH KHUYCH I THNG DNG 2.1. Khi nim v mch khuch i: Mch khuych i c s dng trong hu ht cc thit b in t, nh mch khuych i m tn trong Cassete, Ampli, khuych i tn hiu video trong Ti vi mu v.v ...
Hnh: 2.1 C ba loi mch khuych i chnh l : Khuych i v in p : L mch khi ta a mt tn hiu c bin nh vo, u ra ta s thu c mt tn hiu c bin ln hn nhiu ln. Mch khuych i v dng in : L mch khi ta a mt tn hiu c cng yu vo, u ra ta s thu c mt tn hiu cho cng dng in mnh hn nhiu ln. Mch khuych i cng xut : L mch khi ta a mt tn hiu c cng xut yu vo, u ra ta thu c tn hiu c cng xut mnh hn nhiu ln, thc ra mch khuych i cng xut l kt hp c hai mch khuych i in p v khuych i dng in lm mt. 2.2. Ba cch mc Transistor c bn: 2.2.1 Transistor mc theo kiu E chung: Mch mc theo kiu E chung c cc E u trc tip xung mass hoc u qua t xung mass thot thnh phn xoay chiu, tn hiu a vo cc B v ly ra trn cc C, mch c s nh sau :
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Rg : l in tr ghnh Rt : L in tr nh thin Rpa : L in tr phn p
Hnh: 2.2 Mch khuych i in p mc kiu E chung, tn hiu a vo cc B v ly ra trn cc C. c im ca mch khuych i E chung.
Mch khuych i E chung thng c nh thin sao cho in pUCE khong 60% 70 % Vcc. Bin tn hiu ra thu c ln hn bin tn hiu vo nhiu ln, nh vy mch khuych i v in p. Dng in tn hiu ra ln hn dng tn hiu vo nhng khng ng k Tn hiu u ra ngc pha vi tn hiu u vo : v khi in p tn hiu vo tng => dng IBE tng => dng ICE tng => st p trn Rg tng => kt qu l in p chn C gim , v ngc li khi in p u vo gim th in p chn C li tng => v vy in p u ra ngc pha vi tn hiu u vo. Mch mc theo kiu E chung nh trn c ng dng nhiu nht trong thit b in t.
2.2.2 Transistor mc theo kiu C chung :
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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Hnh: 2.3
Mch mc theo kiu C chung c chn C u vo mass
hoc dng ngun Lu : v phng din xoay chiu th dng ngun tng ng vi mass, tn hiu c a vo cc B v ly ra trn cc E. ra trn cc E c im ca mch khuych i C chung . Tn hiu a vo cc B v ly ra trn cc E Bin tn hiu ra bng bin tn hiu vo : V mi BE lun lun c gi tr khong 0,6V do khi in p chn B tng bao nhiu th p chn C cng tng by nhiu => v vy bin tn hiu ra bng bin tn hiu vo . cng gim. Cng ca tn hiu ra mnh hn cng ca tn hiu vo nhiu ln : V khi tn hiu vo c bin tng => dng IBE s tng => dng ICE cng tng gp ln dng IBE v ICE = .IBE gi s Transistor c h s khuych i = 50 ln th khi dng IBE tng 1mA => dng ICE s tng 50mA, dng ICE chnh l dng ca tn hiu u ra, nh vy tn hiu u ra c cng dng in mnh hn nhiu ln so vi tn hiu vo. Mch trn c ng dng nhiu trong cc mch khuych i m (Damper), trc khi chia tn hiu lm nhiu nhnh , ngi ta thng dng mch Damper khuych i cho tn hiu kho hn . Tn hiu ra cng pha vi tn hiu vo : V khi in p vo tng => th in p ra cng tng, in p vo gim th in p ra Mch mc kiu C chung , tn hiu a vo cc B v ly
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n
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Ngoi ra mch cn c ng dng rt nhiu trong cc mch n p ngun ( ta s tm hiu trong phn sau ) 2.2.3 Transistor mc theo kiu B chung : Mch mc theo kiu B chung c tn hiu a vo chn E v ly ra trn chn C , chn B c thot mass thng qua t. Mach mc kiu B chung rt t khi c s dng trong thc t. Mch khuych i kiu B chung , khuych i v in p v khng khuych i v dng in.
