noi dung

n tt nghip kha 2009-2011

GVHD: Thy Nguyn Hu Phc

Nhn xt ca gio vin hng dn---o0o---

Tp. HCM, ngy . thng . nm 2011 Gio vin hng dn

Nguyn Hu Phc

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Nhn xt ca gio vin phn bin---o0o---

.................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... .................................................................................................................... ....................................................................................................................Tp.HCM, ngy . thng. nm 2011 Gio vin phn bin

Trng Quang Trung

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Li cm nTrong sut thi gian hc tp ti trng Cao ng K Thut Cao Thng, chng em nhn c s ging dy cng nh s ch dn mt cch tn tnh ca qu thy c v nhng kin thc trong hc tp cng nh trong cuc sng. Chng em xin chn thnh cm n qu thy c trong khoa in T-Tin Hc ging dy cho chng em nhng kin thc chuyn mn v to iu kin cho chng em hon thnh tt kha hc, qua gip chng em nh hng c trong vic la chn v thc hin ti LCH VN NIN trong kh nng ca mnh. Chng em cng xin chn thnh cm n Thy Nguyn Hu Phc, tn tnh theo di, gip v hng dn chng em trong sut thi gian chng em thc hin v hon thnh n ny. Nhm sinh vin thc hin NG QUC KHNHON VN LN NGUYN DUY C LIN

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Li ni uNgy nay, khoa hc cng ngh t c mt trnh pht trin rt nhanh v mnh m, cng vi s pht trin ca cc nghnh k thut ni chung v cng ngh in t ni ring. Nhng thnh tu t c cng nh cc ng dng ca cng ngh k thut in t ngy cng c s dng nhiu trong cuc sng hng ngy ca con ngi v trong cc nghnh cng nghip khc. c bit hin nay trong lnh vc vi x l, nhng ng dng ca n mang li hiu qu rt thit thc trong cuc sng nh: quang bo in t, lch vn nin, iu khin tc ng c, h thng m sn phm. Nm dc tm quan trng , chng em quyt nh chn ti LCH VN NIN lm n tt nghip ca mnh. qua th hin c mt phn m hnh ng dng trong cuc sng, trong gia nh Bng nhng kin thc t c trong qu trnh hc tp ti nh trng v nhng tm hiu nghin cu bn ngoi cng vi nhng n lc ca bn thn, mi sinh vin trong nhm ca chng em s c nh gi qua t bo v n ny. So vi thi gian hc tp ti trng th l thnh qu ca qu trnh hc tp cng vi nhng thnh cng ban u trc khi tt nghip ra trng. Nhm chng em c gng n lc ht mnh trong sut thi gian thc hin ti ny nhng vi lng kin thc v thi gian cho php nn n cn nhiu thiu st. Nhm chng em mong nhn c nhiu s nhn xt v kin ng gp ca qu thy c v cc bn v ti ny cng nh hng m rng, pht trin ti hon thin hn. Nhm chng em xin chn thnh cm n.

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Mc LcNhn xt ca gio vin hng dn...........................................................Trang Nhn xt ca gio vin phn bin........................................................................ Li cm n............................................................................................................ Li ni u............................................................................................................ Mc lc.................................................................................................................. Chng dn nhp:..............................................................................................7 1.1.t vn ...............................................................................................7 1.2.Cc yu cu t c v hn ch ca ti............................................7 1.3.Mc ch nghin cu..............................................................................8 1.4.i tng nghin cu, ng dng v hng pht trin ti...................8 Chng 2: Gii thiu mt s linh kin c s dng trong mch.......................9 2.1.Gii thiu v Pic.....................................................................................9 2.1.1.Tng quan v h vi iu khin.......................................................9 2.1.1.1.Mt s c tnh ca vi iu khin Pic.......................................9 2.1.1.2.Nhng c tnh ngoi vi.........................................................10 2.1.1.3.c im v tng t.............................................................11 2.1.1.4.Cc c im c bit ca vi iu khin Pic...........................11 2.1.1.5.Cng ngh CMOS..................................................................12 2.1.2.Gii thiu v Pic16f8xx v Pic16f877A.......................................12 2.1.2.1.Cc c tnh ngoi vi bao gm...............................................13 2.1.2.2.S lc v vi iu khin Pic16f877A.....................................14 2.1.2.3.Cu trc phn cng ca Pic16f877A......................................18 2.1.2.4.Mt s ch c bit ca vi iu khin Pic16f877A............19 2.1.2.4.1.Dao ng..........................................................................19 2.1.2.4.2.Reset.................................................................................21 2.1.2.4.3.MCLR...............................................................................21 2.1.2.4.4.Interrups............................................................................22 2.1.2.5.T chc b nh.......................................................................23 2.1.2.5.1.B nh chng trinh.........................................................23 2.1.2.5.2.B nh d liu..................................................................24 2.1.2.6.Cc thanh ghi chc nng c bit...........................................31 2.1.2.6.1.Thanh ghi trng thi(Status Register)...............................31 2.1.2.6.2.Thanh ghi ty chn(Option Register)...............................32 2.1.2.7.Khi qut chc nng cc Port trong vi iu khin Pic............33 2.1.2.7.1.PortA v thanh ghi TrisA..................................................34 2.1.2.7.2.PortB v thanh ghi TrisB..................................................36 2.1.2.7.3.PortC v thanh ghi TrisC..................................................38 SVTH: KHNH-LN-LIN N :LCH VN NIN5



2.1.2.7.4.PortD v thanh ghi TrisD..................................................39 2.1.2.7.5.PortE v thanh ghi TrisE...................................................40 2.1.2.8.B nh thi ca Pic16f877A.................................................41 2.1.2.8.1.B nh thi Timer0.........................................................41 2.1.2.8.2.B nh thi Timer1.........................................................43 2.1.2.8.3.B nh thi Timer2.........................................................45 2.1.2.9.Ch diu ch xung PWM...................................................46 .................................................................................................. 2.1.2.10.Module ADC........................................................................48 2.1.2.10.1.Gii thiu Module ADC 10 bit.......................................48 2.1.2.10.2.Cc thanh ghi iu khin.................................................48 2.1.2.10.3. La chn xung Clock cho bin i ADC.......................51 .................................................................................................. 2.2 IC n p 7805.......................................................................................52 2.3.Chip DS1307........................................................................................53 2.4.Diode....................................................................................................59 2.4.1. Diode chnh lu.....................................................................59 2.4.2.diode pht quang(led n)......................................................60 2.4.3 Led 7 on..............................................................................60 2.5.in tr. ...............................................................................................62 2.6.T in. . ...............................................................................................63 2.7.Transistor..............................................................................................65 Chng 3:S nguyn l cc khi trong mch...............................................77 3.1.S nguyn l mch Pic16f877A v DS1307....................................77 3.1.1.Lu gii thut Lch Vn Nin..........................................78 3.1.2.S khi chung.......................................................................79 3.2. S khi hin th...............................................................................80 3.3.S mch ngun................................................................................81 Chng 4:Tng quan v ngn ng lp trnh CCS.............................................82 Code chng trnh Lch Vn Nin.............................................................83 Chng Tng Kt:............................................................................................94 Ti liu v cc trang Web tham kho:............................................................95

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CHNG 1: DN NHP1.1. t vn : Vi nhng thnh tu v khoa hc k thut cng nh nhu cu ca con ngi ngy cng cao. V vy i hi nhiu ng dng ca khoa hc k thut vo cc ngnh cng nghp ni chung v k thut in t ni ring c ng dng vo cuc sng. N gip cho ngnh in t ngy cng pht trin, ng thi gip cho cuc sng ca con ngi ngy cng nng cao hn. Mt trong cc ng dng c s dng rng ri trong cuc sng hng ngy, trong cc thit b trong gia nh. Trong giai on hin nay, vi s pht trin vt bc ca cng ngh ch to, hng lot cc loi IC mi ra i v pht trin. Nhng loi IC ny x l nhanh hn rt nhiu so vi cc IC trc v c bit chng ta c th ghi/xa d liu 1 cch d dng.V th, n c s dng nhiu trong cc thit b in-in t. Vi s ra i ca cc dng IC mi lm thc y s pht trin ca nhng IC thi gian thc nh: DS1307, DS12887Bn cnh s pht trin ca khoa hc k thut gp phn nng cao i sng con ngi.Cng chnh v th m mi ngi cn phi bit chnh xc ngy, gi thu xp vic lm, hc tp cho hp l. Xut pht t tht tin nhm chng em quyt nh chn ti Lch Vn Nin nhm p ng nhu cu ham mun hc hi ca bn thn, cng nh gp phn nng cao gi tr ca nhng mch in t ng dng trong cuc sng. 1.2. Cc yu cu cn t c v hn ch ca ti: Cc yu cu t c: Th ( trong tun ),gi, pht, ngy, thng, nm ( dng lch ). Ci t c thi gian, cp nht thi gian thc thng qua DS1307 Cha hin th c ngy, thng, nm ( m lch )

