A yau mun kwatanta wani sabon bangaren da aka saka cikin jerin mu, Schmitt Trigger, wanda mutane da yawa ba su sani ba waɗanda yanzu za su daina zama abin asiri. Kuma za mu bayyana duk abin da kuke buƙatar sani game da shi, kamar abin da yake, menene, yadda wannan na'urar lantarki ke aiki, har ma za ku iya haɗa shi da ayyukanku tare da Arduino, Da dai sauransu
Don haka, bari mu ga abin da wannan kashi zai iya yi mana...
Abubuwan da suka dace kafin su
Kafin farawa da Schmitt Trigger, ya zama dole ayyana ma'aurata biyu wanda zai zo da amfani don ƙarin fahimtar abin da yake da kuma yadda yake aiki. Ina nufin:
- Kwatanta: A cikin kayan lantarki, comparator shine na'urar da ke kwatanta ƙarfin wuta ko igiyoyi guda biyu kuma ta fitar da siginar dijital wanda ke nuna wanda ya fi girma. Yana da tashoshin shigar da analog guda biyu, da fitarwar dijital na binary guda ɗaya. Wannan yana da mahimmanci a lura, kamar yadda Schmitt trigger wani nau'in kwatancen ne. Bugu da ƙari, wannan kwatancen ya ƙunshi babban fa'ida na musamman na babban riba.
- Ciwon ciki: Hysteresis wani abu ne wanda yanayin tsarin ya dogara da tarihinsa. Misali, maganadisu na iya samun lokuta daban-daban na maganadisu a cikin filin maganadisu dangane da yadda filin ya canza a baya, yana samar da lankwasa hysteresis. Ana lura da wannan kadarorin a cikin kayan ferromagnetic da ferroelectric da abubuwan al'amuran halitta kamar nakasar rubbers da sifofin ƙwaƙwalwar ajiya. Hysteresis yana da alaƙa da canje-canjen da ba za a iya canzawa ba, kamar sauye-sauyen lokaci, kuma yana da yawa a cikin tsarin halitta. Me yasa ya kamata ku san wannan? To, saboda Schmitt Trigger shine da'irar kwatance tare da hysteresis.
Menene Ƙarfafa Schmitt?
Un Schmitt Trigger, wanda kuma aka sani da Schmitt trigger a cikin Mutanen Espanya, na'urar kwatancen lantarki ce wacce ke canza siginar shigar da analog zuwa siginar fitarwa na dijital. Yana yin haka ne ta hanyar amfani da ra'ayi mai kyau don samar da wurin jujjuyawa, ma'ana cewa kofa don sauyawa tsakanin ma'anar "high" da "ƙananan" jihohi ya bambanta don tashi da faduwar siginar shigarwa. Wannan ɗabi'ar ɗabi'a yana hana hawa da sauka maras so kuma yana ba da juriyar juriya don ƙarami ko siginonin shigarwar jitter.
An kirkiro zane a karon farko Otto H. Schmitt a shekara ta 1934, don haka sunansa. Tun daga wannan lokacin, ana amfani da wannan kayan lantarki sosai a cikin aikace-aikacen da yawa kamar yadda za mu gani a gaba. Bugu da kari, ya kamata ku sani cewa yawanci ana lullube shi a cikin da'ira ko guntu, yawanci DIP, kuma galibi ya ƙunshi amplifier aiki (op-amp) Tare da tabbataccen martani ta hanyar resistors, shigarwar da ba ta juyewa ba (+) da kuma shigar da op-amp guda ɗaya ana haɗa su ta hanyar sarkar resistor, kuma ana haɗa ƙarin resistor don ingantaccen martani daga fitarwa zuwa shigar da inverting. .
Amma ga halin hysteritic, Dole ne a ce lokacin da siginar shigarwa ya wuce wani madaidaicin babba, fitowar Schmitt Trigger ya canza zuwa "high", kuma idan siginar shigarwar ya ragu a ƙasa da wani ƙananan ƙananan kofa na daban, fitarwa yana canzawa zuwa "ƙananan". Bambanci tsakanin kofofin biyu ana kiranta taga hysteresis kuma yana da mahimmanci don halayen hysteretic. Wannan yana da fa'idodi yayin da yake guje wa saurin martanin da ba'a so saboda ƙananan hayaniyar ko hayaniya a cikin siginar shigarwa. Saboda haka, yana ba da rigakafi ga amo.
Ana amfani da faɗakarwar Schmitt don inganta amo rigakafi a cikin kewayawa tare da ƙofar shiga guda ɗaya. A wannan yanayin, sigina mai hayaniya kusa da bakin kofa zai iya haifar da saurin canje-canje a cikin abin fitarwa saboda amo. Mai jawo Schmitt, ta hanyar samun ƙofa biyu, yana guje wa canje-canje maras so, tun da siginar hayaniya kusa da bakin kofa yana haifar da canji a cikin fitarwa; Don haifar da wani canji, siginar dole ne ta wuce sauran madaidaicin.
Un m misali Ya ƙunshi haɓakar infrared photodiode wanda ke haifar da sigina mai canzawa tsakanin matsananciyar dabi'u. Ana daidaita wannan siginar tare da matattara mai ƙarancin wucewa, kuma abin da aka tace ana haɗa shi da faɗakarwar Schmitt. Wannan na'urar tana tabbatar da cewa fitarwa kawai yana tafiya daga ƙasa zuwa sama bayan siginar infrared yana motsa photodiode fiye da sanannen lokaci. Da zarar abin faɗakarwa na Schmitt ya yi girma, sai kawai ya dawo ƙasa bayan siginar infrared ya daina jin daɗin photodiode na tsawon fiye da irin wannan lokacin sananne. Wannan yana guje wa sauye-sauye masu ban tsoro da hayaniyar muhalli ke haifarwa. Abubuwan da ke haifar da Schmitt sun zama ruwan dare a cikin juyawa da'irori, kamar su kashe maɓalli.
