Ib qho LED tuaj yeem teeb siv ib qho ntawm ob txoj hauv kev: txoj kev teeb pom kev zoo li qub, uas qhov tam sim no tsis tu ncua yog cov khoom siv txuas ntxiv mus rau lub sijhawm, thiab txoj kev teeb pom kev zoo nyob rau hauv uas tam sim no tau noj hauv ON-OFF pulses tas li. Thaum lub sijhawm ON-OFF luv luv, lub teeb pom kev zoo tshwm sim rau tib neeg lub qhov muag li teeb pom kev zoo li qub. Daim duab 7 qhia txog kev ua haujlwm sib piv ntawm cov teeb pom kev zoo li qub thiab lub teeb pom kev zoo, uas qhia qhov tsis tu ncua rau cov circuits tiag tiag uas siv cov teeb pom kev zoo li qub thiab cov teeb pom kev zoo.
Daim duab 7 (a) thiab (b) – Cov teeb pom kev zoo li qub thiab cov teeb pom kev zoo dynamic tsav piv txwv.
Xaiv Ib Txoj Kev Teeb Pom Kev
Cov teeb pom kev zoo li qub thiab cov teeb pom kev zoo dynamic feem ntau yog siv rau hauv cov ntawv hauv qab no.
Daim ntawv thov Saib lub kaum ntse ntse 2?1/2
High-Brightness LED cov ntaub ntawv vaj huam sib luag 15 ° txog 30 °
Daim ntawv thov teeb liab 8 ° rau 30 °
Tsawg-Brightness LED cov ntaub ntawv vaj huam sib luag 30 ° txog 120 °
Narrow-Direction qhia 30 ° txog 60 °
Qhov taw qhia dav dav 60 ° txog 120 °
Automotive nres teeb 20 ° txog 50 °
Automotive dashboard nqaim directionality 20 ° txog 60 °
Automotive dashboard dav directionality 60 ° txog 120 °
Automotive dashboard dav directionality 60 ° txog 120 °
Dynamic Lighting zaus
Txhawm rau ua kom lub teeb pom kev zoo tshwm sim tsis tu ncua (rau cov neeg soj ntsuam nyob ruaj khov), siv lub teeb pom kev zoo. Txawm li cas los xij, yog tias lub teeb pom kev zoo poob qis dua tus nqi, qhov muag liab qab yuav sau npe flickering. Nyob rau hauv cov ntaub ntawv ntawm sine yoj teeb pom kev zoo (tam sim no dav siv) los yog square-wave teeb pom kev zoo, flickering tshwm sim thaum lub zaus ntog mus rau hauv qab 50 Hz; nyob ib ncig ntawm 40 Hz, flashing tuaj yeem pom meej. Yog li ntawd, kom tsis txhob muaj teeb meem, xaiv lub teeb pom kev zoo ntawm tsawg kawg yog 100 Hz. Thaum tus neeg soj ntsuam raug jolted (piv txwv li, yog tias nws caij tsheb lossis taug kev) lossis raug thaij los ntawm lub koob yees duab ntawm qee yam, flickering yuav pom tseeb, txawm tias lub teeb pom kev zoo siab heev. Xaiv lub teeb pom kev zoo raws li daim ntawv thov.
Teeb pom kev zoo
Lub voj voog hauv daim duab 7(a) qhia txog ib qho piv txwv ntawm cov teeb pom kev zoo li qub hauv lub teeb LED siv los ua qhov taw qhia. Cov yam ntxwv ntawm LED teeb yog ua raws li cov ntaub ntawv kev qhia hauv cov ntawv txuas ntxiv ntawm qhov kawg ntawm Daim Ntawv Qhia Daim Ntawv Thov no. Kev Ua Haujlwm: Thaum teeb lub teeb ci LED siv 10-mA rau pem hauv ntej tam sim no, suav cov hluav taws xob rau pem hauv ntej (uas yuav tsum yog kwv yees li 2V) siv cov duab teeb pom kev zoo ntawm LED (Forward Voltage - Forward Current). Tsim: Nrog rau lub hwj chim mov voltage (Vcc) ntawm 5 V thiab ib tug tsis kam R raws li qhia nyob rau hauv daim duab 7, lub voltage nco Vr yog: Vr=Vcc – (forward voltage)=5.0 – 2.0=3.0 V. Yog li ntawd, thaum ib tug tam sim no ntawm 10 mA yog khiav mus rau lub resistor, qhov tsis kam R yog: R=3V / 10 mA=300 W. Kev lees paub: Tom qab xam qhov tsis kam R, xyuas raws li hauv qab no: Puas muaj teeb meem yog tias lub zog hluav taws xob hloov pauv? xaiv raws li tus nqi ntawm R qhov ze tshaj tus nqi tiv thaiv ntawm ib qho LED hauv LED series.
Lub teeb pom kev zoo
Rau dynamic (mem tes) teeb pom kev zoo, bipolar transistors, FETs, thiab siab ICs feem ntau yog siv. Lub voj voog hauv daim duab 7 (b) qhia txog ib qho piv txwv ntawm lub teeb pom kev zoo. Lub transistor siv nyob rau hauv Circuit Court yog 2SA1298 (Y) transistor, LED teeb rau pem hauv ntej tam sim no yog 80 mA, thiab lub hwj chim mov voltage (Vcc) yog 5 V.
Daim duab 13 - 2SA1298 Transistor yam ntxwv
Kev Ua Haujlwm: Lub hauv paus tam sim no (Lb) siv rau 80-mA transistor collector tam sim no (Ic) yog li 1 mA, raws li cov yam ntxwv nkhaus hauv daim duab 13. Txij li thaum lub transistor voltage Vbe feem ntau yog 0.7 V, qhov tsis kam Rb hauv Circuit Court. Daim duab 7 (b) yog: Rb=(5 - 0.7)V / 1 mA=4.3 ohms. Setting Ib to 2 mA to stabilize the circuit results in: Rb=(5 – 0.7)V/2 mA=2.15 kohms. Yog li, qhov tsis kam ntawm 2.2 kohms yog txaus.