Hn ch ca ti: 1.3. Mc ch nghin cu:

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Trong qu trnh nghin cu v thc hin ti ny gip cho ngi thc hin: -

Tng kh nng t hc, t nghin cu v gii quyt vn . Tip xc trc tip vi thc t, nng cao kinh nghim ngh nghip chuyn ngnh. Phi nm vng v vn dng nhng kin thc chuyn ngnh, tm hiu

nghin cu ti liu qua sch v, gio trnh nc ngoi v cc mch in v m hnh thc t lin quan thi cng phn cng. 1.4. i tng nghin cu, ng dng v hng pht trin ca ti: Lp trnh vi x l cho hot ng ca mch nn i tng nghin cu chnh l vi iu khin Pic16F877A, IC s cho vn iu khin v hin th. ti ny c ng dng rng ri v ph bin trong cuc sng con ngi. Hng pht trin ca ti l xem xt nghin cu cc ng dng trong thc t c th m rng v pht trin ti.

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Chng 2:

GII THIU MT S IC C S DNG TRONG MCH2.1. Gii thiu v PIC: 2.1.1. Tng quan v h vi iu khin: Dng PIC u tin l PIC1650 c pht trin Microelectronics Division thuc General_Instrument. PIC bt ngun t ch vit tc ca Programmable Intelligent Computer (My tnh kh trnh thng minh) l mt sn phm ca hng General Instruments t cho dng sn phm u tin ca h l PIC1650. Lc ny, PIC 1650 c Pic l mt ho vi iu khin RISC c sn xut bi cng ty Mirochip Technology. dng giao tip vi cc thit b ngoi vi cho cc my ch 15 bit CP1600, v vy, ngi ta cng gi PIC Peripheral Interface Controller (B iu khin giao tip ngoi vi). CP1600 l mt CPU tt, nhng li km v cc hot ng xut nhp, v vy PIC 8_bit c pht trin vo khong nm 1975 h tr hot ng xut nhp cho CP1600. PIC s dng microcode n gin t trong ROM, v mc d cm t RISC cha c s dng thi by gi, nhng PIC tht s l mt vi iu khin vi kin trc RISC, chy mt lnh mt chu k my (4 chu k ca b dao ng). Nm 1985 General Instruments bn b phn vi in t ca h, v ch s hu hy b hu ht cc d n lc qu li thi. Tuy nhin, PIC c b xung EPROM to thnh mt b iu khin vo ra kh trnh. Ngy nay rt nhiu dng PIC c sn xut vi hng lot cc module ngoi vi tch hp sn (nh USART,PWM,ADC.), vi b nh chng trnh t 512 Word n 32k Word. 2.1.1.1.Mt s c tnh ca Vi iu khin PIC: Hin nay c kh nhiu dng PIC v c rt nhiu khc bit v phn cng nhng chng ta c th im qua mt vi nt sau:

8/16 bit CPU, xy dng theo kin trc Harward c sa i. Flsah v ROM c th ty chn t 256 byte n 256 Kbyte. N :LCH VN NIN9

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Cc cng xut/nhp (I/O) mc logic thng t 0V n 5.5V, ng vi 8/16 bit timer. Cc chun giao tip ni tip ng b, khung ng b USART. B chuyn i ADC Analog_to_digital converters, 10/12 bit. B so snh in p. Cc module Capture/Campare/PWM. LCD. MSSP Peripheral dng cho cc giao tip IC2,SPI. B nh ni EPROM-c th ghi/xa ln ti mt triu ln. Moudle iu khin ng c,c encoder. H tr giao tip USB. H tr giao tip CAN. H tr giao tip LIN. H tr giao tip IRDA. Mt s dng c tch hp 7675b RF (PIC16f639,v RFPIC). KEELOQ m ha v gii m. DSP nhng tnh nng x l tn hiu s (dsPIC) c im thc thi tc Ch gm 35 lnh n. Tt c cc lnh l mt chu k ngoi tr chng trnh con l hai chu k. Tc hot ng: DC_20MHz ng vo xung clock. DC_200ns chu k lnh.

logic 0 v 1.

cao ca RISC CPU ca h vi iu khin PIC16F87XA.

2.1.1.2. Nhng c tnh ngoi vi: Timer0 : 8_bit nh thi/m vi 8_bit, prescaler.

Timer1 : 16_bit nh thi/m vi prescaler, c th c

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tng ln trong sut ch Sleep qua thch anh/xung clock bn ngoi.

Timer2 : 8_bit nh thi/m vi 8_bit, prescaler, Hai module Capture, Compare,PWM: Capture c rng 16 bit, phn gii 12,5ns. Compare c rng 16 bit, phn gii 200ns. phn gii ln nht ca PWM l 10bit.

postscaler.

C 13 ng I/O c th iu khin trc tip. Dng vo v ra ln: 25mA dng vo cho mi chn. 20mA dng ra cho mi chn.

2.1.1.3. c im v tng t: 10 bit, vi 8 knh ca b chuyn i tng t sang s (A/D). Brown_out Reset(BOR). Module so snh v tng t: Hai b so snh tng t.

Module in p chun VREF c th lp trnh trn PIC.

C th lp trnh ng vo n t nhng ng vo ca PIC v trn in p bn trong. Nhng ng ra ca b so snh c th s dng cho bn ngoi. 2.1.1.4. Cc c im c bit ca vi iu khin Pic: C th ghi/xa ti 100.000 ln vi kiu b nh chng trnh Enhanced

Flash.

1000.000 ln ghi/xa vi kiu b nh EPROM. EPROM c th lu tr d liu hn 40 nm. C th lp trnh li di s iu khin ca phn mm. Mch lp trnh ni tip qua hai chn. Ngun n 5V cp cho mch lp trnh ni tip. N :LCH VN NIN 11

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Watchdog Timer (WDT) vi b dao dng RC tch hp sn trn Chip C th lp trnh mng bo v. Tit kim nng lng vi ch Sleep. C th la chn b dao ng. Nng lng thp, tc caoFlash/cng ngh EPROM. Vic thit k hon ton tnh. Khong in p hot ng t 2V n 5,5V. Tiu tn nng lng thp.

cho hot ng ng tin cy.

2.1.1.5.Cng ngh CMOS:

2.1.2 . Gii thiu v PIC16F8XX v PIC16F877A: PIC16F8XX l nhm PIC trong h PIC16FXX ca h vi iu khin 8_bit, tiu tn nng lng thp, p ng nhanh, ch to theo cng ngh CMOS, chng tnh in tuyt i. Bao gm cc nhm sau: PIC16F83 PIC16CR83 PIC16F84 PIC16CR84 Tt c cc PIC16/17 iu c cu trc RICS. PIC16CXX cc c tnh ni

bc, 8 mc ngn xp tack, nhiu ngun ngt tch hp bn trong ln bn ngoi. C cu trc Haward vi cc bus d liu v bus thc thi chng trnh ring bit nhau cho php di mt lnh l 14_bit v bus d liu 8_bit cch bit nhau. Tt c cc lnh iu mt mt chu k lnh, ngoi tr cc lnh r nhnh chng trnh mt hai chu k lnh. Ch c 35 lnh v mt lng ln cc thanh ghi cho php p ng cao trong ng dng. H PIC16F8XX c nhiu tnh nng c bit lm gim cc thit b ngoi vi,

v vy kinh t cao, c h thng ni bt ng tin cy v s tiu th nng lng thp. dy c bn s la chn b dao ng v ch c chn kt ni b dao dng RC nn SVTH: KHNH-LN-LIN N :LCH VN NIN 12



c gii php tit kim cao. Ch SLEEP tit kim ngun v c th c nh thc bi cc ngun reset. V cn nhiu phn khc c gii thiu bn trn s c ni cc phn k tip. PIC 16F877A l dng PIC ph bin nht hin nay ( mnh v tnh nng,

