LTH-301-23 Photoelectric Interrupter Datasheet - Dimensions 4.0x3.2x2.5mm - Forward Voltage 1.6V - Technical Documentation

1. Muhtasari wa Bidhaa

LTH-301-23 ni moduli ya kompakt ya kukatiza mwanga wa moja kwa moja, iliyoundwa kwa matumizi ya swichi yasiyo ya kugusa. Inachanganya diode inayotoa mwanga wa infrared na transistor ya fotoelektriki ndani ya kifuniko kimoja, zikigawanywa na pengo la kimwili. Kanuni yake ya msingi ya kufanya kazi ni kuzuia mwendo wa mwanga wa infrared kati ya kitoa na kigunduzi, na kusababisha mabadiliko ya hali ya pato la transistor ya fotoelektriki. Hii inafanya iwe inafaa kabisa kwa matumizi yanayohitaji kugundua msimamo, kugundua kitu au swichi ya kikomo bila kugusa kimwili, na hivyo kuondoa uchakavu wa mitambo, na kufikia uaminifu wa juu na kasi ya haraka ya kubadili.

Faida zake kuu ni pamoja na uendeshaji usio wa kugusa, unaotoa maisha marefu ya huduma; wakati wa kukabiliana haraka unaofaa kwa kuhesabu au kugundua kasi; na muundo unaolingana na usakinishaji wa moja kwa moja wa PCB au tundu la kawaida la mstari mbili, na kuwezesha ujumuishaji. Soko lengwa na matumizi ni pana sana, yanajumuisha vifaa vya otomatiki za ofisi (printa, nakala), otomatiki za viwanda (kugundua vitu kwenye mwendo wa mabandari, kugundua msimamo), elektroniki za watumiaji, na aina mbalimbali za vyombo vya kupimia na mifumo ya udhibiti.

2. Uchambuzi wa kina wa Vigezo vya Kiufundi

2.1 Viwango vya Juu Kabisa

Viwango hivi vinaelezea mipaka ya mkazo ambayo inaweza kusababisha uharibifu wa kudumu wa kifaa. Hakuna uhakika wa uendeshaji chini ya hali hizi. Mipaka muhimu ni pamoja na:

• Mwendo wa moja kwa moja wa diodi ya infrared (I_F)): 60 mA. Hii ndiyo mkondo thabiti wa juu unaoweza kupita kwenye LED ya infrared.
• Mwendo wa kilele wa moja kwa moja wa diodi ya infrared): 1 A chini ya hali ya pigo 300 kwa sekunde, upana wa pigo 10 μs. Hii inaruhusu pigo fupi lenye nguvu zaidi kwa matumizi yanayohitaji ishara yenye nguvu zaidi.
• Voltage ya kolekta-emiteri ya fototransistor (V_CEO)): 30 V. Upeo wa juu wa voltage unaoweza kutumiwa kati ya kolekta na emita ya transistor ya pato.
• Safu ya joto la uendeshaji): -25°C hadi +85°C. Hii inafafanua safu ya joto ya mazingira ambayo kifaa kinafanya kazi kwa uaminifu.
• Joto la kuunganisha pini): 260°C kwa sekunde 5 kwa umbali wa 1.6mm kutoka kwa kifurushi. Hii ni muhimu kwa udhibiti wa mchakato wa usanikishaji ili kuzuia uharibifu wa joto.

2.2 Tabia za Umeme na Optics

Vigezo hivi vinabainishwa wakati joto la mazingira (T_A) ni 25°C, na vinafafanua utendaji wa kawaida wa uendeshaji.

2.2.1 Tabia za Ingizo (LED ya Infrared)

• Voltage ya Mbele (V_F)): Thamani ya kawaida ni 1.2V hadi 1.6V wakati mkondo wa mbele (I_F) ni 20 mA. Hii hutumika kukokotoa thamani ya upinzani wa kudhibiti mkondo katika mzunguko wa kuendesha LED.
• Mkondo wa Nyuma (I_R)): Upeo wa 100 μA wakati voltage ya nyuma (V_R) ni 5V. Hii inaonyesha mkondo wa uvujaji wakati LED imewekwa kinyume, ambao ni mdogo sana.

2.2.2 Sifa za Pato (Transista ya Fotoelektriki)

• Voltage ya Kuvunja ya Collector-Emitter (V_(BR)CEO)): Minimum 30V. This ensures the transistor can withstand typical circuit voltages.
• Collector-Emitter Dark Current (I_CEO)): At V_CE=10V, maximum 100 nA. This is the leakage current when the LED is off (no light), determining the signal level in the "off state".
• Collector-Emitter Saturation Voltage (V_CE(SAT))): At I_C=0.2mA and I_FAt I_C=20mA, maximum 0.4V. This is the voltage drop across the transistor when it is fully "on," important for logic-level interfacing.
• On-state collector current (I_C(ON))): At V_CE=5V and I_F=20mA, minimum 0.4 mA. This specifies the minimum available output current when the beam is not blocked, defining the sensor's sensitivity.

