Xa iinjineli ze-elektroniki zisenza uyilo olubuyela umva okanye umsebenzi wokulungisa izixhobo zombane, kufuneka kuqala ziqonde unxibelelwano phakathi kwamacandelo kwizinto ezingaziwayo. ibhodi yesekethe eprintiweyo (PCB), ngoko unxulumano lonxibelelwano phakathi kwezikhonkwane zecandelo kwi-PCB kufuneka lulinganiswe kwaye lurekhodwe.

Eyona ndlela ilula kakhulu kukutshintsha i-multimeter kwifayile “ye-short-circuit buzzer”, sebenzisa iimvavanyo ezimbini ezikhokelela ukulinganisa uxhulumaniso phakathi kwezikhonkwane nganye nganye, kwaye emva koko urekhode ngesandla isimo sokuvula / sokuvala phakathi kwe “pin pairs”. Ukuze ufumane isethi epheleleyo yobudlelwane bonxibelelwano phakathi kwazo zonke “iipeyibhile zepini”, “izibini zepini” ezivavanyiweyo kufuneka zilungelelaniswe ngokomgaqo wokudibanisa. Xa inani lamacandelo kunye nezikhonkwane kwi-PCB likhulu, inani le “pin pairs” ezifuna ukulinganiswa ziya kuba zikhulu. Ngokucacileyo, ukuba iindlela zezandla zisetyenziselwa lo msebenzi, umthwalo wokulinganisa, ukurekhoda kunye nokuhlolwa kwakhona kuya kuba mkhulu kakhulu. Ngaphezu koko, ukuchaneka komlinganiselo kuphantsi. Njengoko sonke siyazi, xa i-impedance resistive phakathi kweepeni ezimbini zeemitha ze-multimeter ngokubanzi ziphezulu malunga ne-20 ohms, i-buzzer iya kuvakala, eboniswa njengendlela.

Ukuze kuphuculwe ukusebenza kakuhle kokulinganisa, kuyimfuneko ukuzama ukuqonda umlinganiselo ozenzekelayo, ukurekhoda kunye nokulinganisa kwecandelo “i-pin pair”. Ukuza kuthi ga ngoku, umbhali wayila i-detector yendlela elawulwa yi-microcontroller njengesixhobo sokubona isiphelo sangaphambili, kwaye yenzelwe isoftware yokulinganisa umlinganiselo onamandla wokusetyenzwa ngasemva ukuze kuhlangatyezwane ukulinganisa okuzenzekelayo kunye nokurekhodwa kobudlelwane bendlela phakathi kwezikhonkwane zecandelo. kwiPCB. . Eli nqaku lixubusha kakhulu ngeengcamango zoyilo kunye neteknoloji yokulinganisa ngokuzenzekelayo ngesekethe yokufumanisa indlela.

Imfuneko yokulinganisa ngokuzenzekelayo kukudibanisa izikhonkwane zecandelo phantsi kovavanyo kwisekethe yokufumanisa. Kule nto, isixhobo sokufumanisa sixhotyiswe ngeentloko ezininzi zokulinganisa, ezikhokelwa ngaphandle ngeentambo. Iintloko zokulinganisa zinokudityaniswa kwizixhobo ezahlukeneyo zovavanyo ukuseka unxibelelwano kunye nezikhonkwane zecandelo. Intloko yokulinganisa Inani lezikhonkwane linquma inani lezikhonkwane ezixhunyiwe kwisekethe yokufumanisa kwibhetshi enye. Emva koko, phantsi kolawulo lweprogram, i-detector iya kufaka i-“pin pairs” evavanyiweyo kwindlela yokulinganisa enye nganye ngokomgaqo wokudibanisa. Kwindlela yokulinganisa, imo yokuvula/yokuvala phakathi “kwezibini zepini” iboniswa njengokuba kukho ukuchasana phakathi kwezikhonkwane, kwaye indlela yokulinganisa iyiguqulela kumbane, ngaloo ndlela igweba unxibelelwano lokuvula/lokuvala phakathi kwabo kunye nokurekhoda.