40 chn, b nh cho hu ht cc ng dng thng thng). Cu trc tng qut ca PIC16F877A nh sau: 8 K Flash ROM. 368 Bytes RAM. 256 Bytes EEPROM. 5 ports (A, B, C, D, E) vo ra vi tn hiu iu khin c lp. 2 b nh thi 8 bits (Timer 0 v Timer 2). Mt b nh thi 16 bits (Timer 1) c th hot ng trong ch tit kim nng lng (SLEEP MODE) vi ngun xung Clock ngoi. 2 b CCP( Capture / Compare/ PWM). 1 b bin i AD 10 bits, 8 ng vo. 2 b so snh tng t (Compartor). 1 b nh thi gim st (WatchDog Timer). Mt cng song song 8 bits vi cc tn hiu iu khin. Mt cng ni tip. 15 ngun ngt. C ch tit kim nng lng. Np chng trnh bng cng ni tip ICSP(In-Circuit Serial Programming) c ch to bng cng ngh CMOS 35 tp lnh c di 14 bits. Tn s hot ng ti a 20MHz. 2.1.2.1. Cc c tnh ngoi vi bao gm : Timer0: b m 8 bit vi b chia tn s 8 bit.

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n tt nghip kha 2009-2011 sleep.


Timer1: b m 16 bit vi b chia tn s, c th thc hin chc nng

m da vo xung clock ngoi vi ngay khi vi iu khin hot ng ch Timer2: b m 8 bit vi b chia tn s, b postcaler. Hai b Capture/so snh/iu ch rng xung. Chun giao tip ni tip USART vi 9 bit a ch. CS bn ngoi. Cc c tnh Analog: 8 knh chuyn i ADC 10 bit. Hai b so snh. B nh flash vi kh nng ghi xa c 100.000 ln. Cng nh EEPROM vi kh nng ghi xa c 1.000.000 ln. D liu b nh EEPROM c th lu tr trn 40 nm. Kh nng t np chng trnh vi s iu khin ca phn mm. Np

c chng trnh ngay trn mch in ICSP (In Circuit Serial Programming) thng qua 2 chn. Watchdog Timer vi b dao ng trong. Chc nng bo mt m chng trnh. Ch Sleep. C th hot ng vi nhiu dng Oscillator khc nhau. S chn :

2.1.2.2. S lc v vi iu khin PIC 16F877A:

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Hnh 2.1 S khi PIC 16F877A

S nguyn l:

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Hnh 2.2 S nguyn l PIC 16F877A

Nhn xt: T s chn v s nguyn l trn, ta rt ra cc nhn xt ban u nh sau PIC16F877A c tt c 40 chn 40 chn trn c chia thnh 5 PORT, 2 chn cp

ngun, 2 chn GND, 2 chn thch anh v mt chn dng RESET vi iu khin. 5 port ca PIC16F877A bao gm : PORTA : 6 chn

PORTB : 8 chn

PORT C : 8 chn

PORTD : 8 chn

PORT E : 3 chn Mi chn ca vi iu khin PIC 16F877A c mt chc nng khc nhau. Trong c mt s chn a cng dng: mi chn c th hot ng nh mt ng

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xut nhp hoc l mt chn chc nng c bit dng giao tip vi cc thit b ngoi vi.

Hnh 2.3 S khi cu trc bn trong PIC 16F877A

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2.1.2.3. Cu trc phn cng ca PIC 16F877A: PIC l tn vit tt ca Programmable Intelligent computer do hng General Instrument t tn cho con vi iu khin u tin ca h. Hng Micrchip tip tc pht trin sn phm ny v cho n hng to ra gn 100 loi sn phm khc nhau. PIC16F887A l dng PIC kh ph bin, kh y tnh nng phc v cho hu ht tt c cc ng dng thc t. y l dng PIC kh d cho ngi mi lm quen vi PIC c th hc tp v to nn tn v h vi iu khin PIC ca mnh. Cu trc tng qut ca PIC16F877A nh sau : 8K Flash Rom 368 bytes Ram 256 bytes EFPROM 5 port vo ra vi tn hiu iu khin c lp 2 b nh thi Timer0 v Timer2 8 bit 1 b nh thi Timer1 16 bit c th hot ng c ch tit kim 2 b Capture/ Compare/ PWM 1 b bin i Analog -> Digital 10 bit, 8 ng vo 2 b so snh tng t 1 b nh thi gim st (Watch Dog Timer) 1 cng song song 8 bit vi cc tn hiu iu khin 1 cng ni tip 15 ngun ngt

nng lng vi ngun xung clock ngoi

S khi

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Hnh 2.4 S khi bn trong ca vi iu khin 16F877A 2.1.2.4. Mt s ch t bit ca vi iu khin PIC 16F877: 2.1.2.4.1. Dao ng: PIC16F877A c th hot ng trong bn ch dao ng khc nhau:

LP low-power crystal XT crystal/resonatpor

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HS high-speed crystal/resonatpor RC resistor/capacitor

Hnh 2.5 Cc ch lao ng Trong cc ch LP, XT v HS chng ta s dng thch anh dao ng ni vo cc chn OSC1 v OSC2 to dao ng. Vic la chn t trong dao ng thch anh c la chn da vo bng sau:

Hnh 2.6 Gi tr t trong dao ng thch anh T c gi tr ln s mang tnh n nh ca dao ng nhng lm tng thi gian khi ng.

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Cch tnh chu k my: V d ta s dng thch anh 10Mhz. Khi : Tn s dao ng ca thch anh l Fosc = 10Mhz th chu k dao ng ca thch anh l Tosc = 1/Fosc= 1/10*106(s). Chu k my: T_instruction = 4*Tosc = 4/10*106(s) = 0.4 s = 400 ns 2.1.2.4.2. Reset: PIC16F877A c th b reset bi nhiu nguyn nhn khc nhau: Power-on Reset (POR) MCLR Reset during sleep

MCLR Reset during normal operation

WDT Reset (during normal operation) WDT Wake-up (during sleep) Brown-out Reset (BOR)

Hnh 2.7 Cc ch reset 2.1.2.4.3. MCLR : PIC16F877A c mt b lc nhiu phn MCLR . B lc nhiu ny s pht

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hin v b qua cc tn hiu nhiu. Ng vo MCLR trn chn 4 ca PIC16F877A. Khi a chn ny xung thp th cc thanh ghi bn trong VK s c ti nhng gi tr thch hp khi ng li h thng. (Lu : Reset do WDT khng lm chn MCLR xung mc thp).

Hnh 2.8 Mch MCLR 2.1.2.4.4. Interrupts: PIC16F877A c nhiu ngun ngt khc nhau. y l mt s ngt tiu biu:

Ngt ngoi xy ra trn chn INT. Ngt do Timer0. Ngt do Timer1. Ngt do Timer2.

Ngt do thay i trng thi trn cc chn PortB. Ngt so snh in th.

Ngt do Port song song. Ngt USART.

Ngt nhn d liu. Ngt truyn d liu .

Ngt chuyn i ADC. Ngt mn hnh LCD. Ngt hon tt ghi EEPROM. N :LCH VN NIN 22

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Ngt module CCP. Ngt Module SSP. Cc thanh ghi chc nng ngt: INTCON, PIE1, PIR1, PIE2, PIR2 (cc

thanh ghi ny s c nghin cu cc phn sau).

