Trng i Hc Bch Khoa H Ni

Khoa in T Vin Thng====o0o====

Bo co nhp mn k thut in tGio vin hng dn : Dr Phm Ngc Nam Nhm Sinh vin thc hin : HK : L Ph i Nguyn c Hiu Phm Xun Kin : TVT - 11 - K54H NI 11/2010 1

Lp

Mc lc APHN M U 1. Gii thiu tng 2. Mc tiu nghin cu 3. Phm vi v i tng nghin cu 4. Tiu ch t ra 5. Nhim v

B

QUY TRNH 1. Tm hiu chung v cc linh kin chnh 2. Cc bc thc hin 3. iu kin lm vic

C

KT LUN

1. Kinh nghim v bi hc 2. Hng pht trin ca ti

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LI CM N

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A M U 1. Gii thiu v tng Hin nay cc mch in t s dng n led nhp nhy lm bin qung co,trang tr, chiu sng .vi th loi v kch thc xut hin ngy cng nhiu,thay th cho nhng bin qung co v cc mch chiu sng thng thng trc kia.n led lm cn nh v ng ph ca chng ta ban m tr nn p hn Chng ta c th bt gp mi ni trn ng ti trng v cn rt nhiu li ch khc m n led na Th nhng bao gi chng ta t t ra cc cu hi :

1. Mch n gm nhng linh kin g? 2. Mch n hot ng ra ra sao cha? 3. Nguyn l hot ng nh th no? 4. ??? 5. Chnh v vy nhm chng ti chn ti lm bi tp ln ln ny.

6. mi ngi c th hiu c nhng iu nhm ti s a ra cc mch n led daong m vng cng nh nguyn l hot ng, lm nn tng gip cc bn hiu c nhng mch n nhp nhy phc tp sau ny ni chung cng nh mch in t ni ring.

2. Mc tiu nghin cu1. 2. 3. 4. Nhn bit cc linh kin Hiu c nguyn l mch a hi n gin, cc cng on thit k mt mch in t Lm quen v s dng cc cng c h tr mch Nng cao k nng mm, tng am m vi ngnh in

3. Phm vi v i tng nghin cuCc linh kin in t, mch in t v Led Phn mm v mch Orcad, phn mm m phng Proteus, Powerpoint

4. Tiu ch t raMch c kch thc nh gn, hot ng tt Mch to dao ng m vng gm 10 led Cc n Led sng thay phin lin tc 3

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Gi thnh r, thi gian nghin cu, lp rp nhanh

5. Nhim v thc hin nhng mc tiu , nhm phn cng cc bn vi nhng nhim v sau: Thnh vin L Ph i Phm Xun Kin Nguyn c Hiu Nhim v Tm hiu mch, mua sch hng dn, phn mm m phng Nghin cu mch, cch lp rp Mua linh kin cn thit, m phng trn phn mm

Nhm trng : L Ph i

B QUY TRNHI. Tm hiu chung v cc linh kin chnh1. N LEDLED vit tt t ch Light Emitting Diode. n LED trng khc vi cc n LED mu c bit n t nc ta qua cc bng n nh nhiu mu: xanh, trng, , vng... gn trn cy Noel trong ma Ging sinh, cc bng hin th giao thng nm gn cc trm thu ph trn cc tuyn ng ln, cc mn hnh phng khng l trn nc nh cc bit th th hoc trong TPHCM. Cc hin th mu bng n LED cng xut hin khp cc ca hiu, ph phng, siu th, tim n cc TP ln trong nc. S dng n LED - i t pht quang chiu sng ang c a chung trong trang tr ni tht n LED thay th n si t v n hunh quang bi nhng u im nh tit kim nng lng, tui th cao, kch c nh, nhit nng sinh ra trong qu trnh hot ng khng ng k, hot ng tt trong iu kin nhit thp, khng s dng thy ngn ging nh cc loi bng hunh quang thng thng. Trong tng lai, bng n in s khng ch c vai tr chiu sng, m cn c th gip chng ta truy cp Internet, giao tip vi cc thit b in t trong nh. Cc thit b iu khin t xa ang s dng tia hng ngoi giao tip vi TV,

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u DVD. Vic bin nhng chic n bn v n trn thnh im truy cp Internet khng dy c th gip bn lt web mi ni..