Hnh: 2.4
2.3. Cc ch hot ng ca mch khuch i: Cc ch hot ng ca mch khuych i l ph thuc vo ch phn cc cho Transistor, tu theo mc ch s dng m mch khuych i c phn cc K ch A, ch B , ch AB hoc ch C. 2.3.1 Mch khuych i ch A: L cc mch khuych i cn ly ra tn hiu hon ton ging vi tn hiu ng vo.
Hnh: 2.5Trang 9
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
Mch Khuch i Cng Sut m Thanh n
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Mch khuych i ch A khuych i c hai bn chu k tn hiu ng vo
Transistor hot ng ch A, ta phi nh thin sao cho in p UCE ~ 60% 70% Vcc. * Mch khuych i ch A c s dng trong cc mch trung gian nh khuych i cao tn, khuych i trung tn, tin khuych i v v.. 2.3.2 Mch khuych i ch B: Mch khuych i ch B l mch ch khuych i mt na chu k ca tn hiu, nu khuych i bn k dng ta dng transistor NPN, nu khuych i bn k m ta dng transistor PNP, mch khuych i ch B khng c nh thin.
Hnh: 2.6 Hnh: 2.6
Mch khuych i ch B ch khuych i mt bn chu k ca tn hiu ng vo. * Mch khuych i ch B thng c s dng trong cc mch khuch i cng xut y ko nh cng xut m tn, cng xut mnh ca Ti vi, trong cc mch cng xut y ko , ngi ta dng hai n NPN v PNP mc ni tip , mi n s khuych i mt bn chu k ca tn hiu, hai n trong mch khuych i y ko phi c cc thng s k thut nh nhau. * Mch khuych i cng xut kt hp c hai ch A v B .
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Hnh: 2.7
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
Mch khuych i cng xut Ampli c : Q1 khuych i ch A, Q2 v Q3 khuych i ch B, Q2 khuych i cho bn chu k dng, Q3 khuych i cho bn chu k m. 2.3.3 Mch khuych i ch AB:
Hnh: 2.8 Mch khuych i ch AB l mch tng t khuych i ch B , nhng c nh thin sao cho in p UBE sp s 0,6 V, mch cng ch khuych i mt na chu k tn hiu v khc phc hin tng mo giao im ca mch khuych i ch B, mch ny cng c s dng trong cc mch cng xut y ko . 2.3.4 Mch khuych i ch C: L mch khuych i c in p UBE c phn c ngc vi mc ch ch ly tn hiu u ra l mt phn nh ca tn hiu u vo, mch ny thng s dng trong cc mch tch tn hiu : Th d mch tch xung ng b trong ti vi mu.
Hnh: 2.9
ng dng mch khuych i ch C trong mch tch xung ng b Ti vi mu.SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
2.4. Cc kiu ghp tng: Khi nim v ghp tng : Mt thit b in t gm c nhiu khi kt hp li, mi khi li c nhiu tng khuych i c mc ni tip vi nhau v khi mc ni tip thng s dng mt trong cc kiu ghp sau : Ghp tng qua t in. Ghp tng qua bin p . Ghp tng trc tip. Ta hy xt cc trng hp c th : 2.4.1 Ghp tng qua t in: * S mch ghp tng qua t in:
Hnh: 2.10 Mch khuych i u t - c hai tng khuych i c ghp vi nhau qua t in. trn l s mch khuych i u t trong i Cassette, mch gm hai tng khuych i mc theo kiu E chung, cc tng c ghp tn hiu thng qua t in, ngi ta s dng cc t C1 , C3 , C5 lm t ni tng cho tn hiu xoay chiu i qua v ngn p mt chiu li, cc t C2 v C4 c tc dng thot thnh phn xoay chiu t chn E xung mass, C6 l t lc ngun. u im ca mch l n gin, d lp do mch c s dng rt nhiu trong thit b in t, nhc im l khng khai thc c ht kh nng khuych i ca Transistor do h s khuych i khng ln. trn l mch khuych i m tn, do cc t ni tng thng dng t ho c tr s t 1F 10F.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
