Bayanin Fasaha na LTST-E681UBWT - SMD LED Blue Diffused Lens - Girman Kunshin - Ƙarfin Lantarki 3.8V - Wutar Lantarki 114mW - Takardun Fasaha na Hausa

1. Bayanin Samfur

Wannan takarda tana ba da cikakkun ƙayyadaddun fasaha na na'urar da ake hawa a saman (SMD) mai fitar da haske (LED). Na'urar tana da tushen haske mai launin shuɗi ta amfani da fasahar InGaN (Indium Gallium Nitride) kuma an lulluɓe ta da ruwan tabarau mai watsawa. An ƙera wannan haɗin don samar da faɗin kusurwar kallo tare da sassauƙaƙƙen fitar da haske, wanda ya dace da aikace-aikacen da ke buƙatar haske mai daidaito maimakon katako mai mai da hankali. Samfurin ya bi ka'idojin RoHS (Ƙuntata Abubuwa Masu Haɗari), wanda ya rarraba shi azaman samfurin kore. Ana ba da shi a cikin kaset ɗin 8mm na masana'antu akan reels na inci 7, wanda ya sa ya dace da kayan aikin haɗawa ta atomatik da tsarin sayar da infrared (IR) na yau da kullun.

2. Bincike Mai Zurfi na Sigogi na Fasaha

2.1 Iyakar Ƙididdiga

Iyakar ƙididdiga tana bayyana iyakokin da za su iya haifar da lalacewa ta dindindin ga na'urar. An ƙayyade waɗannan ƙididdiga a yanayin zafin muhalli (Ta) na 25°C. Matsakaicin yawan watsawar wutar lantarki na ci gaba shine 114 mW. Ƙarfin lantarki na gaba na DC bai kamata ya wuce 30 mA ba a ƙarƙashin yanayin aiki na yau da kullun. Don aikin bugun jini, ana iya yarda da matsakaicin ƙarfin lantarki na gaba na 100 mA, amma kawai a ƙarƙashin sharuɗɗa masu tsauri: cikakken aiki na 1/10 da faɗin bugun jini na 1ms. An ƙididdige na'urar don aiki a cikin kewayon zafin jiki na -40°C zuwa +85°C kuma ana iya adana ta a cikin yanayi daga -40°C zuwa +100°C.

2.2 Halaye na Lantarki da na Gani

An ƙididdige aikin a ƙarƙashin daidaitattun yanayin gwaji a Ta=25°C. Babban sigar gani, ƙarfin haske (Iv), yana da ƙimar al'ada na 900 millicandelas (mcd) a ƙarfin lantarki na gaba (IF) na 30mA, tare da mafi ƙarancin ƙayyadaddun ƙimar 355 mcd. Na'urar tana ba da faɗin kusurwar kallo (2θ1/2) na digiri 120, wanda aka ayyana shi azaman kusurwar da ƙarfin ya ragu zuwa rabin ƙimar axial. A lantarki, matsakaicin ƙarfin lantarki na gaba (VF) shine 3.8V a 30mA, tare da matsakaicin 3.8V. Ƙarfin lantarki na baya (IR) yana iyakance zuwa matsakaicin 10 μA lokacin da aka yi amfani da ƙarfin lantarki na baya (VR) na 5V. Yana da mahimmanci a lura cewa ba a ƙera na'urar don aiki a ƙarƙashin ƙarancin lantarki ba; wannan yanayin gwaji ne don siffanta kawai.

2.3 Halayen Bakan

Kaddarorin bakan suna ayyana ingancin launi na hasken da aka fitar. Matsakaicin tsayin tsayin fitarwa (λP) yawanci shine 468 nanometers (nm). Tsayin tsayin da ya fi rinjaye (λd), wanda shine tsayin tsayin da idon ɗan adam ke gani don ayyana launi, yana faɗowa cikin kewayon 465 nm zuwa 475 nm lokacin da aka motsa shi a 30mA. Ramin rabin layin bakan (Δλ), ma'auni na tsaftar launi, yawanci shine 25 nm.

3. Bayanin Tsarin Binning

Don tabbatar da daidaito a aikace-aikace, ana rarraba LED zuwa kwandon shara bisa mahimman sigogi. Wannan tsarin yana ba masu ƙira damar zaɓar abubuwan da suka dace da takamaiman buƙatun juzu'i don kewayon su.

3.1 Binning Ƙarfin Lantarki na Gaba

Ƙarfin lantarki na gaba (VF) ana binning shi cikin matakan 0.2V. Lambobin bin suna kama daga D7 (2.8V - 3.0V) zuwa D11 (3.6V - 3.8V). Juzu'in a cikin kowane kwandon shara shine +/-0.1V. Zaɓin LED daga kwandon shara na ƙarfin lantarki ɗaya yana da mahimmanci don samun daidaitaccen haske lokacin da aka haɗa na'urori da yawa a layi daya ba tare da kowane resistors na iyakancewar yanzu ba.

