2820-SR3501H-AM Super Red LED Datasheet - Size 2.8x2.0mm - Voltage 2.45V - Power 0.86W - Technical Documentation

1. Product Overview

The 2820-SR3501H-AM series is a high-brightness, surface-mount ultra-red LED specifically designed for demanding automotive lighting applications. This device belongs to a product family engineered to meet stringent automotive-grade reliability and performance standards. Its primary function is to provide a reliable, efficient, and intense red light source for various signal and illumination functions within the vehicle interior.

The core advantages of this LED include compliance with the AEC-Q102 standard, ensuring its robustness in automotive environments, and a typical luminous flux output of up to 45 lumens at standard drive current. The device features a wide viewing angle of 120 degrees, making it suitable for applications requiring broad light distribution. It complies with RoHS, REACH, and halogen-free directives, reflecting adherence to modern environmental and safety regulations.

The target market is specifically automotive lighting, encompassing, but not limited to, interior ambient lighting, center high-mounted stop lights (CHMSL), rear combination lamps, and other signal functions where vivid red color and high reliability are paramount.

2. In-depth Analysis of Technical Parameters

2.1 Luminous and Optical Characteristics

The core of luminous performance is the typical luminous flux (Φ_v) is 45 lumens. This measurement has a tolerance of ±8% and was taken with the thermal pad stabilized at 25°C. The dominant wavelength (λ_d) has a typical value of 632 nm, defining its ultra-red color point, with a specified range from 627 nm to 639 nm and a measurement tolerance of ±1 nm. The spatial light distribution is characterized by a wide viewing angle (2φ) of 120 degrees, with a tolerance of ±5 degrees. This wide beam is ideal for applications requiring good visibility from different angles.

2.2 Electrical Characteristics

Forward Voltage (V_F) is a key electrical parameter, with a typical value of 2.45 V at 350 mA, ranging from 2.00 V to 2.75 V, and a measurement tolerance of ±0.05 V. The device's rated continuous forward current (I_F) can be up to 500 mA, with an absolute maximum of 1500 mA under surge conditions (pulse width ≤10 μs, duty cycle 0.005). It must be noted that this LEDis not designed for reverse operation.provides a dedicated pad pattern (package) for PCB design. This pattern is optimized for forming reliable solder joints during reflow soldering and for efficient heat transfer from the LED thermal pad to the PCB. Following this recommended layout is crucial for mechanical stability, electrical performance, and most importantly, thermal management. The pad design includes exposed thermal vias or copper pour areas to act as heat sinks.

2.3 Thermal Characteristics

Thermal management is crucial for the performance and lifespan of LEDs. The thermal resistance from junction to solder point (R_thJS) Imebainishwa kwa njia mbili: Kipimo halisi kinatoa thamani ya kawaida ya 12.8 K/W (kiwango cha juu cha 16.2 K/W), na kipimo cha umeme kinatoa thamani ya kawaida ya 10 K/W (kiwango cha juu cha 13 K/W). Kiwango cha juu cha joto la kiungo (T_J) ni 150°C. Kifaa kinaweza kufanya kazi na kuhifadhiwa katika anuwai ya halijoto ya mazingira ya -40°C hadi +125°C. Hasa wakati wa kufanya kazi kwa mikondo ya juu zaidi, upoaji joto unaofaa ni muhimu ili kudumisha halijoto la kiungo ndani ya mipaka salama.

2.4 Reliability and Environmental Class

该LED满足多项关键可靠性基准。其ESD敏感度等级为2 kV（人体模型，HBM），这是汽车元件的标准。它根据汽车应用中分立光电器件的全球标准AEC-Q102修订版A进行了认证。此外，它满足硫化物测试标准A1级，表明其能抵抗腐蚀性硫环境。该元件还符合RoHS、REACH标准，且无卤素（Br<900 ppm，Cl<900 ppm，Br+Cl<1500 ppm）。其湿度敏感等级（MSL）为2级。

3. Grading System Description

Ili kuhakikisha uthabiti wa rangi na mwangaza katika uzalishaji, LED zinagawanywa katika daraja tofauti. 2820-SR3501H-AM hutumia viwango vitatu tofauti vya kugawa daraja.

3.1 Kugawa Daraja kwa Flux ya Mwanga

LEDs are grouped based on their light output at 350 mA. The standard bin for this series is F3, with a luminous flux range of 39 lm (min) to 45 lm (max). Other available bins include F4 (45-52 lm) and F5 (52-60 lm). This allows designers to select the appropriate brightness level for their application.

3.2 Kugawa Daraja kwa Voltage ya Mbele

Binning forward voltage aids in circuit design and power supply matching. The bins include 2022 (2.00-2.25 V), 2225 (2.25-2.50 V), and 2527 (2.50-2.75 V). Understanding the V_Fbin helps to more accurately predict power consumption and thermal load.

