thiet ke mach cam bien khoi p1 6926

8/8/2019 Thiet Ke Mach Cam Bien Khoi p1 6926

1/16

TI

THI T K M CH I N T T NG T :

M CH C M BI N KHI, T N I CNG C NG. KHI C NG I HT THU C TRONG PHNG TH CHUNG REO

L I NI U

Ngy nay, con ng i cng v i nhngng dng ca khoa hc k thut tintin ca thgi i, chng ta vang ngy mt thayi, vn minh v hin i h n.Spht trin ca k thut in t to ra hng lot nhng thit b v i cccim ni bt nhschnh xc cao, tc nhanh, gn nhl nhng yu tr t cnthit gp phn cho hot ng ca con ng i t hiu qungy cng cao h n.

in t ang tr thnh mt ngnh khoa hc a nhim v. in t png c nhng i hi khng ngng ca cc ngnh, l nh vc khc nhau chon nhu

cu thit yu ca con ng i trong cuc sng hng ngy. Mt trong nhngng dngca r t quan tr ng ca ngnh cng ngh in t l cc mch cm bin v i cc linhkin tch h p cao. Mch cm bin c ng dng r t nhiu trong cng nghi p vcc l nh vc khc trong cuc sng v i nhng thit b iu khin txa r t tinh vi vt c nng sut, kinh ttht cao .

Xut pht tnhngng dng , chng em thit k mt mchng dngnh l mch cm bin khi. V th i gian, ti liu v trnhcn hn chnnvic thc hin n cn nhiu thiu st Knh mong nhn c sch dn vgp tn tnh ca tt cqu thy cng cc b


2/16

M C L C

Trang

L I M U2 PH N THI T K CHNH

PHN I:NGUYN TC THIT K V S KHI...4I) Nguyn tc thit k ..........................................................5II) S khi .......................5

PHN II:S NGUYN L, CH C NNG T NG KHI7 I) Chc nng tng khi.7II) S khi ton mch...8III) Nguyn l hot ng...9

PHN III: CC LINH KIN S DNG TRONG MCHI) in tr 11

II) T in.12III) Transistor13IV)iot-led...14V) IC LM1801...15VI)iot 1N4004....16


3/16

VII) TIC 106M...17VIII) LDR ..20IX) Chung v HP126

PHN IV:NH GI U NH C IM CA MCH .26PHN V:K T LUN .28

PHN I : NGUYN TC THIT K V S KHI

I) NGUYN TC THIT K Mch cm bin khi th ng c sdng trong cc hthng bong tin tin.

Hu ht cc thit b ny sdng chuyn nghi p kh-d, ion ha phng hoc cc yutphng xnhcc cm bin.C hai cch c bn thit k bcm bin khi.

Cch thnht sdng nguyn tc ion ha. Ng i ta sdng mt l ng nhcht phng x ion ha trong bcm bin. Khng kh b ion ha sdn in v tothnh mt dngin chy gia hai cc c n p in. Khi cc phn tkhi ltvo khu vc cm nhn c ion ha slm tng in tr trong bung cm nhn vlm gim lung in gia hai cc. Khi lung in gim xung t i mt gi tr noth bcm bin pht hin v pht tn hiu bong.

Cch thhai sdng cc linh kin thu pht quang. Ng i ta dung linh kin phtquang (LED, LED hng ngoi ) chiu mt tia nh sang qua vng bo veejvaof mt linh kin thu quang (photo diode, quang tr , photo transistor).


4/16

Khi msxutche ch

gim xng.

Trokh thv dtcm bi

II) S

t vchyhin khin hoc l

ng t i m

g hai ccc thi v lc thi. L n khi v

KH

y ra ho i mt gim c

t gi tr n

ny th p t. Cn

i dngcsdng b

MCH C

khi c ncao. Khingnh

o th

ng phcch th im ny phn thu

M BI N

i ht thc chy, k sng chi

cm bi

p thnhtai tuy t nchng em pht chn

KHI :

uc trongi i nga

u vo linh

n spht

nhy h ny h n nchn ccl LDRs

phng thg qua vkin thu.

in v ph

v hiu qng linhhaithi

v mt L

khu vcg bo v hi c ng

t tn hiu

h n nhin dkit k mcD

bo

ngm


5/16

PHN II: CH C NNG T NG KHI, S NGUYN L V NGUYN L HOT NG

I) CH C NNG TON KHI1) Khi cm bin : c nhim vbin i tn hiu khi thnh tn hiu in, trong

phn thit k ny ta dng quang tr . Nh ta bit hot ng ca quang tr l: khic nh sang chiu voin tr ca n gim i ng k so v i khi khng c chiusng.