Ukwenzela ukuba isekethe yokubona ikwazi ukukhetha izikhonkwane ezahlukeneyo ngokulandelelana ukusuka kwiintloko ezininzi zokulinganisa eziqhagamshelwe kwizikhonkwane zecandelo lokulinganisa ngokomgaqo wokudibanisa, uluhlu oluhambelanayo lokutshintsha lunokusetwa, kwaye iiswitshi ezahlukeneyo zinokuvulwa / zivaliwe. inkqubo ukuswitsha icandelo izikhonkwane. Ngenisa indlela yokulinganisa ukufumana ubudlelwane bokuvula/ukuvala. Ekubeni umlinganiselo womthamo we-analog voltage, i-analog multiplexer kufuneka isetyenziswe ukwenza uluhlu lokutshintsha. Umzobo 1 ubonisa ingcamango yokusebenzisa i-analog switch array ukutshintshela ipini evavanyiweyo.

Umgaqo woyilo wesekethe yokufumanisa uboniswe kuMfanekiso 2. Iisethi ezimbini zokutshintsha kwe-analog kwiibhokisi ezimbini ze-I kunye ne-II kumzobo ziqulunqwe ngamabini: I-1 kunye ne-II-1, I-2 kunye ne-II-2. . … ., Ⅰ-N kunye Ⅱ-N. Ingaba iinguqu ezininzi ze-analog zivaliwe okanye azilawulwa yiprogram ngokusebenzisa isiphaluka se-decoding eboniswe kuMzobo 1. Kwiinguqu ezimbini ze-analog I kunye ne-II, iswitshi enye kuphela inokuvalwa ngexesha elifanayo. Ngokomzekelo, ukufumanisa ukuba kukho ubudlelwane bendlela phakathi kwentloko yokulinganisa i-1 kunye nentloko yokulinganisa i-2, vala iitshintshi I-1 kunye ne-II-2, kwaye wenze indlela yokulinganisa phakathi kwendawo A kunye nomhlaba ngokusebenzisa iintloko zokulinganisa 1 kunye ne-2. Ukuba kunjalo yindlela, Emva koko amandla ombane kwindawo A VA=0; ukuba ivuliwe, ngoko VA>0. Ixabiso le-VA lisisiseko sokugweba ukuba kukho ubudlelwane bomendo phakathi kweentloko zokulinganisa i-1 kunye ne-2. Ngale ndlela, ubudlelwane bokuvula / ukuvala phakathi kwazo zonke izikhonkwane ezixhunywe kwintloko yokulinganisa zingalinganiswa ngokukhawuleza ngokutsho indibaniselwano umgaqo. Ekubeni le nkqubo yokulinganisa iqhutyelwa phakathi kwezikhonkwane zecandelo eligxininiswe yi-test fixture, umbhali uyibiza ngokuba yi-in-clamp measurement.