Yadda Schmitt Trigger ke aiki
Kewaye tare da hysteresis sun dogara ne akan tabbatacce feedback, yana ba da damar canza duk wani da'ira mai aiki a cikin faɗakarwar Schmitt ta hanyar yin amfani da ra'ayi mai kyau tare da ribar madauki fiye da ɗaya. Kyakkyawan amsa ya ƙunshi ƙara wasu ƙarfin fitarwa zuwa ƙarfin shigarwar. Ana iya aiwatar da waɗannan da'irori waɗanda suka haɗa da attenuator, adder, da amplifier da ke aiki azaman kwatance, ta amfani da takamaiman dabaru guda uku.
Dabarun biyu na farko sune versions dual (jeri da a layi daya) na tsarin amsawa na gaba ɗaya. A cikin waɗannan saitunan, ƙarfin fitarwa yana canza ingantaccen bambanci na ƙarfin shigar da kwatancen kwatancen, ko dai ta hanyar 'raguwar ƙofa' ko ta 'ƙara wutar shigar da kewaye'. Waɗannan saitunan sun haɗa ƙofa da kaddarorin ƙwaƙwalwar ajiya cikin kashi ɗaya. Madadin haka, fasaha ta uku ta raba ƙofa da kaddarorin ƙwaƙwalwar ajiya, suna ba da ƙarin sassauci a aiwatar da kewaye.
Utilities da aikace-aikace
Schmitt Triggers za a iya amfani da su don aikace-aikace masu amfani da yawa dangane da tsarin, misali:
- Analog zuwa canjin dijital- Wannan bangaren yana da inganci guda-bit analog-zuwa-dijital Converter. Lokacin da siginar ya kai matakin da aka bayar, yana canzawa daga ƙananansa zuwa babban matsayi.
- Gano matakin- yana da ikon samar da gano matakin. Lokacin yin wannan aikace-aikacen, wajibi ne a yi la'akari da ƙarfin lantarki na hysteresis ta yadda za'a canza ta hanyar ƙarfin da ake buƙata.
- Layi liyafar- Lokacin da aka kawo layin bayanai wanda zai iya ɗaukar hayaniya zuwa ƙofar dabaru, ya zama dole a tabbatar cewa matakin fitarwa na dabaru kawai yana canzawa lokacin da bayanin ya canza ba sakamakon hayaniya da aka ɗaga ba. Yin amfani da faɗakarwa na Schmitt yana ba da hayaniyar kololuwa zuwa kololuwa don isa matakin ɗabi'a kafin tashin hankali ya iya faruwa.
Kamar yadda mafi takamaiman lokuta, za ka iya ganin su a da'irori inda kana so ka kawar da bounces a inji Buttons, a square kalaman janareta, a matakin ganowa, a cikin data line amo kariya da'irori, bugun jini janareta, da kuma shahararrun converters.
Yi amfani azaman oscillator
A Schmitt jawo shi ne mai bistable multivibrator wanda ana iya amfani dashi don aiwatar da wani nau'in multivibrator, da shakatawa oscillator. Ana samun wannan ta hanyar haɗa da'ira mai haɗawa ta RC guda ɗaya tsakanin fitarwa da shigar da abin juyawa Schmitt. Fitowar za ta kasance ci gaba da raƙuman murabba'in murabba'in wanda mitar ta dogara da ƙimar R da C, da madaidaicin maki na Schmitt. Tun da IC guda ɗaya na iya samar da abubuwan da ke haifar da Schmitt da yawa (misali, nau'in 4000 40106 jerin na'urar CMOS ta ƙunshi 6 daga cikinsu), ƙarin ɓangaren IC ɗin za a iya amfani dashi da sauri azaman oscillator mai sauƙi kuma abin dogaro tare da abubuwan waje guda biyu kawai.
A wannan yanayin, ana amfani da faɗakarwa na tushen Schmitt a cikin jujjuyawar tsarin sa. Bugu da ƙari, ana ƙara jinkirin ra'ayi mara kyau tare da haɗin gwiwar RC. Sakamakon haka shine fitarwa ta atomatik daga VSS zuwa VDD kamar yadda capacitor ke cajin daga kofa ɗaya na faɗakarwar Schmitt zuwa wancan.
Pin-fita
Dole ne ku tuna cewa bisa ga samfurin na'ura Zai iya canzawa, don haka ina ba da shawarar cewa koyaushe ku ga takaddar bayanan masana'anta daidai da ƙirar da kuka saya. Koyaya, a matsayin misali, anan muna da guntu 74LS14 TTL tare da jawo 6 a ciki. Don haka, muna da fil ɗin DIP guda ɗaya wanda zai zama na wutar lantarki na Vcc, wani kuma na ƙasa ko GND. Wannan shi ne yadda ake kunna duk abubuwan da ke haifar da wuta, sannan zai zama batun amfani da shigarwa da fitarwa wanda ya dace da ku.
Inda zan siya
A ƙarshe, idan kuna so saya ɗaya daga cikin waɗannan Schmitt Trigger, Kuna iya samun su a cikin shaguna na musamman ko akan dandamalin tallace-tallace na kan layi kamar Amazon:
