Kulezi zinsuku, i-PLC ingathola amasiginali enzwane kanye nezinzwa ngaphandle kwe-amplifier, ngakho-ke yini ubumnandi be- "Source" kanye "nokukhipha"? Ukukhishwa kuphela kwe-PLC okuzoba nemiqondo "yomthombo" kanye "nokuvuza".

Eqinisweni, ngaphandle kwe-PLC yaseJapan, akudingekile kwamanye ama-PLCs ukusebenzisa izifinyezo ezinjengokuthi "umthombo" kanye "nokukhipha", kepha i-NPN ingasetshenziswa ngqo.

I-PNP umugqa womphakathi ophansi we-voltage, futhi i-NPN ingumugqa womphakathi we-high-voltage. Uma nje lokhu kuxhumeka kulungile, kubonakala sengathi akunandaba ukuthi imiqondo "yomthombo" kanye "nomsele" babuyiselwa emuva. Kodwa-ke, omunye umqondo "Omuhle Onengqondo kanye Nengqondo Engalungile" futhi akulungile, okuzokwenza ukuthi isiginali ihlushwe.

Ukuqonda okuhle nokunengqondo okungekuhle

Kumasekethe wohlobo lwe-PNP, i-terminal ejwayelekile yokuhlinzekwa kwamandla kanye nesiginali isezingeni eliphansi le-0V. Lapho okokufaka kusezingeni eliphansi, akukho mehluko wamandla we-voltage nge-terminal ejwayelekile, ngakho-ke akukho okukhishwa okushintshiwe kwesiginali (inani ledijithali lingu-0). Kuphela lapho okokufaka kusezingeni eliphakeme, kunomehluko we-voltage nge-terminal ejwayelekile kanye nesiginali yokushintsha esikhulisiwe kungukuphuma kwezinga eliphakeme. Le modi yedijithali (Inani le-Digital lingu-1) elisebenza ngempumelelo lapho isinali lisezingeni eliphakeme libizwa ngokuthi yi-PnP enhle logic.

Emjikelezweni we-NPN, i-terminal ejwayelekile yokuhlinzekwa kwamandla kanye nesiginali isezingeni eliphakeme (isimilo salolu hlelo lokusebenza lwe-amplifier). Lapho okokufaka kusezingeni eliphakeme, akukho mehluko wamandla we-voltage phakathi kokufakwayo nokukhipha, ngakho-ke akukho okuphumayo kwesiginali (inani ledijithali lingu-0). Kuphela lapho okokufaka kusezingeni eliphansi (kwakha i-funnel), kukhona okuphumayo kwesiginali, futhi lesi siginali iyindlela esebenzayo (idijithali iyindlela eyi-1) yedijithali ezingeni eliphansi, elibizwa nge-NPN negative logic.