Bayanin Fasaha na LED LTE-4238 Mai Fitowa da Haske na Infrared - Tsawon Zango 880nm - Halin Yanzu na Gaba 100mA - Ragewar Wutar Lantarki 150mW - Takardun Fasaha na Hausa

1. Bayanin Samfur

LTE-4238 babban LED ne mai fitar da haske na infrared (IR) wanda aka ƙera don aikace-aikacen da ke buƙatar ingantaccen haske na infrared mai ƙarfi. Babban aikinsa shine fitar da hasken da ba a iya gani ba a mafi girman tsawon zango na 880 nanometers, wanda ya sa ya dace da tsinkaya, sarrafa nesa, da tsarin sauya haske. Babban fasalin shine daidaitawar injiniya da tsarin haske tare da takamaiman jerin na'urorin gani na lantarki (phototransistors), yana tabbatar da mafi kyawun aiki a cikin nau'ikan mai karɓa da mai fitarwa don ingantaccen watsa sigina.

2. Bincike Mai Zurfi na Ma'auni na Fasaha

2.1 Iyakar Ma'auni Mafi Girma

An ƙididdige na'urar don aiki a cikin ƙayyadaddun iyakokin muhalli da na lantarki don tabbatar da tsawon rayuwa da aminci. Matsakaicin halin yanzu na ci gaba shine 100 mA, tare da ikon halin yanzu na kololuwa na 2 A a ƙarƙashin yanayin bugun jini (300 pps, 10 µs faɗin bugun jini). Matsakaicin raguwar wutar lantarki shine 150 mW a yanayin yanayi (T_A) na 25°C. Kewayon zafin aiki daga -40°C zuwa +85°C, yayin da kewayon ajiya ya faɗaɗa daga -55°C zuwa +100°C. Na'urar na iya jure ƙarfin lantarki na baya har zuwa 5 V. Don haɗawa, ana iya solder igiyoyin a 260°C na tsawon lokaci na 5 seconds, wanda aka auna 1.6mm daga jikin fakitin.

2.2 Halaye na Lantarki & Na Gani

An ƙayyade mahimman ma'auni na aiki a T_A=25°C da halin yanzu na gaba (I_F) na 20 mA. Ƙarfin haske (I_E) yawanci shine 4.81 mW/sr, yana nuna fitowar ƙarfin haske a kowane kusurwa mai ƙarfi. Matsakaicin hasken da ke faruwa (E_e) shine 0.64 mW/cm². Ƙarfin lantarki na gaba (V_F) yawanci yana tsakanin 1.3V zuwa 1.8V. An ayyana halayen tsarin haske ta hanyar tsayin zango na fitarwa mafi girma (λ_Peak) na 880 nm da rabin faɗin tsarin haske (Δλ) na 50 nm, yana ayyana ƙunƙuntaccen band ɗin hasken da aka fitar. Halin yanzu na baya (I_R) shine matsakaicin 100 µA a ƙarfin lantarki na baya (V_R) na 5V. Kusurwar kallo (2θ_1/2) shine digiri 20, yana bayyana faɗawar kusurwar hasken da aka fitar inda ƙarfin ya faɗi zuwa rabin ƙimar kololuwa.

3. Binciken Lanƙwan Ayyuka

Bayanin fasaha yana ba da jadawali da yawa da ke kwatanta halayen na'urar a ƙarƙashin yanayi daban-daban.

3.1 Rarraba Tsarin Tsarin Haske

Hoto na 1 yana nuna matsakaicin ƙarfin haske dangane da tsawon zango. Lanƙwan yana tsakiya a 880 nm tare da rabin faɗi na yau da kullun na 50 nm, yana tabbatar da yanayin fitarwar IR mai daidaitawa don tacewa da ingantaccen ganowa.

3.2 Halin Yanzu na Gaba da Yanayin Yanayi

Hoto na 2 yana nuna raguwar matsakaicin halin yanzu na gaba da aka yarda yayin da yanayin yanayi ke ƙaruwa. Wannan jadawali yana da mahimmanci don ƙirar sarrafa zafin jiki, yana tabbatar da cewa na'urar tana aiki a cikin yankinta na aiki mai aminci (SOA) a ƙarƙashin duk yanayin muhalli.