3.2 Binning Ƙarfin Hasken

Ƙarfin haske an rarraba shi zuwa kwandon shara tare da ƙaruwar ƙimar ƙima. Kwandon shara sune T2 (355-450 mcd), U1 (450-560 mcd), U2 (560-710 mcd), da V1 (710-900 mcd). Juzu'in akan kowane kwandon shara na ƙarfi shine +/-11%. Wannan binning yana ba da damar daidaita haske a cikin tsararrun LED da yawa.

3.3 Binning Tsayin Tsayin da ya fi Rinjaye

Tsayin tsayin da ya fi rinjaye, wanda ke ƙayyade launin shuɗi da ake gani, an rarraba shi zuwa kewayon biyu: AC (465.0 nm - 470.0 nm) da AD (470.0 nm - 475.0 nm). Juzu'in kowane kwandon shara shine +/- 1nm, yana tabbatar da daidaiton launi mai tsauri.

4. Bincike na Lankwasa Aiki

Yayin da aka ambaci takamaiman bayanan hoto a cikin takardar bayanin (misali, Hoto na 1 don fitarwa mai girma, Hoto na 5 don kusurwar kallo), lankwasan al'ada don irin wannan na'urar zai nuna mahimman alaƙa. Waɗannan yawanci sun haɗa da ƙarfin lantarki na gaba da ƙarfin lantarki na gaba (lankwasa I-V), wanda ke nuna alaƙar ƙima da taimakawa wajen ƙirar direba. Ƙarfin haske mai alaƙa da lankwasa ƙarfin lantarki na gaba yana nuna yadda fitar da haske ke ƙaruwa tare da ƙarfin lantarki, sau da yawa a cikin yanki kusa da layi kafin inganci ya ragu a manyan ƙarfin lantarki. Lankwasa rarraba ƙarfin bakan zai nuna tattara ƙarfin haske a kusa da kololuwar 468nm tare da ƙayyadaddun rabin faɗin 25nm. Fahimtar waɗannan lankwasan yana da mahimmanci don inganta aikin LED a cikin takamaiman aikace-aikace, kamar saita daidaitaccen ƙarfin lantarki don cimma haske da inganci da ake so.

5. Bayanin Injiniya da Kunshi

5.1 Girman Kunshin Na'ura

LED ya yi daidai da daidaitattun girman kunshin SMD na EIA. An ba da cikakkun zane-zane na injiniya a cikin takardar bayanin, suna ƙayyade tsayi, faɗi, tsayi, tazarar jagora, da lissafin ruwan tabarau. Duk girmansu suna cikin millimeters, tare da juzu'i na gabaɗaya na ±0.2mm sai dai idan an ƙayyade wani abu. An haɗa ruwan tabarau mai watsawa cikin kunshin, yana ƙayyade ƙayyadaddun halayen gani na ƙarshe.

5.2 Tsarin Ƙasa na PCB da aka ba da shawarar

An ba da shawarar tsarin kafa na'urar da aka buga (PCB) don duka tsarin sayar da infrared da tururi. Yin bin wannan tsarin ƙasa yana da mahimmanci don samun haɗin gwiwa mai dogaro, daidaitaccen daidaitawa, da ingantaccen zubar da zafi yayin aikin sayarwa. Ƙirar kafa tana tabbatar da isasshen ƙarar solder kuma tana hana matsaloli kamar kabari.

5.3 Gano Polarity

Kamar duk diodes, LED yana da anode da cathode. Kunshin ya haɗa da alamomi ko fasali (kamar tsaga, ɗigo, ko yanke kusurwa) don gano fil ɗin cathode. Dole ne a lura da daidaitaccen polarity yayin haɗawa don tabbatar da cewa na'urar tana aiki. Yin amfani da ƙarancin lantarki na baya zai iya lalata LED.

6. Jagororin Sayarwa da Haɗawa

6.1 Bayanin Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar Siffar

The datasheet references a suggested IR reflow profile compliant with the J-STD-020B standard for lead-free soldering. A generic profile is provided, with key parameters including a pre-heat temperature of 150-200°C, a pre-heat time of up to 120 seconds maximum, a peak temperature not exceeding 260°C, and a total time above liquidus (soldering time) of 10 seconds maximum. It is emphasized that the actual profile must be characterized for the specific PCB design, components, solder paste, and oven used.

.2 Storage Conditions

Proper storage is vital to maintain solderability. Unopened, moisture-proof bags with desiccant should be stored at ≤30°C and ≤70% Relative Humidity (RH), with a shelf life of one year. Once the original packaging is opened, the components should be stored at ≤30°C and ≤60% RH. Components exposed to ambient conditions for more than 168 hours (7 days) should be baked at approximately 60°C for at least 48 hours before soldering to remove absorbed moisture and prevent "popcorning" damage during reflow.

