Koj tuaj yeem txuas cov LED ncaj qha, tsis muaj qhov tsis kam, tsuas yog rau lub zog siv hluav taws xob nrog lub siab sab hauv. Hauv txhua lwm yam mob, kev txwv tam sim no yog qhov tsim nyog los tiv thaiv diode tsis ua haujlwm. Kev txiav txim siab ntawm tus nqi ntawm qhov txiav tawm tam sim no-txwv tsis pub dhau yog ua los ntawm xam.
Cov Lus Qhia
Kauj ruam 1
Nws tsis yooj yim sua kom txiav txim siab nominal LED tam sim no sib dhos. Qhov ntsuas no ntawm lub cuab yeej yuav tsum tau nug los ntawm tus muag khoom thaum yuav nws. Yog tias koj paub txog hom diode, nkag mus rau hauv ib lub tshuab tshawb nrhiav - muaj caij nyoog tias yuav muaj cov ntaub ntawv siv rau nws, suav nrog cov rated tam sim no.
Kauj ruam 2
Yog tias tsis muaj cov ntaub ntawv hais txog LED, peb tuaj yeem xav tias cov cuab yeej hauv SMD hom rooj plaub muaj cov nominal tam sim no ntawm 3 mA, rau puag ncig 3 hli txoj kab uas hla - 5 mA, rau cov duab plaub hla ntu ntawm 3 los ntawm 5 hli - 10 mA, rau qhov puag ncig ib lub nrog 5 los ntawm 10 mm - 20 mA.
Kauj ruam 3
Lub voltage poob hla ib qho LED yog nyob ntawm nws cov xim. Rau infrared, nws yog 1, 2 V, rau xim liab - 1, 8, rau ntsuab - 2, 2, rau xiav, dawb thiab violet - los ntawm 3 txog 4.
Kauj ruam 4
Txheeb xyuas cov hluav taws xob poob thoob plaws tam sim no-lim tawm cov resistor siv cov qauv hauv qab no: Ur = Up-Ud, qhov twg:
Ur yog qhov kev poob hluav taws xob hla lub resistor, V;
Up - hwj huam muab voltage, V;
Ud - voltage poob hla LED, V.
Kauj ruam 5
Siv Ohm Txoj Cai los laij rau qhov tsis kam ntawm lub resistor. Ua ntej xam, hloov cov nominal tam sim no ntawm LED rau hauv amperes, rau cov uas nws cov nqi, qhia hauv milliamperes, faib los ntawm 1000. Piv txwv, 20 mA = 0.02 A. Tom qab txiav txim siab tus nqi ntawm lub resistor siv cov qauv hauv qab no: R = Ur / Inom, qhov twg:
R - qhov yuav tsum tau tiv thaiv ntawm resistor, Ohm, Ur - voltage poob hla lub resistor, xam raws li cov qauv dhau los, V;
Inom - LED ntsuas tam sim no, A.
Kauj Ruam 6
Kauj ruam kawg yog xam lub zog ntawm tus thev tsis taus. Txhawm rau ua qhov no, ua kom ntau qhov voltage poob hla lub resistor los ntawm qhov tam sim no ntws los ntawm nws (tseem yav dhau los hloov mus rau amperes): P = Ur * Inom, qhov twg:
Ur yog qhov kev poob hluav taws xob hla lub resistor, V;
Inom - qhov ntsuas tam sim no ntawm LED, A. Nws yog qhov siv tau lub hwj chim siab dua, tab sis tsis txhob siv qis qis dua.
Kauj Ruam 7
Txhawm rau kom nce tag nrho qhov kev ua haujlwm ntawm lub zog thaum qhov muab hluav taws xob voltage ntau dhau, LEDs nrog rau cov ntsuas sib npaug tam sim no tuaj yeem txuas rau hauv cov hluav taws xob nyob rau hauv txoj kev uas hais txog 2/3 ntawm cov khoom siv voltage poob rau ntawm cov saw no, thiab li 1/3 ntawm lub resistor. Hauv qhov no, cov teeb meem nominal diode hloov chaw yuav tsum tau ntxiv ua ke ua ntej ua kev suav.