3.3 Halin Yanzu na Gaba da Ƙarfin Lantarki na Gaba

Hoto na 3 yana kwatanta halayen IV (halin yanzu-ƙarfin lantarki) na diode. Wannan alaƙar da ba ta layi ba tana da mahimmanci don ƙirar da'irar tuƙi, ƙayyade ƙarfin lantarki da ake buƙata don cimma takamaiman halin yanzu na aiki.

3.4 Matsakaicin Ƙarfin Haske Dangane da Yanayin Yanayi & Halin Yanzu na Gaba

Hotuna na 4 da 5 suna nuna yadda ƙarfin fitarwa na gani ke canzawa tare da zafin jiki da halin yanzu na tuƙi. Fitarwa yawanci yana raguwa tare da hawan zafin jiki (Hoto na 4) kuma yana ƙaruwa da ƙarfi tare da halin yanzu na gaba (Hoto na 5), yana nuna ciniki tsakanin fitarwa, inganci, da kayan aikin zafi.

3.5 Tsarin Rarraba Haske

Hoto na 6 jadawali ne na polar wanda ke nuna rarraba sararin samaniya na hasken da aka fitar. An tabbatar da kusurwar kallo na digiri 20, yana nuna bayanin katako wanda yake mai da hankali sosai, wanda ke da fa'ida ga aikace-aikacen haske mai jagora.

4. Bayanin Injiniya & Fakitin

4.1 Girman Fakitin

Na'urar tana amfani da daidaitaccen fakitin LED tare da flange. Mahimman girma sun haɗa da girman jiki, tazarar jagora, da iyakokin tsinkaya. Duk girma ana bayar da su a cikin millimeters tare da daidaitaccen haƙuri na ±0.25mm sai dai idan an faɗi. Ana auna tazarar jagora a wurin da igiyoyin suka fita daga jikin fakitin. Ana ba da izinin matsakaicin tsinkaya na resin a ƙarƙashin flange na 1.0mm. Dole ne injiniyoyi su koma cikin cikakken zanen injiniya (wanda aka nuna a cikin PDF) don daidaitaccen sanyawa da ƙirar sawun ƙafa akan allunan da'ira (PCBs).

4.2 Gano Bambancin Ƙarfin Lantarki

Daidaitattun ƙa'idodin bambancin ƙarfin lantarki na LED suna aiki, yawanci ana nuna su ta gefe mai lebur akan fakitin ko ta igiyoyi masu tsayi daban-daban (anode ya fi cathode tsayi). Dole ne a tabbatar da takamaiman alama daga zanen fakitin don tabbatar da daidaitaccen alkibla yayin haɗawa, hana lalacewar karkatar da baya.

5. Jagororin Solder da Haɗawa

The absolute maximum rating for lead soldering temperature is 260°C for 5 seconds, measured 1.6mm (0.063") from the package body. This rating is compatible with standard lead-free reflow soldering profiles (e.g., IPC/JEDEC J-STD-020). It is crucial to adhere to this limit to prevent thermal damage to the internal semiconductor die, wire bonds, or the epoxy lens material. Preheating is recommended to minimize thermal shock. Devices should be stored in a dry, controlled environment as per moisture sensitivity level (MSL) guidelines, which should be obtained from the manufacturer's handling instructions.

. Application Suggestions

.1 Typical Application Scenarios

This IR emitter is ideal for applications including: optical encoders and position sensors, infrared remote control transmitters, object detection and proximity sensing, industrial automation light curtains, and optical data transmission links. Its matching to specific phototransistors makes it particularly valuable in reflective or transmissive optocoupler designs where alignment and spectral response are critical.