.3 Cleaning

If cleaning after soldering is necessary, only specified solvents should be used. The datasheet recommends immersing the LED in ethyl alcohol or isopropyl alcohol at normal temperature for less than one minute. The use of unspecified or aggressive chemical cleaners can damage the plastic package and lens.

. Packaging and Ordering Information

The standard packaging consists of 8mm wide embossed carrier tape that holds the LEDs. The tape is wound onto 7-inch (178mm) diameter reels. Each full reel contains 2000 pieces. For quantities less than a full reel, a minimum packing quantity of 500 pieces is specified for remainders. The packaging follows ANSI/EIA-481 specifications. The part number LTST-E681UBWT uniquely identifies this specific variant: blue color, diffused lens, with the defined electrical and optical bins.

. Application Notes and Design Considerations

.1 Drive Method

LEDs are current-driven devices. To ensure uniform brightness and prevent current hogging, it is strongly recommended to use a series current-limiting resistor for each LED, especially when connecting multiple LEDs in parallel. Driving the LED directly from a voltage source without current regulation is not advised, as small variations in forward voltage can lead to large differences in current and brightness, and potentially overcurrent failure.

.2 Thermal Management

Although the power dissipation is relatively low (114mW max), proper thermal design extends LED life and maintains stable light output. The maximum operating junction temperature is a key factor. Ensuring adequate PCB copper area for heat sinking, avoiding placement near other heat sources, and adhering to the specified current limits are essential practices.

.3 Application Scope

This LED is intended for use in ordinary electronic equipment, including office equipment, communication devices, and household appliances. For applications requiring exceptional reliability where failure could jeopardize safety (e.g., aviation, medical devices, transportation systems), additional qualification and consultation with the component manufacturer are mandatory.

. Technical Comparison and Differentiation

The primary differentiating factors for this LED are its combination of a blue InGaN chip with a diffused lens, resulting in a wide 120-degree viewing angle. Compared to clear-lens LEDs, the diffused lens provides a more uniform, softer light emission, reducing glare and hotspots. The specific binning structure for voltage, intensity, and wavelength allows for high-precision selection in color- and brightness-sensitive applications. Its compatibility with standard IR reflow processes and tape-and-reel packaging makes it a drop-in solution for automated, high-volume manufacturing lines.

. Frequently Asked Questions (FAQ)

Q: Can I drive this LED without a current-limiting resistor?

A: No. An LED must be driven with a controlled current. A series resistor is the simplest method to set the current when using a voltage source. Without it, the current is determined by the power supply's voltage and the LED's dynamic resistance, which is very low and can lead to thermal runaway and destruction.

Q: What is the difference between peak wavelength and dominant wavelength?

A: Peak wavelength (λP) is the wavelength at which the spectral power output is maximum (468nm here). Dominant wavelength (λd) is derived from the CIE chromaticity diagram and represents the single wavelength that the human eye perceives as the color of the light (465-475nm here). For a monochromatic source like a blue LED, they are often close.

Q: Why is storage humidity so important?

A: SMD plastic packages can absorb moisture from the air. During the high-temperature reflow soldering process, this trapped moisture can vaporize rapidly, creating internal pressure that can crack the package or delaminate internal bonds—a phenomenon known as "popcorning." The specified storage and baking procedures prevent this.

. Practical Application Examples

Example 1: Status Indicator Panel:An array of these LEDs can be used behind a translucent or frosted panel to create uniform blue status backlighting for buttons or icons on a consumer electronics device. The wide viewing angle ensures visibility from various positions.

Example 2: Decorative Lighting:Multiple LEDs can be spaced along a strip to create ambient blue accent lighting. The diffused lens helps blend individual points of light into a more continuous glow. Designers must calculate the appropriate series resistor value based on the supply voltage (e.g., 5V or 12V) and the desired forward current (e.g., 20mA for lower power/longer life or 30mA for maximum brightness).

. Operating Principle Introduction

This LED is based on a semiconductor chip made of InGaN. When a forward voltage is applied across the p-n junction, electrons and holes are injected into the active region. When these charge carriers recombine, they release energy in the form of photons (light). The specific bandgap energy of the InGaN material determines the wavelength of the emitted photons, which in this case is in the blue region of the visible spectrum. The diffused lens, made of epoxy or silicone, contains scattering particles that randomize the direction of the emitted light, broadening the beam angle and softening its appearance.

. Technology Trends

The underlying technology for blue LEDs, InGaN, was a groundbreaking development that enabled white LEDs (via phosphor conversion) and full-color displays. Current trends in SMD LED technology focus on increasing luminous efficacy (more light output per watt of electrical input), improving color rendering index (CRI) for white LEDs, achieving higher power densities in smaller packages, and enhancing reliability under higher temperature and current stress. Packaging innovations also aim for better thermal management and more precise optical control. The device described represents a mature, cost-effective implementation of this core technology for general indicator and lighting applications.