3.3 Dominant Wavelength Binning

Rangi (wavelength kuu) inadhibitiwa kwa uangalifu kupitia vikundi. Vikundi hivyo vinafafanuliwa kama 2730 (627-630 nm), 3033 (630-633 nm), 3336 (633-636 nm) na 3639 (636-639 nm). Hii inahakikisha tofauti ndogo ya rangi kati ya LED binafsi katika safu, jambo muhimu kwa matumizi ya urembo na ishara.

4. Uchambuzi wa Mkunjo wa Utendaji

4.1 IV Curve na Mwangaza wa Jamaa

The forward current versus forward voltage graph shows a typical exponential relationship. At 350 mA, the typical V_Fis 2.45V. The relative luminous flux versus forward current curve indicates that light output is sublinear at lower currents, becomes more linear as current increases, and tends to flatten near the maximum rated current. This highlights the importance of driving the LED at or near the recommended current for optimal efficiency.

4.2 Temperature Dependence

The performance curve clearly shows the effect of temperature. The curve of relative forward voltage versus junction temperature has a negative slope, meaning V_Fdecreases as temperature increases (typically -2 mV/°C for red LEDs). This can be used for junction temperature monitoring. The curve of relative luminous flux versus junction temperature shows a significant decrease in light output with increasing temperature, a phenomenon known as thermal droop. The curve of relative wavelength versus junction temperature indicates a slight shift in the dominant wavelength with temperature (typically 0.03-0.05 nm/°C for AlInGaP red LEDs), which is usually small for this material system.

4.3 Forward Current Derating and Pulse Handling Capability

The forward current derating curve is crucial for thermal design. It shows the maximum allowable continuous forward current as a function of pad temperature (T_S) function. At the maximum operating T_S125°C, the maximum I_Fis 500 mA. At higher pad temperatures, the current must be derated to prevent exceeding the 150°C junction temperature limit. The permissible pulse handling diagram provides guidance for pulse operation, showing the permissible I for a given pulse width (t_FP) and the peak pulse current (I allowed by the duty cycle (D_p).

4.4 Spectral Distribution

The relative spectral distribution graph confirms the monochromaticity of this super red LED. The emitted light is concentrated in a narrow band around 632 nm, with almost no emission in the blue or green regions. This results in a highly saturated red, making it ideally suited for automotive signal functions that require specified color purity.

5. Mechanical and Packaging Information

5.1 Physical Dimensions

LED hii inatumia kifurushi cha 2820 Surface Mount Device (SMD). Jina linaonyesha ukubwa wa takriban: urefu 2.8 mm, upana 2.0 mm. Michoro halisi ya mitambo inatoa vipimo vya kina, ikiwa ni pamoja na urefu wa jumla, umbo la lenzi, na nafasi ya fremu ya waya. Isipokuwa imebainishwa vinginevyo, uvumilivu kwa kawaida ni ±0.1 mm. Kifurushi hiki kimeundwa kuendana na vifaa vya kukusanyia vibanzi vya otomatiki.

5.2 Recommended Land Pattern

Muundo maalum wa ardhi (footprint) umetolewa kwa ajili ya muundo wa PCB. Muundo huu umeboreshwa kwa ajili ya uundaji thabiti wa viungo vya solder wakati wa kuuza tena na kwa uhamishaji mzuri wa joto kutoka kwa pad ya mafuta ya LED hadi PCB. Kuzingatia muundo huu unaopendekezwa ni muhimu kwa utulivu wa mitambo, utendaji wa umeme, na muhimu zaidi, usimamizi wa joto. Muundo wa pad unajumuisha vias za mafuta zilizo wazi au kumwaga shaba ili kutumika kama kizuizi cha joto.

5.3 Polarity Marking

The mechanical drawing in the datasheet indicates the anode and cathode terminals. Typically, there may be markings on the package, such as a notch, dot, or bevel, to identify the cathode. Correct polarity must be observed during assembly, as reverse connection will cause the device to malfunction and may damage it.

6. Welding and Assembly Guide

6.1 Reflow Soldering Temperature Profile

Inatoa maelezo ya kina ya mkunjo wa joto wa reflow soldering ili kuhakikisha muunganisho thabiti bila kuharibu LED. Mkunjo huu unabainisha vigezo muhimu: mteremko wa joto la awali, muda na joto la kuingizwa, muda juu ya mstari wa kioevu (TAL), kiwango cha juu cha joto, na kiwango cha kupoa. Joto la juu kabisa la kuchomea ni 260°C kwa sekunde 30. Kufuata mkunjo huu ni muhimu ili kuepuka mshtuko wa joto, kutenganishwa kwa tabaka, au kasoro za sehemu za solder.