Hnh 2.9 Cc ch ngt 2.1.2.5. T chc b nh: Cu trc b nh ca vi iu khin PIC16F877A bao gm b nh chng trnh (Program memory) v b nh d liu (Data Memory). 2.1.2.5.1. B nh chng trnh:

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Hnh 2.10 B nh chng trnh PIC 16F877A B nh chng trnh ca vi iu khin PIC16F877A l b nh Flash, dung lng 8K word (1 word cha 14bit) v c phn thnh nhiu trang nh hnh trn. m ha c a ch 8K word b nh chng trnh, thanh ghi m chng trnh PC c dung lng 13 bit. Khi vi iu khin reset, b m chng trnh s tr v a ch 0000h. Khi c ngt xy ra th thanh ghi PC s tr n a ch 0004h. B nh chng trnh khng bao gm b nh Stack v khng c a ch ha bi b m chng trnh. 2.1.2.5.2. B nh d liu: B nh d liu ca PIC l b nh EEPROM c chia ra lm nhiu bank. B nh d liu ca PIC16F877A c chia thnh 4 bank. Mi bank c dng lng 128 byte. Nu nh 2 bank b nh d liu ca 8051 phn chia ring bit : 128 byte u tin thuc bank1 l vng Ram ni ch cha d liu, 128 byte cn li thuc bank 2 l cng cc thanh ghi c chc nng c bit SFR m ngi dng khng c

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N :LCH VN NIN 24



cha d liu khc trong y th 4 bank b nh d liu ca PIC16F877A c t chc theo cch khc. Mi bank ca b nh d liu PIC16F877A bao gm c cc thanh ghi c chc nng c bit SFR nm cc cc nh a ch thp v cc thanh ghi mc ch dng chung GPR nm vng a ch cn li ca mi bank thanh ghi. Vng nh cc thanh ghi mc ch dng chung ny chnh l ni ngi dng s lu d liu trong qu trnh vit chng trnh. Tt c cc bin d liu nn c khai bo cha trong vng a ch ny. Trong cu trc b nh d liu ca PIC16F877A, cc thanh ghi SFR no m thng xuyn c s dng (nh thanh ghi STATUS) s c t tt c cc bank thun tin trong vic truy xut. S d nh vy l v, truy xut mt thanh ghi no trong b nh ca 16F877A ta cn phi khai bo ng bank cha thanh ghi , vic t cc thanh ghi s dng thng xuyn gip ta thun tin hn rt nhiu trong qu trnh truy xut, lm gim lnh chng trnh.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 25



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N :LCH VN NIN 26



Hnh 2.11 B nh d liu PIC 16F877A

SVTH: KHNH-LN-LIN

N :LCH VN NIN 27



Da trn s 4 bank b nh d liu PIC16F877A ta rt ra cc nhn xt nh sau : - Bank0 gm cc nh c a ch t 00h n 77h, trong cc thanh ghi dng chung cha d liu ca ngi dng a ch t 20h n 7Fh. Cc thanh ghi PORTA, PORTB, PORTC, PORTD, PORTE u cha bank0, do truy xut d liu cc thanh ghi ny ta phi chuyn n bank0. Ngoi ra mt vi cc thanh ghi thng dng khc ( s gii thiu sau) cng cha bank0 - Bank1 gm cc nh c a ch t 80h n FFh. Cc thanh ghi dng chung c a ch t A0h n Efh. Cc thanh ghi TRISA, TRISB, TRISC, TRISD, TRISE cng c cha bank1 - Tng t ta c th suy ra cc nhn xt cho bank2 v bank3 da trn s trn.Cng quan st trn s , ta nhn thy thanh ghi STATUS, FSR c mt trn c 4 bank. Mt iu quan trng cn nhc li trong vic truy xut d liu ca PIC16F877A l : phi khai bo ng bank cha thanh ghi . Nu thanh ghi no m 4 bank u cha th khng cn phi chuyn bank. Bng tm tt cc thanh ghi chc nng c bit:

SVTH: KHNH-LN-LIN

N :LCH VN NIN 28



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N :LCH VN NIN 29



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N :LCH VN NIN 30



Hnh 2.12-2.13-2.14 Cc thanh ghi chc nng t bit PIC 16F877A

SVTH: KHNH-LN-LIN

N :LCH VN NIN 31



2.1.2.6. Cc thanh ghi chc nng t bit: 2.1.2.6.1. Thanh ghi trng thi (Status Register): Thanh ghi ny c mt c 4 bank thanh ghi cc a ch 03h, 83h, 103h v 183h : cha kt qu thc hin php ton ca khi ALU, trng thi reset v cc bit chn bank cn truy xut trong b nh d liu.

Hnh 2.15 Status Register Bit 7 IRP: Bit la chn bank thanh ghi (S dng cho nh a ch gin tip). 1 = Bank 2, 3 (100h 1FFh ) 0 = Bank 0, 1 (00h FFh) Bit 6 5 RP1 RP0: Bit la chn bank thanh ghi (Dng trong nh i ch trc tip). 11 = Bank 3 ( 180h 1FFh) 10 = Bank 2 (100h 17Fh) 01 = Bank 1 (80h FFh) 00 = Bank 0 (00h 7Fh) Each bank is 128 bytes Bit 4 TO: Bit bo hiu hot ng ca WDT. 1: Lnh xa WDT hoc Sleep xy ra. 0: WDT hot ng. Bit 3 PD: Bit bo cng sut thp ( Power down bit). 1: Sau khi ngun tng hoc c lnh xa WDT. 0: Thc thi lnh Sleep. Bit 2 Z: bit Zero 1: Khi kt qu ca mt php ton bng 0.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 32



0: Khi kt qu ca mt php ton khc 0. Bit 1 DC: Digit Carry 1: C mt s nh c sinh ra bi php cng hoc php tr 4 bit thp. 0: Khng c s nh sinh ra. Bit 0 C: c nh (Carry Flag) 1: C mt s nh sinh ra bi php cng hoc php tr. 0: Khng c s nh sinh ra. 2.1.2.6.2. Thanh ghi ty chn (Option Reg Register): Thanh ghi ty chn cha cc bit iu khin cu hnh cho cc cha nng nh: ngt ngoi, Timer 0 chc nng ko ln Vdd ca cc chn Port B, v thi gian ch ca WDT.

Hnh 2.16 Option-Reg Register Bit 7 RBPU : Bit cho php PORTB c ko ln ngun. 1: Khng cho php PORTB ko ln ngun. 0: Cho php PORTB ko ln ngun. Bit 6 INTEDG: Bt la chn cnh tc ng ngt (INTERRUPT EDGE) 1: Ngt s c tc ng bi cnh ln ca chn RB0/INT 0: Ngt s c tc ng bi cnh xung ca chn RB0/INT Bit 5 T0CS: Bit la chn ngun xung Clock cho Timer 0 1: Xung Clock cung cp bi ngun ngoi qua chn RA4/T0CKI 0: Xung Clock cung cp bi ngun dao ng ni. Bit 4 T0SE: Bit la chn cnh no ca xung clock tc ng ln timer 0 1: Cnh xung 0: Cnh ln

SVTH: KHNH-LN-LIN

N :LCH VN NIN 33



Bit 3 PSA: Bit quyt nh tc m PS2:PS0 s tc ng ln Timer 0 hay WDT 1: Tc m PS2:PS0 s tc ng ln WDT 0: Tc m PS2:PS0 s tc ng ln Timer 0 Bit 2-0 PS2:PS0: Dng la chn tc m ca timer hay WDT

2.1.2.7 Khi qut chc nng cc Port trong vi iu khin PIC 16F877A: Cng xut nhp (I/O port) chnh l phng tin m vi iu khin dng tng tc vi th gii bn ngoi. S tng tc ny rt a dng v thng qua qu trnh tng tc , chc nng ca vi iu khin c th hin mt cch r rng. Mt cng xut nhp ca vi iu khin bao gm nhiu chn (I/O pin), ty theo cch b tr v chc nng ca vi iu khin m s lng cng xut nhp v s lng chn trong mi cng c th khc nhau. Bn cnh , do vi iu khin c tch hp sn bn trong cc c tnh giao tip ngoi vi nn bn cnh chc nng l cng xut nhp thng thng, mt s chn xut nhp cn c thm cc chc nng khc th hin s tc ng ca cc c tnh ngoi vi nu trn i vi th gii bn ngoi. Chc nng ca tng chn xut nhp trong mi cng hon ton c th c xc lp v iu khin c thng qua cc thanh ghi SFR lin quan n chn xut Vi iu khin PIC16F877A c 5 cng xut nhp, bao gm PORTA, PORTB, PORTC, PORTD v PORTE

2.1.2.7.1. Port A v thanh ghi TRIS A: SVTH: KHNH-LN-LIN N :LCH VN NIN 34



PORTA gm c 6 chn. Cc chn ca PortA, ta lp trnh c th thc hin c chc nng hai chiu : xut d liu t vi iu khin ra ngoi vi v nhp d liu t ngoi vi vo vi iu khin.