Ukuba iphini yecandelo alinakunyanzeliswa, kufuneka lilinganiswe ngesikhokelo sovavanyo. Njengoko kuboniswe kwi-Figure 2, qhagamshela uvavanyo olunye olukhokelela kumzila we-analog kunye nomnye emhlabeni. Ngeli xesha, umlinganiselo unokwenziwa ngokude nje ukuba i-control switch I-1 ivaliwe, ebizwa ngokuba yi-pen-pen measurement. Isekethe eboniswe kuMzobo 2 ingasetyenziselwa ukugqiba umlinganiselo phakathi kwazo zonke izikhonkwane ezibambekayo zentloko yokulinganisa kunye nezikhonkwane ezingenakunqandwa zichukunyiswe yipeni yemitha yokumisa ngephanyazo. Ngeli xesha, kuyimfuneko ukulawula ukuvalwa kokutshintsha kweNombolo ye-No. Le nkqubo yokulinganisa inokubizwa ngokuba ngumlinganiselo wepen clamp. I-voltage elinganisiweyo, ngokwethiyori, kufuneka ibe yisekethe xa i-VA = 0, kwaye kufuneka ibe yisekethe evulekileyo xa i-VA> 0, kwaye ixabiso le-VA lihluka ngexabiso lokumelana phakathi kweendlela ezimbini zokulinganisa. Nangona kunjalo, ekubeni i-analog multiplexer ngokwayo ine-non-non-resistance RON, ngale ndlela, emva kokuba indlela yokulinganisa yenziwe, ukuba yindlela, i-VA ayilingani no-0, kodwa ilingana nokuhla kwamandla ombane kwi-RON. Ekubeni injongo yokulinganisa kukwazi kuphela unxibelelwano lwe-on / off, akukho mfuneko yokulinganisa ixabiso elithile le-VA. Ngenxa yesi sizathu, kuyimfuneko kuphela ukusebenzisa i-comparator ye-voltage ukuthelekisa ukuba i-VA inkulu kunokwehla kombane kwi-RON. Misela i-voltage ye-threshold ye-voltage comparator ukuze ilingane nokuhla kwamandla ombane kwi-RON. Imveliso ye-voltage comparator yisiphumo sokulinganisa, okuyinani ledijithali elinokufundwa ngokuthe ngqo yi-microcontroller.

Ukumiselwa kombane wethreshold

Iimvavanyo zifumene ukuba i-RON inomahluko ngamnye kwaye inxulumene nobushushu be-ambient. Ngoko ke, i-voltage ye-threshold kufuneka ilayishwe kufuneka ibekwe ngokwahlukileyo kunye neshaneli yokutshintsha i-analog evaliweyo. Oku kunokufezekiswa ngokucwangcisa iD/A isiguquli.

Isiphaluka esiboniswe kwi-Figure 2 singasetyenziselwa ukucacisa ngokulula idatha ye-threshold, indlela yokuvula i-switch pairs I-1, II-1; I-2, II-2; …; IN, II-N; ifomu I-loop ye-Path, emva kokuba isibini ngasinye sokutshintsha sivaliwe, thumela inombolo kwi-converter ye-D / A, kwaye inombolo ethunyelweyo iyanda ukusuka kwincinci ukuya enkulu, kwaye ilinganise imveliso ye-voltage comparator ngeli xesha. Xa imveliso ye-voltage comparator itshintsha ukusuka kwi-1 ukuya kwi-0, Idatha ngeli xesha ihambelana ne-VA. Ngale ndlela, i-VA yeshaneli nganye inokulinganiswa, oko kukuthi, i-voltage drop on RON xa i-pair of switches ivaliwe. Kwi-multiplexers ye-analog echanekileyo ephezulu, umahluko ngamnye kwi-RON uncinci, ngoko ke isiqingatha se-VA esilinganiswa ngokuzenzekelayo yinkqubo sinokuqikelelwa njengedatha ehambelanayo yokuhla kwamandla ombane kwi-RON echaphazelekayo yokutshintsha. Idatha ye-Threshold yokutshintsha kwe-analog.

Ukusetwa okuguquguqukayo kombane wethreshold

Sebenzisa i-threshold data elinganiswe ngasentla ukwakha itafile. Xa ulinganisa kwi-clamp, khupha idatha ehambelanayo kwitheyibhile ngokweenombolo zeetshintshi ezimbini ezivaliweyo, kwaye uthumele isamba sabo kwi-converter ye-D / A ukwenza i-voltage threshold. Ngomlinganiselo wekliphu yepeni kunye nomlinganiselo wepen-pen, kuba indlela yokulinganisa idlula kuphela kwi-analog switch ye-No.