6.2 Usage Precautions

Vidokezo vya jumla vinajumuisha: kuepuka mkazo wa mitambo kwenye lenzi, kuzuia uchafuzi wa uso wa macho, kutumia taratibu sahihi za usindikaji wa ESD (kwa sababu ya kiwango chake cha 2kV HBM), na kuhakikisha kifaa kimehifadhiwa katika mazingira kavu kabla ya matumizi kulingana na kiwango chake cha MSL 2. Kama inavyoonyeshwa na mkunjo wa kupunguza mzigo, LED haipaswi kufanya kazi chini ya sasa ya 50 mA.

6.3 Masharti ya Uhifadhi

元件应储存在其原始的防潮袋中，并放入干燥剂，温度在-40°C至+125°C之间，处于非腐蚀性环境。一旦袋子打开，MSL 2等级的元件必须在特定时间范围内（通常在<30°C/60% RH下为1年）完成组装，或根据制造商的说明进行重新烘烤，以去除吸收的湿气并防止回流焊期间的“爆米花”效应。

7. Maelezo ya Ufungaji na Uagizaji

7.1 Vipimo vya Ufungaji

LEDs are supplied in tape and reel format, which is standard for automated SMD assembly. The packaging information details reel dimensions, carrier tape width, pocket pitch, and component orientation. This ensures compatibility with standard feeder systems on assembly lines.

7.2 Part Number System

The part number 2820-SR3501H-AM is interpreted as follows:

• 2820Product series and package size (2.8mm x 2.0mm).
• SRColor (Super Red).
• 350: Test current, unit milliampere (350 mA).
• 1: Lead frame type (1 = Gold plated).
• H: Luminance grade (H = High).
• AM: Designated for automotive application grade.

This naming convention allows for precise identification of the component's key attributes.

8. Application Recommendations

8.1 Mazingira ya Kawaida ya Utumiaji

The main application is automotive lighting. Specific uses include:

• External SignalRear lamps, brake lights, high-mounted stop lamps, turn signals.
• Interior lightingInstrument cluster backlighting, switch illumination, ambient lighting, warning indicators.

Its AEC-Q102 certification and sulfur resistance make it suitable for harsh under-hood or exterior locations with exposure to extreme temperatures, humidity, and chemicals.

8.2 Mazingatio ya Ubunifu

Drive Circuit: It is strongly recommended to use a constant current driver instead of a constant voltage source to ensure stable light output and prevent thermal runaway. The driver design should be able to adapt to V_FThe gear range.

Thermal Managementis the most critical aspect of the design. The PCB must provide an adequate thermal path from the LED solder pads to the heat sink or the board's ground plane. Use the provided thermal resistance (R_thJS) and derating curves to calculate the necessary thermal design to keep T_JWeka chini ya 150°C.

Ubunifu wa OpticsPembe ya mtazamo ya digrii 120 inaweza kuhitaji vifaa vya optics vya pili (lensi, baa za mwongozo) kwa ajili ya kuchapa boriti kwa matumizi maalum (kama vile kuunda muonekano wa mwanga sawasawa au ishara iliyolengwa).

9. Technical Comparison and Differentiation

Ikilinganishwa na LED nyekundu za kibiashara za kiwango, mfululizo wa 2820-SR3501H-AM unatoa faida kubwa kwa matumizi ya magari:

• Uthabiti: Uthibitishaji wa AEC-Q102 unahusisha majaribio makali ya mkazo (maisha ya uendeshaji wa joto kali, mzunguko wa joto, uthabiti wa unyevu, n.k.), yanayozidi kwa kiasi kikubwa viwango vya kibiashara.
• Extended Temperature RangeAn operating range of -40°C to +125°C is crucial for automotive environments, whereas commercial LEDs are typically rated up to +85°C.
• Color and Luminous Flux BinningStricter binning ensures consistency in appearance and performance across all units within vehicle lighting assemblies.
• Sulfur resistanceComplies with A1-level sulfide test standards, preventing corrosion from sulfur-containing gases present in certain automotive environments (e.g., from tires or specific seals).
• TraceabilityVipengee vya kiwango cha magari kwa kawaida vinahitaji uwezo mkali wa kufuatilia katika mnyororo mzima wa usambazaji.

Tofauti yake kuu iko katika uthabiti wake ulioidhinishwa kwa mfumo wa magari.

10. Maswali Yanayoulizwa Mara kwa Mara (FAQ)

Swali: Naweza kutumia betri ya gari ya 12V kuendesha LED hii moja kwa moja?
Jibu: Hapana. LED inahitaji kiendesha cha mkondo wa mara kwa mara. Kuunganisha moja kwa moja kwenye 12V kutasababisha mkondo mwingi ulioharibifu na kushindwa mara moja. Ni lazima kutumia mzunguko wa kiendesha (cha mstari au cha kubadili) unaosawazisha mkondo hadi 350 mA (au kiwango kingine kinachohitajika ndani ya vipimo).