Hnh 2.17 Block diagram of RA3:RA0 Pins Port A gm 6 chn t RA0 n RA5. Vic ghi gi tr vo thanh ghi TRISA s qui nh cc chn ca Port A l input hay output(nu l 1 th l input, l output nu l 0). Vic c thanh ghi Port A s c trng thi ca cc chn Port A. Vic ghi gi tr vo thanh ghi Port A s thay i trng thi ca cc chn Port A. Ring chn RA4 c tch hp chc nng l chn cung cp xung clock ngoi cho Timer 0 (RA4/T0CKI). Nhng chn khc ca Port A c a hp vi cc chn ng vo Analog ca ADC v chn ng vo in th so snh ca b so snh Comparator. Hot ng ca nhng chn ny c quy nh bng nhng bit tng ng trong cc thanh ghi ADCCON1 v CMCON1.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 35



Hnh 2.18 Block Diagram of RA4/TOCKI Pin Khi cc chn ca Port A c s dng lm ng vo Analog th cc bit trong thanh ghi TRISA phi c set bng 1. Chc nng cc chn trong Port A.

Hnh 2.19 PORT A Function Ngoi ra, PORTA cn c cc chc nng quan trng sau : - Ng vo Analog ca b ADC : thc hin chc nng chuyn t Analog sang Digital - Ng vo in th so snh

SVTH: KHNH-LN-LIN

N :LCH VN NIN 36



- Ng vo xung Clock ca Timer0 trong kin trc phn cng : thc hin cc nhim v m xung thng qua Timer0 - Ng vo ca b giao tip MSSP (Master Synchronous Serial Port). Cc thanh ghi FSR lin quan n PORTA bao gm:

PORTA a ch 05h) : cha gi tr cc pin trong PORTA. TRISA (a ch 85h) : iu khin xut nhp. 2.1.2.7.2. PORT B v thanh ghi TRISB: PORTB c 8 chn t chn RB0-RB7. Vic ghi gi tr vo thanh ghi TRISB

s quy nh cc chn ca Port B l input hay output (1: input, 0: output). Vic c thanh ghi PortB s c trng thi ca cc chn Port B. Vic ghi gi tr vo thanh ghi Port B s thay i trng thi ca cc chn Port B. Ba chn ca Port B c a hp vi chc nng In-Circuit Debugger v Low Voltage Programming function: RB3/PGM, RB6/PGC, RB7/PGD. Mi chn Port B c mt transistor ko ln Vdd. Chc nng ny hot ng khi bit RBPU (Option ) c xa. Chc nng ny s t ng c xa khi Port B c quy nh l input. Bn chn ca Port B t RB7 n RB4 c chc nng ngt khi trng thi chn Port B thay i (Khi Port B c quy nh l output th chc nng ny khng hot ng. Gi trchn ca PortB c so snh vi gi tr c lu trc , khi c s sai lch gia 2 gi tr ny ngt s xy ra vi c ngt RBIF (INTCON=5V, in p ng ra Vout =5V. - Chn ni mass cng rt quan trng, nu chn ny b h th p ti ng ra s c th bng vi in p ng vo. iu ny s rt nguy him nu vi x l nhn c mc in p ny. - Khi 25 C, IC 7805 c c im nh sau: +in p a vo ti a: 35V +Nng lng tiu th : 20.8W +Nng lng tiu th khi khng c ming tn nhit : 20W +Nhit mi hn cho php : -30~150 C +Nhit cho php IC c th chu ng: -55~150 C

2.3. Chip DS1307: DS1307 l chip ng h thi gian thc ( RTC: Real-Time Clock ), khi nim thi gian thc y c dng vi ngha l thi gian tuyt i ca con ngi ang s dng, tnh bng giy, pht, giDS1307 l mt sn phm ca Dallas Semicondustor. Chip ny c 7 thanh ghi 8 bit cha thi gian l: giy, pht, gi, th ( trong tun ), ngy, thng, nm. Ngoi ra DS1307 cn c mt thanh ghi iu khin ng ra ph v 56 thanh ghi trng c th dng nh RAM. DS1307 c c v ghi thng qua giao din ni tip I2C ( TWI ca AVR ) nn cu to bn ngoi rt n gin . DS1307 xut hin 2 gi SOIC v DIP c 8 chn nh di hnh.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 54



Hnh 2.50. Hai gi cu to chip DS1307 Cc chn ca DS1307 c m t nh sau:

X1 v X2: l 2 ng kt ni vi mt thch anh 32.768KHz lm ngun to dao ng cho chip. VBAT: cc dng ca ngun pin 3V nui chip. GND: chn Mass chung cho c pin 3V v VCC. VCC: ngun cho giao din I2C, thng l 5V v dng chung vi vi iu khin. Nu VCC khng c cp ngun nhng VBAT c cp th DS1307 vn ang hot ng ( nhng khng ghi v c c ).

SQW/OUT: mt ng ph to xung vung ( Square Wave / Output Driver ), tn s ca xung c to c th c lp trnh. Nh vy chn ny hu nh khng lin quan n chc nng ca DS1307 l ng h thi gian thc, chng ta s b trng chn ny khi ni mch.

SCL v SDA: l 2 ng giao xung nhp v d liu ca giao din I2C C th kt ni DS1307 bng mt mch n gin sau:

SVTH: KHNH-LN-LIN

N :LCH VN NIN 55



Hnh 2.51. Mch ng dng dn gin ca DS1307. Cu to bn trong ca DS1307 bao gm mt s thnh phn nh: mch ngun, mch dao ng, mch iu khin logic, mch giao din I2C, con tr a ch v cc thanh ghi ( hay RAM ). Do a s cc thnh phn bn trong DS1307 l thnh phn cng nn chng ta khng c qu nhiu vic khi s dng DS1307. S dng DS1307 ch yu l ghi v c cc thanh ghi chip ny.

T chc b nh ca DS1307:

Hnh 2.52. T chc b nh ca DS1307 V 7 thanh ghi u tin l quan trng nht ca hot ng DS1307, chng ta s kho st cc thanh ghi chi tit hn. SVTH: KHNH-LN-LIN N :LCH VN NIN 56



Hnh 2.53. T chc cc thanh ghi thi gian Gi tr thi gian lu trong cc thanh ghi theo dng BCD. Thanh ghi giy ( Seconds ): l thanh ghi u tin trong b nh ca

DS1307, a ch ca n l 0x00. Bn bit thp ca thanh ghi ny cha m BCD 4 bit ca ch s hng n v ca gi tr giy. Do gi tr cao nht ca ch s hng chc l 5 nn ch cn 3 bit ( 6:4 ) l c th m ha c ( s 5=101, 3 bit ). Bit cao nht trong thanh ghi ny ( bit 7 ) l bit iu khin, nu bit ny bng 1 th chip v hiu ha, ng h khng hot ng.V vy phi set bit ny xung mc 0 ngay t u. Thanh ghi pht ( Minutes ): c a ch 0x01, cha gi tr pht ca

ng h. Tng t thanh ghi giy, bit 7 lun bng 0. Thanh ghi gi ( Hours ): thanh ghi c a ch 0x02. Trc ht 4 bit

thp ca thanh ghi ny c dng cho ch s hng n v ca gi. Do DS1307 h tr 2 loi h thng hin th gi ( gi l Mode ) l 12h ( 1h n 12h ) v 24h ( 1h n 24h ), bit 6 trong ( trong hnh 2.53 ) xc lp h thng gi.Nu bit 6 bng 0 th h thng 24h c chn, nu bit 6 bng 1 th h thng 12h c chn. Bit 5 ch bui trong ngy, AM hoc PM. Bit5=0 l AM, bit5=1 l PM, bit 7 lun bng 0.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 57



Thanh ghi th ( Day- ngy trong tun ): a ch 0x03. Thanh ghi Day mang gi tr t 1 n 7 tng ng t ch nht n th 7 trong 1 tun. V th ch c 3 bit thp trong thanh ghi ny c ngha.