2.2.3 Sifa za Kuunganisha (Mfumo)

• Rise time (t_r)): At V_CE=5V, I_C=2mA, R_L=100Ω test conditions, typical 3 μs, maximum 15 μs.
• Fall time (t_f)): Under the same conditions, typical value 4 μs, maximum value 20 μs.

These response times define the switching speed of the output from OFF to ON (rise) and from ON to OFF (fall). The fast switching speed (microsecond level) enables it to detect fast-moving objects or be used in high-speed counting applications.

3. Uchambuzi wa Mviringo wa Utendaji

The datasheet references typical electrical/optical characteristic curves. Although the provided text does not detail specific graphs, standard curves for such devices typically include:

• The forward current vs. forward voltage curve (I_F-V_F)) of the infrared LED: Shows a non-linear relationship, crucial for designing the drive circuit.
• The collector current vs. collector-emitter voltage curve (I_C-V_CE)Under different irradiance (LED current) levels, these output curves show the operating regions of the transistor (cut-off region, active region, saturation region).
• Current Transfer Ratio (CTR) vs. Forward Current curveCTR is the ratio of the phototransistor collector current (I_C) to the LED forward current (I_F). This curve shows the efficiency of optical coupling and how it varies with the drive current.
• Dark current (I_CEO) and On-state current (I_C(ON))) temperature dependence curves

These curves illustrate how performance degrades under extreme temperatures, which is crucial for designing robust systems that operate within specified temperature ranges.

Miviringo hii inawawezesha wasanifu programu kuboresha sehemu ya kufanya kazi, kuelewa usawazishaji wa utendaji, na kuhakikisha utendaji thabiti chini ya hali zote maalum.

4. Taarifa za Mitambo na Ufungaji

4.1 Vipimo vya Ufungaji

• LTH-301-23 inatumia ufungaji wa kawaida wa kuingiza moja kwa moja. Maelezo muhimu ya vipimo kwenye spec sheet:
• Vipimo vyote vinatolewa kwa milimita, na inchi ziko kwenye mabano.
• Uvumilivu wa kawaida ni ±0.25mm (±0.010"), isipokuwa ikiwa sifa maalum inaelezea vinginevyo.

Ufungaji huu umekusudiwa kwa usakinishaji wa moja kwa moja kwenye PCB au kuingizwa kwenye soketi ya kawaida ya safu mbili, na hutoa urahisi wa kukusanyika na utengenezaji wa mfano.

Pengo la kimwili kati ya kifaa cha kutuma na kigunduzi limewekwa ndani ya kifurushi, na linafafanua mwanya unaozuia kupita kwa kitu. Upana halisi wa pengo hili ni maelezo muhimu ya mitambo yanayopatikana kwenye mchoro wa vipimo.

4.2 Kutambua Upeo wa Umeme na Mpangilio wa Pini

Kwa uendeshaji sahihi, utambuzi sahihi wa pini ni muhimu. Kifaa kina pini nne. Kwa kawaida, pini mbili upande mmoja ni za LED ya infrared (anodi na katodi) na pini mbili upande mwingine ni za fototransista (kolekta na emita). Mchoro wa ufungaji kwenye spec sheet utaonyesha wazi pini 1, kwa kawaida kwa alama ya mkato, nukta au ukingo uliopigwa kwenye kifurushi. Jedwali la sifa za umeme linathibitisha kuwa katika usanidi wa emita ya pamoja, anodi ya LED ni chanya na kolekta ya fototransista ya NPN ni chanya.

5. Mwongozo wa Kuunganisha na Kukusanya

Viwango vya juu kabisa vinatoa mwongozo muhimu wa kuunganisha: joto la kuunganisha pini halipaswi kuzidi 260°C kwa muda wa sekunde 5, na kipimo kinachukuliwa umbali wa 1.6mm (0.063") kutoka kwenye kifurushi cha plastiki. Hii ni tahadhari ya kawaida ya kuzuia uharibifu wa epoksi ya ndani au chipu ya semiconductor kutokana na joto kupita kiasi wakati wa kuunganisha kwa mawimbi au kwa mkono.

• Recommendation:
• Use a temperature-controlled soldering iron.
• Minimize the contact time between the soldering iron and the pin.
• For wave soldering, ensure the temperature profile (preheat, soak, peak temperature, time above liquidus) is controlled to meet this requirement.

Avoid applying mechanical stress to the pins during or after soldering.Storage Conditions:

Kifaa kinapaswa kuhifadhiwa ndani ya safu maalum ya joto la uhifadhi -40°C hadi +100°C, kwa upendeleo katika mazingira yaliyokauka na yasiyo na umeme tuli, ili kuzuia unyevunyevu (unaoweza kusababisha "popcorn effect" wakati wa kuunganishwa tena) na uharibifu wa kutokwa na umeme tuli.