Swali: Madhumuni ya fremu ya kuongoza iliyopakwa dhahabu (aina "1") ni nini?
Jibu: Dhahabu ya kufunikwa hutoa mwonekano bora wa kukinga kutu na uwezo bora wa kulehemu kwa muda mrefu, ambayo ni muhimu kwa uaminifu wa muda mrefu katika mazingira magumu ya magari. Pia inahakikisha muunganisho thabiti wa umeme wenye upinzani mdogo.

Swali: Je, unaelejeaje maadili mawili tofauti ya upinzani wa joto (kipimo halisi dhidi ya kipimo cha umeme)?
Jibu: Thamani ya "halisi" (12.8 K/W) ilipimwa moja kwa moja kwa kutumia mbinu ya majaribio ya joto. Thamani ya "umeme" (10 K/W) ilitokana na sifa za voltage ya mbele zinazohisi joto. Kwa muundo wa joto uliojihami, inashauriwa kutumia thamani ya juu ya "halisi" au thamani ya juu maalum (16.2 K/W) katika mahesabu.

Swali: Je, daima inahitajika radiator?
Jibu: Inategemea mkondo wa kuendesha, halijoto ya mazingira na muundo wa PCB. Kwa mkondo kamili wa 500 mA na/au halijoto ya juu ya mazingira, njia bora ya joto (kupitia PCB hadi radiator au eneo kubwa la shaba) ni muhimu kabisa ili kukaa ndani ya mipaka ya halijoto ya kiungo. Katika mikondo ya chini na mazingira baridi, PCB yenyewe inaweza kutosha.

11. Uchambuzi wa Kesi Halisi za Ubunifu

Tukio: Kubuni safu ya taa ya breki ya juu (CHMSL).
The designer needs to create a CHMSL using 10 LEDs. The goals are uniform brightness and color, powered from the vehicle's 12V system, with a maximum solder joint temperature of 100°C.

Steps:

1. Electrical Design: Select a constant current driver capable of providing a total of approximately 3.5A (10 x 350mA). The driver's output voltage must be higher than the sum of the maximum V_Fin the series string. For 10 LEDs in series, V_F(max)=2.75V，驱动器需要>27.5V的输出。或者，使用带镇流电阻的并联串或单独的驱动器。
2. Thermal Design: Use the derating curve, at T_S=100°C, the maximum continuous I_FNi takriban 520 mA, kwa hivyo 350 mA ni salama. Hesabu upinzani wa joto unaohitajika kutoka kiungo hadi mazingira: ΔT = T_J(max)- T_S= 150°C - 100°C = 50°C. Nguvu ya kila LED P_D≈ I_F* V_F= 0.35A * 2.45V = 0.8575W. Required R_thJA≤ ΔT / P_D= 50°C / 0.8575W ≈ 58.3 K/W. Since R_thJSis approximately 12.8 K/W, the PCB and ambient must provide R_thSA≤ 45.5 K/W.
3. Optical/MechanicalPlace the LEDs on the PCB according to the recommended pad layout. Design a light guide or diffuser to mix the light from the 10 discrete sources into a single, uniform light bar as required by regulations.
4. Binning: Specify strict luminous flux (e.g., F3 or F4) and dominant wavelength (e.g., 3033) bins to ensure all 10 LEDs are tightly matched.

12. Kanuni ya Uendeshaji

The 2820-SR3501H-AM is based on the Aluminum Indium Gallium Phosphide (AlInGaP) semiconductor material system. When a forward voltage exceeding the material's bandgap energy is applied to the p-n junction, electrons and holes are injected into the active region. Their recombination releases energy in the form of photons (light). The specific composition of the AlInGaP layer is designed to generate photons with a wavelength concentrated around 632 nm, which the human eye perceives as a saturated red color. An epoxy resin lens encapsulates the semiconductor chip, providing environmental protection and shaping the emitted light into a 120-degree viewing angle.

13. Mwelekeo wa Teknolojia

Trends in automotive LED lighting (including red signal functions) are moving towards higher efficiency (more lumens per watt), higher power density (smaller packages, higher light output), and enhanced reliability. Concurrently, there is a trend towards integrated smart LED drivers (with diagnostic and communication capabilities, e.g., via LIN or CAN bus). Furthermore, the push for standardized, scalable lighting modules is influencing package and optical design. The 2820 package represents a mature, reliable platform, while newer designs may focus on chip-scale packaging (CSP) or integrated multi-chip modules for greater design flexibility and performance.