Cc thanh ghi cn li c cu trc tng t, Date cha ngy trong thng ( 1 n 31 ), Month cha thng ( 1 n12 ), v Year cha nm ( 00 n 99 ). DS1307 ch dng cho 100 nm, nn gi tr nm ch c 2 ch s, phn u ca nm do ngi dng t thm vo ( v d 20xx ).

Ngoi cc thanh ghi trong b nh, DS1307 cn c cc thanh ghi khc nm ring gi l thanh ghi a ch ( Address Register ). Gi tr ca thanh ghi ny l a ch ca thanh ghi trong b nh m ngi dng mun truy cp. Thanh ghi a ch c t trong cu trc ca DS1307 ( hnh 2.54 ).

SVTH: KHNH-LN-LIN

N :LCH VN NIN 58



Hnh 2.54. Cu trc DS1307

SVTH: KHNH-LN-LIN

N :LCH VN NIN 59



2.4 Diode Diode l loi linh kin bn dn 2 cc c cu to da trn chuyn tip PN.in cc ni vi khi bn dn P gi l Anot, in cc ni vi khi bn dn N gi l Catot.Da vo cc t tnh ca chuyn tip P-N ngi ta ch to :diode chnh lu, diode tch sng,diode pht quang. 2.4.1 . Diode chnh lu: - Cu to: -K hiu:AP N

K

A(+)

K(-)

t tuyn Volt_Ampere: t tuyn Volt_Ampe l th biu din mi quan h gia dng in chy qua Diode v hiu in th gia hai u Diode.ID(mA)

VBR

0 0.7V(Si) VD(V) (

t tuyn Volt_Ampere ca Diode. -Phn loi: Diode nn in:c ch s bt u l 1N. Trn thn c vng mu trng l Catot. Diode tch sng c thn l thy tinh, trn thn diode c ch s bt u l 1N. Trn thn c vng mu en l Catot. ng dng ca Diode: chnh lu, tch sng

SVTH: KHNH-LN-LIN

N :LCH VN NIN 60

n tt nghip kha 2009-2011 2.4.2 Diode pht quang (Led n).


Mt s hnh nh v led n. - K hiu:D 7L E D

- p dng hiu ng in quang . Led ch pht sng khi c phn cc thun. Mi led pht mt bc x nht nh ty theo vt liu ch to v cht pha. GaAs bc sng Al,Sb GaAsP GaPZn GaAsS GaPN2 Dng trung bnh qua = 0,77-0,88 = 0,65

miliAmpere.

h phch = 0,57-0,58 vng = 0.55-0,56 lc led thng c chn l: 10 n 20

2.4.3 . Led 7 on : -Hnh dng :

SVTH: KHNH-LN-LIN

N :LCH VN NIN 61



Hnh 2.59. Hnh dng Led 7 on

- S chn :

Hnh 2.60. S chn Led 7 on

-Phn loi Led 7 on : Led 7 on c cu to t 7 led n. Led n l 1 diode khi c phn cc thun n s pht sng, cng dng hin th. Khi s dng mc ni tip vi in tr hn dng. Tnh ton in tr, chn Vled = 2V, Iled = 10mA. in tr hn dng c tnh theo cng thc R = (Vnguon Vled)/10mA. C 2 loi led 7 on :

Anode chung : chn Vcc c ni ln ngun thng qua in tr hn Cathode chung : chn Vcc c ni xung mass thng qua in tr

dng, cc chn cn li c ni vo chn IC gii m led 7 on. hn dng, cc chn cn li c ni vo chn IC gii m led 7 on.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 62



2.5 IN TR.

Bng gi tr cc vng mu trn in tr - K hiu: - Cch c vng mu: 1. in tr c 4 vng mu: -vng 1 v 2 l trng s. - vng 3 l bi s ca 10. - vng 4 l sai s. Vd: nu, den, , hong kim: 1000 + 5%. 2. in tr c 5 vng mu: - vng 1, 2 v 3 l trng s - vng 4 l bi s ca 10. - vng 5 l sai s. Vd: xanh dng, xm, , nu, bc: 6820 + 10% - Cch ghp in tr: 1. ghp ni tip:

SVTH: KHNH-LN-LIN

N :LCH VN NIN 63



2. ghp song song:

Rtd=1/R1+1/R2++1/Rn 3. ghp hn hp:

Rt=1/R1+1/R3+R2

2.6 T IN

Phn Loi T in V Cch c T in T in theo ng tn gi chnh l linh kin c chc nng tch t nng lng in, ni mt cch nm na. Chng thng c dng kt hp vi cc in tr trong cc mch nh thi bi kh nng tch t nng lng in trong mt khong thi gian nht nh. ng thi t in cng c s dng trong cc ngun in vi chc nng lm gim gn sng ca ngun trong cc ngun xoay chiu, hay trong cc mch lc bi chc nng ca t ni mt cch n gin l t ngn mch (cho dng in i qua) i vi dng in xoay chiu v h mch i vi dng in 1 chiu. Trong mt s cc mch in n gin, n gin ha trong qu trnh tnh ton hay thay th tng ng th chng ta thng thay th mt t in bng mt dy dn khi c dng xoay chiu i qua hay tho t ra khi mch khi c dng mt chiu trong mch. iu ny kh l cn thit khi thc hin tnh ton hay xc nh cc s mch tng ng cho cc mch in t thng thng.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 64



Hin nay, trn th gii c rt nhiu loi t in khc nhau nhng v c bn, chng ta c th chia t in thnh hai loi: T c phn cc (c cc xc nh) v t in khng phn cc (khng xc nh cc dng m c th). c trng cho kh nng tch tr nng lng in ca t in, ngi ta a ra khi nim l in dung ca t in. in dung cng cao th kh nng tch tr nng lng ca t in cng ln v ngc li. Gi tr in dung c o bng n v Fara (k hiu l F). Gi tr F l rt ln nn thng thng trong cc mch in t, cc gi tr t ch o bng cc gi tr nh hn nh micro fara (F), nano Fara (nF) hay picro Fara (pF). 1F = 106F = 109nF = 1012pF

- T Ho

K hiu t ho v hnh dng t ho T ha l mt loi t c phn cc. Chnh v th khi s dng t ha yu cu ngi s dng phi cm ng chn ca t in vi in p cung cp. Thng thng, cc loi t ha thng c k hiu chn c th cho ngi s dng bng cc k hiu + hoc = tng ng vi chn t. C hai dng t ha thng thng l t ha c chn ti hai u tr trn ca t (t c ghi 220F trn hnh a) v loi t ha c 2 chn ni ra cng 1 u tr trn (t c ghi gi tr 10F trn hnh a). ng thi trn cc t ha, ngi ta thng ghi km gi tr in p cc i m t c th chu c. Nu trng hp in p ln hn so vi gi tr in p trn t th t s b phng hoc n t ty thuc vo gi tr in p cung cp. Thng thng, khi chn cc loi t ha ny ngi ta thng chn cc loi t c gi tr in p ln hn cc gi tr in p i qua t m bo t hot ng tt v m bo tui th ca t ha. - T khng phn cc :

SVTH: KHNH-LN-LIN

N :LCH VN NIN 65



T thng Cc loi t nh thng khng phn cc. Cc loi t ny thng chu c cc in p cao m thng thng l khong 50V hay 250V. Cc loi t khng phn cc ny c rt nhiu loi v c rt nhiu cc h thng chun c gi tr khc nhau. Rt nhiu cc loi t c gi tr nh c ghi thng ra ngoi m khng cn c h s nhn no, nhng cng c cc loi t c thm cc gi tr cho h s nhn. V d c cc t ghi 0.1 c ngha gi tr ca n l 0,1F=100nF hay c cc t ghi l 4n7 th c ngha gi tr ca t chnh l 4,7nF - Cc loi t c dng m:

T thng M s thng c dng cho cc loi t c gi tr nh trong cc gi tr c nh ngha ln lt nh sau: - Gi tr th 1 l s hng chc - Gi tr th 2 l s hng n v - Gi tr th 3 l s s khng ni tip theo gi tr ca s to t gi tr 1 v 2. Gi tr ca t c c theo chun l gi tr picro Fara (pF) - Ch s i km sau cng l ch gi tr sai s ca t. V d: T ghi gi tr 102 th c ngha l 10 v thm 2 s 0 ng sau = 1000pF = 1nF ch khng phi 102pF

SVTH: KHNH-LN-LIN

N :LCH VN NIN 66



Hoc v d t 272J th c ngha l 2700pF=2,7nF v sai s l 5% Chng thng c ch nh vi cc gi tr t in ti thiu, khong t 2 ti 10 pF. 2.7 Transistor. - Cu to ca transistor: Transistor l t ghp ca hai t Transfer v t Resistor c dch l in chuyn ( nhng khng thng dng ) . Transistor l linh kin bn dn gm ba lp bn dn tip gip nhau to thnh hai mi ni P-N . Ty theo cch sp xp th t cc vng bn dn ngi ta ch to ra hai loi transistor l transistor PNP v NPN . Cc pht E ( Emitter ) Cc nn B ( Base ) Cc thu C ( Collector )

N

P

N

P

N

P

Cu to transistor Ba vng bn dn c ni ra ba chn v gi l cc pht E , cc nn B v cc thu C .Cc pht E v cc thu C tuy cng tnh cht bn dn nhng do kch thc v nng pha tp cht khc nhau nn khng th han i cho nhau c phn bit vi cc lai transistor khc , lai transistor PNP v NPN cn gi l transistor lng ni BJT ( Bipolar Junuction Transistor ). - K hiu: a. K hiu :Loi N-P-NC 2 B 1 3 N E P N

Loai P-N-PC P E N P

B

SVTH: KHNH-LN-LIN

N :LCH VN NIN 67



b. Hnh dng: Hnh dng cc loi transistor thng dng

- c tuyn ca transistor: a.c tuyn ng vo : c tuyn IB/VBE c dng ging nh c tuyn ca diode , sau khi in th phn cc VBE tng n gi tr in th thm V th bt u c dng in IB v dng in IB cng tng theo hm s m nh dng in IB ca diode . mi in th VBE th dng in IB c gi tr khc nhau nh sau : VBE = 0.45 v VBE = 0.5 v VBE = 0.55 v VBE = 0.6 v IB = 10 A IB = 20 A IB = 30 A IB = 40 A

IC

RB IB VBE

RC VCE

c tuyn trn c v ng vi in th VCE = 2 v , khi in th VCE > 2 v th c tuyn thay i khng ng k .

SVTH: KHNH-LN-LIN

N :LCH VN NIN 68

n tt nghip kha 2009-2011 b.c tuyn truyn dn : tuyn

GVHD: Thy Nguyn Hu PhcIC IC c tuyn VCE VCE

c dng ging nh c

IC nh dng in I C c gi tr khc nhau v d nh sau : V BE

VCE VCE VCE VCE

0.45 v IC 1 mA 0.5 v IC 2 mA 0.55 v IC 3 mA 0.6 v IC 4 mAIC = gi l khuch i dng in ca transistor. IB

Ngi ta to t s

c tuyn ng ra :

IC VCE

SVTH: KHNH-LN-LIN

N :LCH VN NIN 69



- Cc thng s k thut ca transistor : c tnh k thut ca transistor ngoi ba c tnh quan trng va xt trn cn c mt s thng s k thut c ngha gii hn m cn phi bit khi s dng transisor. a ) khuch i dng in : khuch i dng in ca transistor tht ra khng phi l mt hng s m c gi tr thay di theo dng in IC . b ) in th gii hn : in th nh thng BV ( Breakdown Voltage ) l in th ngc ti a t vo cc cp cc , nu qu in th ny th transistor s b h . C ba loi in th gii hn : VCEO in th nh thng gia cc C v cc E khi cc B h VCBO in th nh thng gia cc C v cc B khi cc E h VEBO in th nh thng gia cc E v cc B khi cc C h c ) Dng in gii hn : Dng in qua transistor phi c gii hn mt mc cho php nu qu tr s ny th transistor s b h . Ta c : ICmax l dng in ti a cc C IBmax l dng in ti a cc B d ) Cng sut gii hn : Khi c dng in qua transistror s sinh ra mt cng sut nhit lm nng transistor, cng sut sinh ra c tnh theo cng thc : PT = IC . VCE Mi transistor c mt cng sut gii hn c gi l cng sut ti a PDmax ( Dissolution ) .Nu cng sut sinh ra trn transistor ln hn cng sut PDmax th tansistor s b h . d ) Tn s ct : ( thit on ) Tn s thit on ( fcut-cut ) l tn s m transistor ht kh nng khuch i , lc in th ng ra bng in th ng vo .-

- Xt Transistor PNP . Trong phn 2 ni v nguyn l ca transistor ,ta bit transisor PNP phn cc vi cc in th ngc du vi transistor NPN, ng thi cc transistor lai NPN thng thng lm bng cht Si trong khi transistor PNP thng thng lm bng cht Ge . Mch in hnh 2.8 l mch th nghim c tnh k thut ca Transistor PNP vi cc ngun in th phn cc m cho cc B v cc C . Transistor PNP cng c c tuyn ng vo , c tuyn truyn dn , c tuyn ng ra v cc thng s k thut tng t nh transistor NPN nh gi tr in th v dng in u c tr s m.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 70



- PHN CC TRANSISTOR : a.i cng : Transistor c rt nhiu ng dng trong cc thit b in t ty theo tng ng dng c th m transistor cn phi cung cp n th v dng in cho tng chn mt cch thch hp .Vic chn in th v in tr cc chn transistor gi l phn cc cho transistor. b.Phn cc bng hai ngun in ring : * Trng hp khng c RE :

RC VBB

3 K

RB 1

2 0 K

3 V

VB

1 2 V E

VC

C

S mch Xt mch in hnh 2.9 l mch phn cc cho transistor c khuch i dng in = 100 v VBE =0.6 v . Nu IC = 0 th VCC = VCECC Nu VCE = 0 v th I C = R = ICmax C

V

ng thng ni hai im VCC = VCE v ICmax = ti tnh v cng thc : I C =

VCC RC

gi l ng

VCC VCE gi l phng trnh ng ti tnh . im RC

lm vic ca transistor l im c ta Q nm trn ng ti tnh .Khi thay i dng in IB s lm thay i dng in IC v im lm vic ca transistor s thay i v tr trn ng ti tnh.

SVTH: KHNH-LN-LIN

N :LCH VN NIN 71



* Trng hp c RE : Trng hp mch in hnh 2.11 c thm in tr RE cc E

2 . 5 K

RB RB 7 VBB 0 K

VC

E

VC1 2 V

C

IB RE0 . 5 K

3 V

S mch Phng trnh ng ti tnh l :IC = VCC VCE RC + R E

Nu IC = 0 th VCC = VCECC Nu VCE = 0 th I C = R + R = ICmax C E

V

Ni lin hai im VCE = VCC v I C max =

VCC ta c ung ti tnh RC + R E

SVTH: KHNH-LN-LIN

N :LCH VN NIN 72



c.Phn cc bng mt ngun in chung : Phn cc cho cc B bng in tr RB : Trong mch in hnh 2.13 cc B dng ngun VCC Phng trnh ng ti tnh l :IC = VCC VCE RC + R E

2 . 5 K

RC RB 5 IB2 0 k

Trong mch in hnh 2.11 c in tr RE v RC ging nh in tr trong mch in hnh 2.13 nn mch ny cng c ng ti tnh v im lm vic ging nh hnh trn Phn cc cho cc B bng cu phn th :

VB

VCE 1 2 V

C

RE0 . 5 K

Trong mch in hnh 2.13 cc B c phn cc bng ngun V CC gim th qua cu phn th RB1 v RB2 . ng vo c hai dng in l I B t ngun VCC i qua hai in tr RB1 v RB2 xung mass v dng in IB t ngun qua in tr RB1 vo trong transistor .Vic tnh tan dng in v in th cc chn transistor s phc tp hn cc mch trn .