Ukongeza, ngenxa yokuba isekethe ngokwayo (i-D/A converter, i-voltage comparator, njl.njl.) ineempazamo, kwaye kukho ukunganyangeki koqhagamshelwano phakathi kwesixhobo sovavanyo kunye nepini evavanyiweyo ngexesha lomlinganiso wokwenyani, olona mbane wombane usetyenziswayo kufuneka ube ngaphakathi komda. kumiselwe ngokwendlela engentla. Yongeza isixa sokulungiswa kwisiseko, ukuze ungajongi kakubi indlela njengesiphaluka esivulekileyo. Kodwa i-voltage eyandisiweyo yombane iya kukongamela ukuxhathisa okuncinci, oko kukuthi, ukuchasana okuncinci phakathi kwezikhonkwane ezimbini kugwetywa njengendlela, ngoko ke isixa sokulungiswa kombane kufuneka sikhethwe ngokufanelekileyo ngokwemeko yokwenyani. Ngokusebenzisa iimvavanyo, isiphaluka sokufumanisa sinokuchaneka ngokuchanekileyo ukuchasana phakathi kwezikhonkwane ezimbini ezinexabiso lokumelana nexabiso elikhulu kune-5 ohms, kwaye ukuchaneka kwayo kuphezulu kakhulu kune-multimeter.

Ziliqela iimeko ezizodwa zeziphumo zomlinganiselo

Impembelelo yesakhono

Xa i-capacitor ixhunywe phakathi kwezikhonkwane ezivavanyiweyo, kufuneka zibe kubudlelwane obuvulekileyo besiphaluka, kodwa indlela yokulinganisa ihlawulisa i-capacitor xa i-switch ivaliwe, kwaye amanqaku amabini okulinganisa afana nendlela. Ngeli xesha, umphumo wokulinganisa ofundwe kwi-comarator ye-voltage yindlela. Ngolu hlobo lwendlela yobuxoki ebangelwa yi-capacitance, ezi ndlela zimbini zilandelayo zingasetyenziselwa ukusombulula: ngokufanelekileyo ukwandisa umlinganiselo wangoku ukunciphisa ixesha lokuhlawula, ukwenzela ukuba inkqubo yokuhlawula iphele ngaphambi kokufunda iziphumo zokulinganisa; yongeza uhlolo lweendlela eziyinyani kunye nobuxoki kwisoftware yokulinganisa Icandelo lenkqubo (jonga icandelo 5).

Impembelelo ye-inductance

Ukuba i-inductor ixhunyiwe phakathi kwezikhonkwane ezivavanyiweyo, kufuneka zibe kubudlelwane obuvulekileyo besiphaluka, kodwa ekubeni ukuchasana kwe-static kwe-inductor kuncinci kakhulu, umphumo ulinganiswe nge-multimeter uhlala uyindlela. Ngokuchasene nemeko yokulinganisa i-capacitance, okwangoku xa i-analog switch ivaliwe, kukho i-electromotive force eyenziwe ngenxa ye-inductance. Ngale ndlela, i-inductance inokugwetywa ngokuchanekileyo ngokusebenzisa iimpawu zesantya sokufumana ngokukhawuleza kwesiphaluka sokufumanisa. Kodwa oku kuyangqubana nemfuneko yomlinganiselo wecapacitance.

Impembelelo ye-analog switch jitter

Kumlinganiselo wangempela, kufunyenwe ukuba ukutshintshwa kwe-analog kunenkqubo ezinzileyo ukusuka kwimeko evulekileyo ukuya kwindawo evaliweyo, ebonakaliswa njengokuguquguquka kwe-voltage VA, eyenza iziphumo zokulinganisa ezimbalwa zokuqala zingahambelani. Ngenxa yesi sizathu, kuyimfuneko ukugweba iziphumo zendlela ngamaxesha amaninzi kwaye ulinde ukuba iziphumo zokulinganisa zihambelane. Qinisekisa kamva.

Ukuqinisekiswa kunye nokurekhodwa kweziphumo zomlinganiselo

Ukuqwalasela ezi ngasentla iimeko ezahlukeneyo, ukuze ulungelelanise izinto ezahlukeneyo ezivavanyiweyo, iprogram yeprogram ye-block diagram eboniswe kuMzobo 3 isetyenziselwa ukuqinisekisa nokurekhoda iziphumo zokulinganisa.