2. IC 555IC thi gian 555 c du nhp vo nhng nm 1971 bng cng ty Signetics Corporation bng 2 dng sn phm SE555/NE555 v c gi l my thi gian v cng l loi c u tin. N cung cp cho cc nh thit k mch in t vi chi ph tng i r, n nh v nhng mch t hp cho nhng ng dng cho n n v khng n nh. T thit b ny c lm ra vi tnh thng mi ha. 10 nm qua mt s nh sn sut ngng sn sut loi IC ny bi v s cnh tranh v nhng l do khc. Tuy th nhng cng ty khc li sn sut ra nhng dng ny Cc dng hnh dng chn ca 555 trong thc t:

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Hnh dng ca 555 trong hnh 1 v hnh 2. Loi 8 chn hnh trn v loi 8 chn hnh vung. Nhng th trng Vit Nam ch yu l loi chn vung.

IC 555 n tng ng vi hn 20 transitor , 15 in tr v 2 diode v cn ph thuc vo nh sn xut. Trong mch tng ng trn c : u vo kch thch , khi so snh, khi iu khin chc nng hay cng sut u ra.Mt s c tnh na ca 555 l : in p cung cp nm gia trong khong t 3V n 18V, dng cung cp t 3 n 6 mA. Dng in ngng xc nh bng gi tr ln nht ca R + R . in p 15V th in tr ca R + R .phi l 20M Tt c cc IC thi gian u c 1 t in ngoi to ra 1 thi gian ng ct ca xung u ra. N l mt chu k hu hn cho t in (C) np in hay phng in thong qua mt in tr R. Thi gian ny n c xc nh v n c th tnh c thong qua in tr R v t in C IC 555 gm c 8 chn. + Chn s 1(GND): cho ni GND ly dng cp cho IC hay chn cn gi l chn chung. + Chn s 2(TRIGGER): y l chn u vo thp hn in p so snh v c dng nh 1 chn cht hay ng vo ca 1 tn so p.Mch so snh y dng cc transitor PNP vi mc in p chun l 2/3Vcc. + Chn s 3(OUTPUT): Chn ny l chn dng ly tn hiu ra logic. Trng thi ca tn hiu ra c xc nh theo mc 0 v 1. 1 y l mc cao n tng ng vi gn bng Vcc nu (PWM=100%) v mc 0 tng ng vi 0V nhng m trong thc t mc 0 ny ko c 0V m n trong khong t (0.35 ->0.75V) . + Chn s 4(RESET): Dng lp nh mc trng thi ra. Khi chn s 4 ni masse th ng ra mc thp. Cn khi chn 4 ni vo mc p cao th trng thi ng ra ty theo mc p trn chn 2 v 6.Nhng m trong mch to c dao ng thng hay ni chn ny ln VCC. + Chn s 5(CONTROL VOLTAGE): Dng lm thay i mc p chun trong IC 555 theo cc mc bin p ngoi hay dng cc in tr ngoi cho ni GND. Chn ny c th khng ni cng c nhng m gim tr nhiu ngi ta thng ni chn s 5 xung GND thng qua t in t 0.01uF n 0.1uF cc t ny lc nhiu v gi cho in p chun c n nh. + Chn s 6(THRESHOLD) : l mt trong nhng chn u vo so snh in p khc v cng c dng nh 1 chn cht. + Chn s 7(DISCHAGER) : c th xem chn ny nh 1 kha in t v chu iu khin bi 6

tng logic ca chn 3 .Khi chn 3 mc p thp th kha ny ng li.ngc li th n m ra. Chn 7 t np x in cho 1 mch R-C lc IC 555 dng nh 1 tng dao ng . + Chn s 8 (Vcc): Khng cn ni cng bt l chn cung cp p v dng cho IC hot ng. Khng c chn ny coi nh IC cht. N c cp in p t 2V -->18V (Ty tng loi 555 nh thp nht l con NE7555)