RB5 6 K

IC1 2 . 5 K

IC2 . 5 K

RC IB

RC IBVC1 2 V C

RB VBB

VC1 2 V

C

RB5 6 K

2

IE

RE0 . 5 K

IE

RE0 . 5 K

- nh hng ca nhit i vi cc thng s ca transistor: SVTH: KHNH-LN-LIN N :LCH VN NIN 73



Hu ht cc thng s k thut ca transistor u b thay i theo nhit ,trong c ba thng s chu nh hng nht l dng n r I CBO, khuch i , in th phn cc VBE nh hng i vi ICBO : Dng in r ICBO l dng c ht ti thiu s , khi nhit tng th dng I CBO s tng theo hm s m , thng i vi Transistor Ge , nhit tng 120 C th dng in ICBO tng gp i , i vi Transitor Si , nhit tng 80C th dng ICBO tng gp i . Tuy tng dng r ICBO ca Si li rt nh so vi dng r Ge . Do , i vi transistor Ge yu t nhit nh hng ln dng r quan trng hn lai transistor Si . nh hng i vi khuch i : Nh bit khuch i thay i theo dng in IC .Khi nhit tng lm IC tng v cng tng theo . nh hng i vi phn cc VBE : in th phn cc VBE khang 0.5 n 0.7 v cho transitor Si v khang 0.1- 0.3v cho transistor Ge . Khi nhit tng V BE s b gim .Thng thng , khi nhit tng 10C th VBE gim xung 2.4 mV . Trong ba thng s trn dng in r IBCO nh hng quan trng nht VI.8 Cc bin php n nh nhit : trnh nh hng ca nhit ln cc thng sca transistor c th lm sai im lm vic tnh Q ngi ta dng cc bin php phn cc cc transistor nh sau : Dng in tr RE n nh nhit : Khi nhit tng th dng in Ic tng ln .Khi IE tng s lm VE tng ( VE= IE. RE) trong khi in th phn cc VB gn nh khng thay i nh cu phn th . Lc in th VBE s gim xung ( VBE = VB VE ) lm cho dng IB gim theo c tuyn ng vo IB/VBE . Dng in IB s ko IC gim xung v nhit transistor c n nh . Dng in tr hi tip t cc C : Theo mch in hnh 2.16a in th phn cc VB c ly t cc C gim th qua in tr RB . Trong mch ny dng in ng vo IB c tnh theo cng thc :IB = R B + .R E VC V BE

Khi nhit tng lm IC tng v VC b gim ( v VC = VCC IC. RC ) theo cng thc trn khi VC gim s lm cho IB gim xung v ko IC gam xung nhit transistor c n nh .Trong mch ny in tr RE vn c tc dng n nh nhit theo nguyn l mch in hnh 2.16a .

SVTH: KHNH-LN-LIN

N :LCH VN NIN 74



Dng cu phn th c in tr nhit Th ghp song song in tr RB2 l lai in tr co h s nhit m . in tr ny c t vo v ca transistor nn khi nhit ca transistor tng ln th in tr nhit li nng v lm gim tr s in tr lm gim thp in th phn cc VE. Lc dng in IB gim ko IC gim xung theo Mch in di ch dng cho cc transistor khuch i cng sut ln .

- BA CCH GHP CN BN : a .Ba cch mc cn bn : Mch khuch i hnh 2.17 c tn hiu vo cc B v ly ra cc C , cc E c t phn dng CE xung mass nn cc E khng c tn hiu xoay chiu c gi l cc chung. Mch ny gi l mch khuch i ghp kiu E chung .tng t transistor cn c th ghp kiu B chung hay l C chung . a.1)Mch khuch i kiu E chung :( CE : commonemitter ) Cc thng s k thut ca mch : Vc Tng tr ng vo :v v ri = i = be ii ib

c

V0 iC Vi ib RE RC

Tng tr ng ra :v v r0 = 0 = cc i0 ic

khuch i dng in :AI = i0 ic = = i0 ib

khuh i in th :Av = v 0 v ce Rc = = v i vbe ri

SVTH: KHNH-LN-LIN

N :LCH VN NIN 75



a.2)Mch khuh i kiu b chung : ( CB : common base ) Trong mch transistor ghp kiu B chung C t in phn dng CB ni mass nn cc B Khng c tn hiu xoay chiu .Tn hiu a vo cc E ly ra cc C. Cc thng s ca mch l Vc c Tng tr ng vo :ri = v 0 vb = ii ibv 0 v be = i0 ie

RB

1

RC

V0

Tng tr ng ra :r0 =

Vi CB RB2

RE

a.3 ) Mch khuch i kiu C chung : ( CC : common collector ) Trong mch khuch i kiu C chung th cc C c ni thng ln ngun VCC ( c gi l mass xoay chiu ) nn cc C khng c tn hiu .Tn hiu vo cc B v ly ra cc E . Cc thng s ca mch : Tng tr ng vo :ri = vi vb = ii ib v 0 Vbe = i0 ie

Vc iC Vi RC

c

V0

Tng tr ng ra :r0 =

khuch i dng in :Al = i0 ie = = + 1 ii ib

khuch i in th :

SVTH: KHNH-LN-LIN

N :LCH VN NIN 76

n tt nghip kha 2009-2011Av = v0 ve = vi vb


b .Bng so snh cc thng s ca transistor theo ba cch ghp : Nhn xt : Transistor ghp kiu E chung c khuch i mnh nht v AI v AV u ln . Transistor ghp kiu B chung c ri rt nh v r0 rt ln nn dng i tng tr t nh ra ln . Transistor ghp kiu C chung c ri rt ln v r0 rt nh nn dng i tng tr t ln ra nh . Cch ghp Tng tr vo ri Tng tr ra r0 khuch i in th Av khuch i dng in AI Pha gia cc tn hiu vo v ra E chung hie = rb re Vi kilo-ohm Vi chc kilo ohm B chung Vi kiloohm Vi trm kilo-ohm Vi trm ln 1 C chung hie + RE Vi kiloohm Re + (rb + rs)/ Vi chc -ohm 1 +1 vi chc vi trm ohm ) ng pha

- ( vi trm ln ) hie = (vi chc vi trm ohm ) o pha

ng pha

c. Ba trng thi ca transitor : Mch tng ng ca transistor nh hnh v di y . Xt l trng hp transistor trng thi khuch i tuyn tnh .Tht ra ty theo mc phn cc m transistor c th lm vic mt trong ba trng thi l : ngng dn , khuc i tuyn tnh v bo ha .

SVTH: KHNH-LN-LIN

N :LCH VN NIN 77



VC RC RB VBB

C

VB

VCE

E

Trng thi ngng dn : Nu phn cc cho transistor c VBE>4; dv_p=p&15; c_h=(h&240)>>4; dv_h=h&15; thu = th; c_d=(d&240)>>4; dv_d=d&15; c_t=(t&240)>>4; dv_t=t&15; c_n=(n&240)>>4; dv_n=n&15; } void convert_so_lcd(int8 x) SVTH: KHNH-LN-LIN N :LCH VN NIN 90

n tt nghip kha 2009-2011 { low=x%10; high=x/10; low = low + 0x30; high = high + 0x30; } void chinh_gio() { int mode=1,i=0,t; ReadRTC(&RTC_ARR[0]);


convert_bcd_lcd(RTC_ARR[0],RTC_ARR[1],RTC_ARR[2],RTC_AR R[3],RTC_ARR[4],RTC_ARR[5],RTC_ARR[6]); h = c_h*10+dv_h; p = c_p*10+dv_p; g = c_g*10+dv_g; while(1) { if(i40) i = 0; if(k2==0) { while(k2==0) {} switch(mode) { case 1: { if(h0) g--; else g = 59; break;} } }


if(k1==0) { while(k1==0){} mode++; if(mode>3) break;} if(k4==0) { while(k4==0){} break;} } //----------------------------------// luu lai thoi gian chinh //----------------------------------//ReadRTC(&RTC_ARR[0]); c_g = g/10; dv_g = g%10; c_p = p/10; dv_p = p%10; c_h = h/10; dv_h = h %10; SVTH: KHNH-LN-LIN N :LCH VN NIN 92

n tt nghip kha 2009-2011 RTC_ARR[0] = (c_g

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