Trong cc mch khuych i cao tn th t ni tng c tr s nh khong vi nan Fara. 2.4.2 Ghp tng qua bin p:
Hnh: 2.11 * S mch trung tn ting trong Radio s dng bin p ghp tng:
Hnh: 2.12 Tng Trung tn ting ca Radio s dng bin p ghp tng. trn l s mch trung tn Radio s dng cc bin p ghp tng, tn hiu u ra ca tng ny c ghp qua bin p i vo tng pha sau. u im ca mch l phi hp c tr khng gia cc tng do khai thc c ti u h s khuych i , hn na cun s cp bin p c th u song song vi t cng hng khi mch khuych i mt tn s c nh. Nhc im : nu mch hot ng di tn s rng th gy mo tn s, mch ch to phc tp v chim nhiu din tch.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
2.4.3 Ghp tng trc tip: * Kiu ghp tng trc tip thng c dng trong cc mch khuych i cng xut m tn. Mch khuych i cng xut m tn c n o pha Q1 c ghp trc tip vi hai n cng xut Q2 v Q3.
Hnh: 2.13
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
CHNG 3: MCH KHUCH I THUT TON 3.1. Mch khuch i vi sai:
Hnh: 3.1
Mch in ny dng tm ra hiu s, hoc sai s gia 2 in p m mi in p c th c nhn vi mt vi hng s no . Cc hng s ny xc nh nh cc in tr.
Tng tr vi sai Zin (gia 2 chn u vo) = R1 + R2 H s khuch i vi sai:Nu R1 = R2 v Rf = Rg,Vout = A(V2 V1) v A = Rf / R1
3.2. Mch khuch i o:
Hnh: 3.2
Dng i du v khuych i mt in p (nhn vi mt s m)
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
Zin = Rin (v V l mt im t o) Mt in tr th ba, c tr s nhng n s gim thiu sai s do dng nh thin u vo. , c thm
vo gia u vo khng o v t mc d i khi khng cn thit lm,
3.3. Mch khuch i khng o:
Hnh: 3.3 Dng khuych i mt in p (nhn vi mt hng s ln hn 1)
(thc ra, tng tr bn thn ca u vo op-amp c gi tr t 1 M n 10 T. Trong nhiu trng hp tng tr u vo c th c xem nh cao hn, do nh hng ca mch hi tip.)
Mt in tr th ba, c gi tr bng
, c thm vo gia ngun tn
hiu vo Vin v u vo khng o trong khi thc ra khng cn thit, nhng n s lm gim thiu nhng sai s do dng in nh thin u vo. 3.4. Mch theo in p:
Hnh: 3.4SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
c s dng nh mt b khuch i m, gii hn nhng nh hng ca ti hay phi hp tng tr (ni gia mt linh kin c tng tr ngun ln vi mt linh kin khc c tng tr vo thp). Do c hi tip m su, mch ny c khuynh hng khng n nh khi ti c tnh dung cao. iu ny c th ngn nga bng cch ni vi ti qua 1 in tr.
(thc ra, tng tr bn thn ca u vo op-amp c gi tr t 1 M n 10 T.) 3.5. Mch khuch i tng:
Hnh: 3.5 Mch c s dng lm php cng mt s tn hiu in p
nu
, v Rf c lp th
NuTrang 18
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
Ng ra s i du Tng tr u vo Zn = Rn, cho mi u vo (V xem nh im t o)
3.6. Mch tch phn:
Hnh: 3.6 Mch ny dng tch phn (c o du) mt tn hiu theo thi gian.
(Trong , Vin v Vout l cc hm s theo thi gian, Vinitial l in p ng ra ca mch tch phn ti thi im t = 0.)
Lu rng cu trc ca mch ny cng c xem l mch lc thng thp, mt dng ca mch lc tch cc.