6. Mapendekezo ya Matumizi

6.1 Sakiti ya Kawaida ya UtumiziUsanidi unaojulikana zaidi niKizima cha Emitter ya Pamoja_{. LED ya infrared inaendeshwa kupitia kipingamizi cha kudhibiti mkondo (R}limit_{) . Thamani ya kipingamizi huhesabiwa kama R}limit_CC= (V_F- V_F) / I_{. The phototransistor's collector is connected to a pull-up resistor (R}pull-up_{) and the supply voltage, while the emitter is grounded. The output signal is taken from the collector node. When the light beam is not blocked, the transistor turns on, pulling the output voltage low (close to V}CE(SAT)_CC). When the light beam is blocked, the transistor turns off, and the pull-up resistor pulls the output voltage high (to V

).

• 6.2 Design ConsiderationsCurrent Setting_F: Select I based on the required sensitivity and power consumption._F. A higher I _{can provide a higher I}C(ON)
• , but will increase power consumption._{Upinzani wa Mzigo wa Pato (R})pull-up
• ): Thamani yake huathiri kasi ya kubadili na uwezo wa sasa wa pato. Upinzani mdogo hutoa muda wa kupanda kwa haraka zaidi (muda mfupi wa RC) na sasa ya kumwagilia ya juu, lakini hutumia nguvu zaidi wakati transistor inawashwa.Ukinzani wa Mwanga wa Mazingira
• : Kwa sababu hutumia mwanga wa infrared uliomoduli, ina ukinzani mzuri kwa mwanga wengi unaoonekana wa mazingira. Hata hivyo, vyanzo vikali vya mwanga wa infrared (k.m., jua, balbu za incandescent) vinaweza kusababisha kusababisha kwa makosa. Kutumia ishara ya kuendesha LED iliyomoduli na saketi ya kugundua iliyolinganishwa inaweza kuimarisha sana uwezo wa kukinza kelele.Sifa za Kitu
• : Sensor hugundua kitu chochote kisicho wazi kwa urefu wa wimbi la infrared. Ukubwa, kasi na nyenzo za kitu huathiri uadilifu wa ishara.Kulinganisha

: Ili kuhakikisha utendakazi unaotegemewa, unahitaji usawazishaji wa mitambo sahihi kati ya kitu cha kuzuia na mfereji wa sensor.

7. Technical Comparison and Differentiation_{Compared to mechanical micro switches, the LTH-301-23 offers a longer service life (millions vs. thousands of cycles), faster response speed, and silent operation. Compared to reflective optical sensors, transmissive photointerrupters like this one are generally more reliable and less sensitive to changes in the target object's color or reflectivity, as they rely on beam interruption rather than reflection. Its key differentiators within the photointerrupter category are its specific combination of package size, slot width, electrical sensitivity (I}C(ON)

) na mchanganyiko maalum wa kasi ya kubadili haraka, na kufanya iweze kutumika katika matumizi ya kasi ya juu yenye nafasi ndogo.

8. Frequently Asked Questions (FAQ)
Q1: What is the typical operating current for the infrared LED?_FA1: The datasheet uses I

= 20 mA, hii ndio sehemu ya kawaida na ya kuaminika ya kufanya kazi. Inaweza kuendeshwa kwa nguvu ya chini zaidi ili kuokoa umeme, au kwa muda mfupi kuendeshwa kwa nguvu ya juu zaidi (ndani ya mipaka kamili) ili kuongeza nguvu ya ishara.
Q2: Je, pato linawezaje kuunganishwa na kifadhibiti kidogo?_CCA2: Pato la dijiti (linalokuwa chini wakati mwale upo, na juu wakati umepigwa vizuizi) linaweza kuunganishwa moja kwa moja kwenye pini ya ingizo la dijiti ya kifadhibiti kidogo. Hakikisha viwango vya voltage vya pato (juu ni V_{, chini ni V}CE(SAT)

) vinapatana na viwango vya mantiki ya MCU. Kwa kawaida, upinzani wa kuvuta juu unahitajika.
Q3: Je, inaweza kugundua vitu vilivyo wazi?

A3: Kivunja mwanga cha kawaida kinachotumia mwanga wa infrared kinaweza kushindwa kugundua kwa uaminifu vitu vinavyowazi kwa urefu wa wimbi la infrared (kwa mfano, baadhi ya plastiki). Kwa matumizi kama haya, sensorer ya urefu tofauti wa wimbi au kanuni tofauti ya kuhisi inaweza kuhitajika.
Q4: Wakati wa kupanda na wakati wa kushuka una maana gani?_rA4: These times limit the maximum switching frequency. The maximum theoretical frequency is approximately 1/(t_f+ t

). With typical times of 3μs and 4μs, this device can handle frequencies up to tens of kHz, making it suitable for high-speed counting or encoder applications.

9. Operating Principle

An optical interrupter is a transmissive optoelectronic device. It consists of an infrared light source (LED) and a light detector (phototransistor) placed facing each other within a housing, with a precise gap between them. When current flows through the LED, it emits infrared light. This light passes through the gap and strikes the base region of the phototransistor. Photons generate electron-hole pairs in the base region, which effectively acts as base current, turning the transistor on and allowing collector current to flow. When an opaque object enters the gap, it blocks the light path. The photogenerated base current stops, the transistor turns off, and the collector current drops to a very low value (dark current). This on/off change in output current is used as a switching signal.

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