Chifukwa cha mawonekedwe a VFMa LED, zina za VF zidzasintha ndi kutentha ndi zamakono, zomwe nthawi zambiri sizoyenera kupanga zofanana. Komabe, nthawi zina, tiyenera kuthetsa vuto la kuyendetsa mtengo wa ma LED angapo molumikizana. Mapangidwe awa angagwiritsidwe ntchito pofotokozera.
Dziwani kuti mtengo wa VF uyenera kugawidwa m'makalasi. Ma LED okhala ndi mtengo womwewo wa VF akuyenera kugwiritsidwa ntchito pa chinthu chomwecho momwe angathere. Chogulitsacho chimatha kuwonetsetsa kuti cholakwikacho chili mkati mwa 1mA ndipo LED ili mumkhalidwe wokhazikika.
Kugwiritsa ntchito ma triodes ophatikizika kumatha kusunga mawonekedwe amtundu uliwonseLED yokhazikika. Ma triode awa amapangidwa pansi pa malo otentha omwewo komanso momwe zinthu zimayendera β Mtengo womwewo ukhoza kuwonetsetsa kuti pompopompo iliyonse imakhala yofanana. Gawo lamakono lokhazikika likhoza kupangidwa motere pamene zofunikira sizikhala zapamwamba kwambiri. Magetsi okhazikika kapena voteji ya PWM yokhazikika imayendetsa voteji yokhazikika ya triode kuti ikwaniritse nthawi zonse.
Pogwiritsa ntchito IC yolondola kwambiri ngati gwero lanthawi zonse, R ikhoza kukhazikitsa IC yotulutsa panopa. Pomwe mtengo wa R kukana utsimikiziridwa, ukhoza kusinthidwa ndi kukana kokhazikika. Kugwiritsa ntchito zida zophatikizika zama triode zambiri kumatha kuchepetsa kugwiritsa ntchito IC, motero kumachepetsa mtengo wazopanga.
Linear high-power LED zotulutsa nthawi zonse zitha kugwiritsidwa ntchito limodzi. Pamapangidwe azinthu, nthawi zambiri sitipeza IC yoyendetsa ndi yaposachedwa kwambiri. Nthawi zambiri, ndizosowa kuwona IC yokhala ndi dzina la 2A kapena pamwambapa, ndipo IC yokhala ndi dzina la 2A sangagwiritsidwe ntchito mpaka malire. Chifukwa cha mtengo wa ndondomeko ya IC yaikulu kuposa 1a ndikuti machubu a MOS ali kunja, ndipo dera lakunja la MOS chubu ndilovuta ndipo kudalirika kumachepetsedwa. Kugwira ntchito limodzi ndi njira yabwino yopangira.
DD312 yofananira yofananira imatengedwa kuti iyendetse mwachindunji atatu 6wled. Kuthandizira ma siginecha owongolera a PWM kumafuna kudzipatula koyenera kuti mupewe kusokonezana komanso zovuta zamagalimoto. Mphamvu yamagetsi yamagetsi iyenera kukwaniritsa zofunikira, ndipo musawononge pini ya EN yokwera kwambiri. Nthawi zambiri, IC kupirira voteji imatanthauza katundu ndi magetsi. Ngati palibe chowonetsa kuti chiwongola dzanja chilipo, chonde musapitirire kapangidwe ka 5V.
Kwa mtundu uwu wa kuzindikira, ndiLED yokhazikikapakali pano IC pa malekezero a LED amathanso kupangidwa ndikuyendetsedwa mofanana. M'malo mwake, IC imagwira ntchito yokha ndipo pamapeto pake imagwira ntchito limodzi. Njira ya DC-DC imagwira ntchito pafupipafupi. Tiyenera kuzindikira kuti mawonekedwe a PCB akuyenera kupewa mapangidwe a mtanda. Zosefera zomwe zikutsatiridwa ndi bypass capacitors ziyenera kukhala pafupi ndi IC, ndipo katundu wapano adzaphatikizidwa.
Nthawi yotumiza: Jul-14-2022