2) Khi n nhin p ngun Khi ngun ly ngun AC_ 220V t in l i gianh,dng bin thhp

xung 12Vol_AC, khi qua cu chnh lu c DC_ 12V, dng IC 7805p cungc p 2 mc in p cho ton mch l +12vol v +5vol.

Hoc ta cng c thly tr c ti p sc in thoi dng lm ngun cho mch


6/16

3) KhM

va

Tr ny baotham c 4) Kh II) S

S

khuychch khuyca tn hiu

ng tigm khiiu so sn

bo n

NGUY

nguyn l

i :h i c niu ch

y, mchkhuych

h tn hiu

: to ra

N L :

ton m

im vk ua khi b

khuychi thut t

u vo v

m thanh b

h :

uych io ng

i c sn v b i tn hiu

o ng

tn hiu pht tn h

dng l Io snh soin mt

in tb iu bo

C LM180snh v ihiu.

m bin k ng.

. IC LM1ai in p

hi

01


7/16

III) NGUYN L HOT NG :

LM1801 l mt IC cng dng c bit, c thit k c bit cho cc my dkhi, cung c p cho chng ta xy dng mch ny bng cch sdng sl ng tithiu ca cc thnh phn. N bao gm mt trong nhng ngun cung c p zener ni b, hai k t qu u rain p tham chiu, mt in p so snh, vin pu ratransistor l 500mA.

Vi mch c k t ni v i ngun in tr c ti p. iot D1 chnh lu ngun inxoay chiu vin tr R7 lm gim nn mc m cc mch c thhot ng v it in C2n nh in p v zener bn trong ICiu chnh n.

Hai LDRsng nht c ni theo kiu cu sao cho k t ni ny bo vv ngnchn nhng sthayi nhit v ha gi nhng hiung tcng ln mch.

V vy R13 LDR v LED phi c t theo mt cch sao cho khi c cc htkhi thuc xm nh p vo n stcng ln bmt LDRs v lm gim nh sngtrn LDR ng th i lm thayi in tr ca n. Mt khc R12 LDR v LED phi c t lin k nhau v khng c khng kh lu thng xy ra. Nhvy khi thucl skhng c gynh h ng n R12 vin tr ca n khng b bin i. Cchtt nht lmiu , lt R12 v LED trong mt h p ring bit.

P1 lin p hiu chun. HP1 l mt m thanh bong my phtin. Dngin u ra tcng ln hthng bong bn ngoi.

Khi thc hin so snh v pht hin schnh lch in p gia hai LDRs n tc

ng ln bng bn dn Th1 v k t qul bt u bong,


8/16

PHN IV: CC LINH KIN S DNGTRONG MCH

I) in tr :

in tr l mt linh kin c tnh cn tr dngin v lm mt s chc nngkhc ty vo v tr in tr trong mch in.

Cu to: in tr c cu to t nhng vt liu c in tr sut cao nh lm bng than, magie kim loi Ni-O2, oxit kim loi, dy qun. biu th gi tr intr . Ng i ta dung cc vng mubiu th gi tr in tr .

K hiu:

Hnh dng thc t:


9/16

Cchc tr s in tr 4 vng mu: Gi tr in tr th ng c thhin quacc vch mu trn thnin tr , mi mui din cho mt s. Muen: s0, munu: s1, mu: s2, mu cam: s3, mu vng: s4, mu lc: s5, mu lam s 6, mu tm s7, mu xm: s8, mu tr ng: s9. Nhn trn thnin tr , tm bn c vch mu nm st ngoi cng nht, vch mu

v vch mu thhai, k n c dngxcnh tr sca mu..

Vch thba l vch xc nh nhn t ly tha: 10(gi tr ca mu) . Gi tr ca intr c tnh bng cch ly tr snhn v inhn t lythaGi tr in tr = tr s x nhn t lytha)- Phn cui cng: (khng cn quan tm nhiu)lvch mu nm tch bit v i bavch mutr c, th ng c mu hong kim hoc mubc, dngxc nh sai s ca gi tr intr , hong kim l 5%, bc l 10%. y chng ta sdng iot 1N4004

II) T in:

T in l linh kin c khnng tchin. T in cchin v i dngin mtchiu v cho dngin xoay chiu truyn qua.

T in c chia lm hai loi chnh: loi khng phn cc v loi c phn cc.