3.7. Mch vi phn:
Hnh: 3.7 Mch ny ly vi phn (c o du) mt tn hiu theo thi gian.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
(Trong , Vin v Vout l cc hm s theo thi gian) Lu rng cu trc ca mch ny c th xem nh mt mch lc thng thng, mt dng ca mch lc tch cc. 3.8. Mch so snh: Hnh: 3.8 Mch ny so snh hai tn hiu in p, v s chuyn mch ng ra hin th mch no c in p cao hn.
(Trong Vs l in p ngun, v mach s c cp ngun t + Vs v Vs.)
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
CHNG 4: MCH KHUCH I VI SAI - Mt mch khuch i vi sai cn bn trng thi cn bng c dng:
Hnh: 4.1 - C 2 phng php ly tn hiu ra: Phng php ng ra vi sai: Tn hiu c ly ra gia 2 cc thu. Phng php ng ra n cc: Tn hiu c ly gia mt cc thu v mass. - Mch c phn cc bng 2 ngun in th i xng (m, dng) c cc in th cc nn bng 0 volt. - Ngi ta phn bit 3 trng hp: 4.1. Tn hiu vo cng bin v cng pha (v1 = v2 ) : - Do mch i xng, tn hiu ng ra va = vb Nh vy:
va = AC . v1 vb = A c . v2
Trong AC l khuch i ca mt transistor v c gi l li cho tn hiu chung (common mode gain). - Do v1 = v2 nn va = vb. Vy tn hiu ng ra vi sai: va - vb =0. 4.2. Tn hiu vo c dng vi sai: - Lc ny v1 = -v2 (cng bin nhng ngc pha).SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
- Lc : va = -v b. - Do v1 = -v2 nn khi Q1 chy mnh th Q2 chy yu v ngc li nn v = vb. - Ngi ta nh ngha: va - v b = A VS( v1 - v 2 ) Av: c gi l li cho tn hiu vi sai (differential mode gain). Nh vy ta thy vi ng ra vi sai, mch ch khuch i tn hiu vo vi sai (khc nhau hai ng vo) m khng khuch i tn hiu vo chung (thnh phn ging nhau). 4.3. Tn hiu vo bt k: Ngi ta nh ngha: - Thnh phn chung ca v1 v v2 l:
- Thnh phn vi sai ca v1 v v2 l: Vvs = v1 - v2 Thnh phn chung c khuch i bi AC (ng ra n cc) cn thnh phn vi
sai c khuch i bi A vs. Thng thng |A VS| >>|A C|.
4.4. Trng thi mt cn bng: - Khi mch mt cn bng th khng cn duy tr c s i xng. Hu qu trm trng nht l thnh phn chung c th to ra tn hiu vi sai ng ra. * Mt s nguyn nhn chnh: Cc linh kin th ng nh in tr, t in ... khng tht s bng nhau v ng cht. Cc linh kin tc ng nh diode, transistor.. khng hon ton ging nhau. * Bin php n nh: La chn tht k linh kin. Gi dng in phn cc nh sai s v in tr to ra in th vi sai nh. Thit k CMRR (t s nn ng pha) c tr s tht ln.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
Avs Av
CMRR=
Avs: li in p vi sai. Av: li in p ng pha
Thm bin tr R'E cn bng dng in phn cc.
Ch to theo phng php vi mch.