.2 Design Considerations

Drive Circuitry:A current-limiting resistor is mandatory when driving with a voltage source to set the desired I_Fand prevent thermal runaway. The resistor value is calculated using R = (V_supply- V_F) / I_F. For pulsed operation at high peak currents (up to 2A), a transistor switch (e.g., MOSFET) driven by a pulse generator is required.
Thermal Management:The 150 mW power dissipation limit must be respected. At high ambient temperatures or high continuous currents, the junction temperature will rise, potentially reducing output intensity and device lifespan. Proper PCB layout with adequate copper area for heat sinking may be necessary.
Optical Design:The 20-degree viewing angle provides a focused beam. For wider coverage, a diffuser lens may be needed. For maximum coupling efficiency with a matched photodetector, ensure proper mechanical alignment and consider potential sources of ambient IR noise (sunlight, incandescent bulbs).

7. Technical Comparison & Differentiation

The LTE-4238's primary differentiation lies in itshigh radiant intensity (4.81 mW/sr typical)and itsspecific selection for matched performance with companion phototransistors. Compared to generic IR LEDs, this preselection ensures tighter tolerances in paired optoelectronic systems, leading to more consistent sensitivity, lower cross-talk, and improved signal-to-noise ratio. The 880 nm wavelength is a common standard, offering a good balance between silicon photodetector sensitivity and lower visibility compared to 940 nm sources.

8. Frequently Asked Questions (FAQs)

Q: What is the purpose of the peak forward current rating (2A) if the continuous current is only 100mA?
A: The peak rating allows for very short, high-current pulses. This is essential for applications like remote controls or data transmission where high instantaneous optical power is needed for range or speed, but the average power (and heat) remains low.

Q: How does ambient temperature affect performance?
A: As temperature increases, the forward voltage typically decreases slightly, the radiant output decreases (as shown in Fig. 4), and the maximum allowable continuous current must be derated (Fig. 2). Design must account for these variations.

Q: Can I drive this LED directly from a microcontroller GPIO pin?
A: Possibly, but with caution. A GPIO pin might source 20-50mA. You must use a series resistor to limit the current to the desired I_F(e.g., 20mA) and ensure the total current does not exceed the microcontroller's pin and package limits. For higher currents or pulses, an external driver transistor is required.

Q: What does "spectrally matched" mean?
A: It means the emission spectrum of this IR LED is optimized to align with the peak spectral sensitivity of its paired phototransistor. This maximizes the detected signal strength for a given emitted power.

9. Practical Design Case Study

Scenario: Designing a Proximity Sensor.The goal is to detect an object within 10 cm. The system uses an LTE-4238 IR emitter and a matched phototransistor placed side-by-side, facing the same direction (reflective sensing mode).
Implementation:The LED is driven with 50 mA pulses (within the continuous rating) at a 1 kHz frequency. A current-limiting resistor sets this bias. The phototransistor's collector is connected to a pull-up resistor and an amplifier/filter circuit. When an object is within range, IR light reflects back into the phototransistor, causing its collector voltage to drop. This signal is then conditioned and fed into a comparator or microcontroller ADC to trigger a detection event.
Key Calculations:The drive resistor value is calculated based on a 5V supply and a V_Fof ~1.5V: R = (5V - 1.5V) / 0.05A = 70 Ohms (use 68 Ω standard value). Power dissipation in the LED: P = V_F* I_F= 1.5V * 0.05A = 75 mW, which is well below the 150 mW maximum at 25°C.

10. Operating Principle Introduction

An infrared LED is a semiconductor p-n junction diode. When a forward voltage is applied, electrons from the n-region and holes from the p-region are injected into the junction region. When these charge carriers recombine, energy is released in the form of photons (light). The specific wavelength of 880 nm is determined by the bandgap energy of the semiconductor materials used (typically aluminum gallium arsenide, AlGaAs). The emitted light is incoherent and falls within the near-infrared spectrum, invisible to the human eye but easily detectable by silicon-based photodetectors.

11. Technology Trends

The trend in IR emitters for sensing continues toward higher power density and efficiency in smaller packages. This enables longer detection ranges and lower system power consumption. There is also a move toward integrated solutions, combining the emitter, driver, and sometimes the detector into a single module with digital interfaces (I2C, SPI). Furthermore, advancements in wafer-level packaging (WLP) and chip-scale packaging (CSP) are reducing the size and cost of discrete optoelectronic components while improving reliability. The fundamental principle of operation remains, but the integration and performance per unit volume are steadily increasing.