10/16

Loic phn cc th ng c gi tr l n h n loi khng phn cc, trn hai chn caloi phn cc c phn bit chn ni m, ni d ng r rng, khi gn tc phn ccvo mch in, nu gn ng c chiu m d ng, tphn cc c thb hv hot

ng sai. Ngoi ra ng i ta cn gi tn t in theo vt liu lm t, v d: tgm,tgiy, tha...Hnh dng: t in c kh nhiu hnh dng khc nhau.

K hiu: c k hiu l C

Biu t ng trn mch in:

n v ca t in

- n v ca t in l Fara, 1 Fara c tr sr t l n v trong thc tng i ta

th ng dng cc n v nhh n nh + P(Pico Fara) 1 Pico = 1/1000.000.000.000 Fara (vit gn l 1pF)+ N(Nano Fara) 1 Nano = 1/1000.000.000 Fara (vit gn l 1nF)+ MicroFarra 1 Micro = 1/1000.000 Fara (vit gn l 1F)


11/16

=> 1F = 1000nF = 1.000.000 Pf

III) Tranzitor:

K hiu : transistor NPN

Transistor PNP

Cu to: b i 2 ti p xc P-N ghp lin ti p gm cc vng bn dn loi P v N x pxen k nhau, vng gia c tnh cht dn in khc v i 2 vng ln cn v c br ngr t mng khong 10A0 m nh to ln ti p xc P-N gn nhau. Nu vng gial N ta c transistor PNP, ng c li nu vng gia l vng P ta c transistor NPN.

IV) Diode_Led

-Diode th ng

-Led quang:quang tr , quang diode v quang transistor, nng l ng ca nh sng chiu vo

Q2

Q1


12/16

cht bn dn v c p nng l ng cho ccin tv t di cm. Ng c bli khi mtin t tdi dn in r t xung di ho tr th spht ra mt nng l ng E=h.f Di dn in Di ha tr Di cm hf. Khi phn cc thun mt ni P-N,in tt

do tvng N xuyn qua vng P v ti h p v i ltr ng (vph ng din nngl ng ta ni ccin ttrong di dn in c nng l ng cao r i xung di hotr - c nng l ng th p v k t h p v i ltr ng), khi ti h p th sinh ra nngl ng.i v i diod Ge, Si th nng l ng pht ra d i dng nhit. Nhng i v i diodcu to bng GaAs (Gallium Arsenide) nng l ng pht ra l nh sng hng ngoi(khng thy c) dng trong cc mch bong,iu khin txa). V i GaAsP(Gallium Arsenide phosphor) nng l ng pht ra l nh sng \vng hay. V iGaP (Gallium phosphor), nng l ng nh sng pht ra mu vng hoc xanh l cy.Cc Led pht ra nh sng thy c dnglmn bo,trang tr Phn ngoica LED c mt thu knht p trung nh sng pht ra ngoi.

c nh sng lin tc, ng i ta phn cc thun LED. Tu theo mc nng l nggii phng cao hay th p m b c sng nh sng pht ra khc nhau squyt nhmu sc ca LED. Thng th ng, LED cin thphn cc thun cao h n itthng th ng, trong khong 1,5 2,8V tu theo mu sc pht ra, mu: 1,4


13/16

1,8V, vkhong

V) LD LDcm bin 10ca n

ng: 2 2,vi mA.iot c s

sRs hayin sng ti0000 ,gim m

5V, cn

dng tro

n tr ph . thng thhng khit cch

u xanh l

g mch n

thuc nh ng gi tr chng b ngt.

cy: 2

y liot

sng. N in tr hch thch

,8V, v d

N4004

tc dna mt Lb i nh s

ng in q

c bitR l r t c

ng th gi

ua LED t

rong mcao, c khitr in tr

i a

cao


14/16

VI) IC LM1801:

LM1801c dng IC, c thit k c bit cho cc my d khi, cung c p

cho chng ti xy dng mch ny bng cch sdng sl ng ti thiu ca ccthnh phn. N bao gm mt trong nhng ngun cung c p zener ni b, hai k tqu u rain p tham chiu, mt in p so snh.

LM1801 thc hin so snh nng l ng th p v i dngin cao ,u ra m vthu tn hiu.

Hin nay ng i ta dng IC LM1801 trong ngnh chto nh: thit b chngtr m, thit b pht hin r r n c, r r kht, nhng mchn p, ngun pin cvn hnh theo diMt sthng schnh ca LM1801:

Dngin cung c p th ng l dng 7A , nhng khi niu khin cng sosnh thin pu ra ca transistor ln t i 500mA

Ti : Rset = 10m, V+= 9v, Ta = 25cR1 + R2 = 10m n nh.


15/16


16/16

thiet ke mach cam bien khoi p1 6926

Documents