Hnh: 4.2
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
CHNG 5: CC LOI MCH KHUCH I CNG SUT M TN 5.1. OTL (Output Transformer Less) : a. c im : c cp ngun n +Vcc v mass (0V). Tng khuch i cng sut y ko dng transistor b ph i xng nn in th im gia ra loa bng na ngun . Ng ra loa phi ghp vi mt t in Co. b. u im : m thanh t cht lng cao hn do p tuyn tn s rng , Khng b suy gim tn hiu tn s cao do t k sinh ca bin p . Hiu sut cao v khng tn hao trn bin th . Gi thnh r, kch thc nh so vi khi dng bin p ng ra. c. Khuyt im : Phi chnh in th DC ca im gia ra loa bng na ngun cung cp th tn hiu ng ra mi khng b mo . Cp transistor cng sut nu khng phi l cp transistor b ph th d gy mo phi tuyn. Tn hiu ra b mo tn s thp do t Cout gy ra (do t Cout khng th tin ti v cng). 5.2. OCL (Output Capicitor Less ) : a. c im : c cp ngun i xng +Vcc & Vcc nn in th im gia bng 0 . Tn hiu vo mch khuch i trc tip khng cn qua t . Khng c t Co ng ra loa.SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
b. u im: Kh nng chng nhiu tt do dng kiu khuych i vi sai ng vo . p tuyn tn s rng do khng dng t v bin th ng ra. c. Khuyt im : Cn dng 2 ngun. Tn hiu ra loa trc tip nn in th DC im gia ng ra khc 0V s gy chy loa v vy cn phi c mch bo v loa. 5.3. BTL (Bridge Transistor Line Out) : a. c im :BTL c hai loi : Dng ngun n l mch ampli ghp t hai mch khuch i cng sut OTL. Dng ngun n l mch ampli ghp t hai mch khuch i cng sut OCL. b. u im : Cho ra cng sut ln(gp 4 ln so vi OTL hay OCL) khi s dng vi ngun in p thp hoc dng cho cc Ampli c cng sut rt ln t 500W n vi nghn Walt. c. Khuyt im : Gi thnh cao. Tn hiu ra d b mo hai mch khuch i khng ging nhau. D b chy nu in th im gia khng bng 0.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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GVHD: Nguyn Vn An
PHN II: THI CNG 1.S KHI:
Tng Vi Sai
Tng Thc
Tng Cng Sut
Loa
Khi Ngun ( 35 V 42 V) DC
Mch Tin Khuch i OPAMP 2.S NGUYN L:C 11 0 0 u F+ 0 V 1 +
Tn Hiu Vo ( 1- 5 mV )
R1 K
1 R
C 2
33 3
V
i n
(
C
L
2
)
R
5
C
4
4
4 7 K D
1 0 2 Z 1 5 V +
1 0 0 u F
1 K 4 7 K 7
0 V 1
4 . 7 u F
6 5
+
V
i n
(
R
4) 7 K
1 0 2 D Z 1 5 V + 4 7 u F
8
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
+
3
+
-
4 . 7 u F
2
4 7 K 1
4 . 7 u 4 F7 K
3 K
R3 4
C
8+
O1
U
T
(
L
)
( 1 / 2 ) 4 5 5C 8
R
6
5
R1
31 5 1
4 . 7 u F
C
6 K
6
8
C
7
V
(
-
)
4 7 u F
03 3
HNH II.1: S mch khuych i thut ton 2 knh
+
+ 4 . 7 u 4 F7 K 3 K 3 + 4 . 7 u F 1 1 5 1
O1
U
T
(
R
)
( 1 / 2 ) 4 5 5 8 6 K 8
+
V
(
+
)
0
Trang 26
Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
R2 K
1 42
VR 26 . 8
+
C
31 5 1 Q 42 3 8 3
IN
P U T1 3 9 K 2 2 1 C 1 8 1 5 x 2
QA 1
30 1 3
C
QD
57 1 8
R
1
C
1Q
1
Q
2 R
C 32 K
2
3
3
1
N
4
0 0 7
0
1
R1
45 0
R
5- 5 W
0 . 3 3
R+
73 9
K
C1
40 0
Cu F 1
50 4
R1
95 0
R1
6K
R1 0
8 0
R
1 0 0- 5
SW
P
E
A
K
E
R
0 . 3 3
0 2 N Q R6
5 5 5 1 6
x 2 Q1N 4148 x3
Q Q 7 1 22 0 A 1
96 8 8
80 1 3
B
1 18 0
R2
C
6
1
5 1
R6
1 3. 8
V
-
HNH II.2: S mch cng sut mt knh
3. NGUYN L HOT NG: 3.1 Khi ngun: Cung cp ngun DC vi mc in p n nh l 42V cho ton b mch hot ng. 3.2 Tng tin khuch i: L tng u tin tn hiu i vo, c nhim v bin tn hiu c mc in th thp thnh tn hiu cng cao hn ghp vo tng khuych i in th (y l mch khuch i bin in th thnh cng ). Do tn hiu phi trung thc, ngun cp in phi c lc k khi nh hng ti tn hiu ti tng ny. 3.3 Tng thc:SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
Tng ny c chc nng nhn tn hiu t tng nhp vo, chuyn i tn hiu t ng ra tng nhp thnh tn hiu c mc in th cao hn cung cp cho tng khuch i cng sut. 3.4 Tng khuch i cng sut: Nhn tn hiu c in p cao t tng thc ri khuch i v cung cp dng m tn c cng ln cho loa. c im:
Cp ngun i VCC. sut ca mch ngi ta dng cc cp Darlington.