3. IC 4017IC m thp phn S chn:

IC m thp phn 4017 c 10 ng ra mc cao. Ch c mt ng ra c kch mc cao ti mt thi im. Bn c th thy c ra ng ra 10 output s mc cao cho lt m 0 > 4 v mc thp khi m 5 > 9.

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II.

Cc bc thc hinBc 1: xc nh yu cu ca mch Bc 2: Tm hiu nguyn l mch Bc 3: Lp rp v kim tra mch Bc 4: Hon tt v vit bo co

1. S NGUYN L8

2. S LP T

III. iu kin lm vicNhm thc hnh gm 3 ngi, c nhm trng phn cng nhim v c th. Cc dng c phc v cho mch Led nhp nhy 3 nhnh a hi: -

M hn, km, thic hn, nha thng10 bng Led, 4 in tr 100

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1 IC 555, 1 IC 4017 1 t ha 100F, 1 t thng 104F

1 ngun 5V, 1 bng mch va dy dn Tt c u c mua mi. Mt s kh khn: Do ln u th nghim lm mt mch in nn c nhm cha c kh nng lm mch nhanh, nhiu minh kin phi tm hiu trong thi gian kh nhiu, cc linh kin cho mch d hng a im t mch in xa, chn linh kin khng kht vi mch do li k thut

C. KT LUNI. KINH NGHIM, BI HCMch Led dao ng m vng, cc linh kin cn thit d tm kim. Nguyn l mch r rng, d hiu, d lp rpQua qu trnh lm mch cho ta thm kinh nghim cch hn chn linh kin cho bng p, cch s dng phn mm Orcad v mch mt cch hp l nht. Ngy nay n LED c ng dng Qung Co. V cuc cch mng v n LED s nhanh chng thay i nhng bin qung co, hp n, n neon sign c k. V cc mch v n LED s ngy cng mt pht trin.9

II. HNG PHT TRIN CA TI.Mch n m vng c lp hot ng theo yu cu, ta c th lp thnh h thng n vi nhiu bng Led theo mt hnh dng c th nht nh, v trn nhng mch , to hiu ng tt ta c th dng thm cc phn mm h tr nh chng trnh KeilC, chng trnh cho mch np vi cc hiu ng rt hu ch, p mt . T vic tm hiu IC 555 v 4017 nhm chng ta c thm c s thc hin cc mch sau:a ) Mch bo ng m thanh dng SCR

b) Mch bo ngun in

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c) mch led nhp nhy hnh tri tim

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D LI CM NEm xin chn thnh cm n cc thy c trong B Mn Nhp Mn K Thut in T, Khoa in T Vin Thng to iu kin cho em thc hin ti bi tp ln ny. Xin cm n thy Phm Ngc Nam, ngi tn tnh hng dn, ch bo cho nhm em trong sut thi gian thc hin ti. Trong thi gian lm vic vi Thy, em khng nhng hc hi c nhiu kin thc b ch m cn hc c tinh thn lm vic, thi nghin cu khoa hc nghim tc ca Thy.

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Mc d rt c gng hon thin bi tp ln vi tt c kin thc c hc v s n lc ca bn thn v c nhm, nhng chc chn khng th trnh khi nhng thiu st. Knh mong qu Thy C tn tnh ch bo. Mt ln na, em xin chn thnh cm n v lun mong nhn c s ng gp qu bu ca tt c mi ngi.

NHN XT CA GIO VIN

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. . . . . . . . . . .. .. . . H Ni, Ngy .thng .nm 2010 Gio vin (K tn)

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