Tng khuch i cng sut y ko dng Transistor b ph, tng cng in th im gia bng 0. 3.5 Chc nng linh kin: 3.5.1 Chc nng linh kin ca tng tin khuch i: R1,C1 dng lc tn hiu vo. Q1,Q2 l cp vi sai dng n dng, cung cp cho tng thc. Q6 cung cp dng cho cp vi sai. 3 Dit 4148 ghim p cp cho Q6, Q7. 3.5.2 Chc nng linh kin ca tng thc T C2 n nh phn cc CB cho Q3. Q3, Q7 cung cp ngun dng ln cho tng cng sut. R2, R12 n nh nhit cho Q3, Q7. 3 Dit 4007 ghim p cp cho Q3, Q7 3.5.3 Chc nng ca cc linh kin ti tng khuch i cng sut : R4, R5, R9, R10: n nh nhit cho Q4, Q5, Q8, Q9. Q4, Q8: :l cp transistor b ph cng sut nh, ghp Darlington vi Q5 v Q9 nhm tng h s khuch i dng in. Q5, Q9: L cp Transistor b ph cng sut ln.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
4. S MCH IN:
5. LP RP: 5.1 Cc thit b s dng: a/ S nguyn l. b/ Linh kin lp mch. c/ Mch in. d/ Ngun cung cp. e/ Loa v dy tn hiu. f/ ng h o (VOM). g/ M hn v ch hn. 5.2 Qu trnh thi cng: Phn tch s nguyn l. Tin hnh gia cng mch. Lp rp v kim tra hot ng ca mch
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
6. KT QU: Mch lp rp xong, sau qu trnh tinh chnh, mch hot ng tt v n nh.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
KT LUN
n 1 l mt bi tp ln, mt th thch i vi sinh vin, tuy nhin vi n ny gip cho sinh vin vn dng mt cch c th kin thc ca mnh hc mt cch sng to v lm quen dn vi cch hc t nghin cu, hc tp v lm vic vi nhm nghin cu v thc hin n mt cch tt nht. Hn th na, n 1 cn gip sinh vin quen dn vi cch lm cc n tt nghip sau ny. Xin chn thnh cm n s nhn xt nh gi ca cc thy c v s hng dn tn tnh ca thy Nguyn Vn An.
T mch cng sut ( 80 100 W ) trn, c th ci tin, pht trin v thay th linh kin. nng cao cng sut. p ng c nhng cng sut khc nhau m ta mong mun. Mch khuch i cng sut m tng trn c th rp thm mch lc m sc ( Bass Treble) trc ng vo. c m thanh ng ra hay hn.
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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Mch Khuch i Cng Sut m Thanh n I
GVHD: Nguyn Vn An
TI LIU THAM KHO1. Phan Tn Un Ampli hifi (50W n 550W) Tp 1, Tp 2 Nxb S GD&T TP H Ch Minh, 2001. 2 Nguyn Tn Phc Mch in t Nxb Hng c, 2008 3. Nguyn Tn Phc Gio trnh linh kin in t Nxb Hng c, 2008 4. L Phi Yn-Lu Ph-Nguyn Nh Anh K thut in t Nxb HQG TPHCM, 2005 V mt s Website: 1. alldatashet.com 2. dientuvietnam.net 3. biendt.biz
SVTH: Phm Hu Hip Thi Quc Dn - Lp:CDDT 9B
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