SMD LED 19-21 Deep Red Light Datasheet - Dimensions 2.0x1.25x0.8mm - Voltage 1.7-2.3V - Power 60mW - Chinese Technical Documentation

1. Product Overview

Bu belge, 19-21 paketleme formunu kullanan kompakt yüzey montajlı derin kırmızı LED'in özelliklerini ayrıntılı olarak açıklamaktadır. Bu bileşen, modern otomatik montaj süreçleri için tasarlanmış olup, devre kartı alanı kullanımı ve tasarım küçültme açısından belirgin avantajlar sunar. Ana uygulaması, küçük boyutlu paketleme içinde elde ettiği yüksek parlaklık ve güvenilir performansı sayesinde çeşitli elektronik cihazlarda gösterge ışığı veya arka aydınlatma kaynağı olarak kullanılmaktır.

1.1 Core Features and Advantages

The key advantages of this LED stem from its SMD (Surface Mount Device) structure. Compared to traditional leaded components, it enables:

• 减小电路板尺寸 & 提高密度：The compact 19-21 package allows for tighter component placement, enabling more compact PCB design.
• Compatible with automated production:Available in 8mm carrier tape and 7-inch reels, fully compatible with high-speed placement equipment, simplifying the manufacturing process.
• Environmental Compliance:产品无铅，符合 RoHS 和欧盟 REACH 法规，并满足无卤素标准（Br <900ppm，Cl <900ppm，Br+Cl <1500ppm）。
• High Solder Joint Reliability:Suitable for infrared and vapor phase reflow soldering processes.

1.2 Target Applications

This LED is suitable for various applications requiring reliable red indicator or backlight, including:

• Backlighting for instrument panels, switches, and symbols.
• Status indicator lights and backlighting in communication equipment (e.g., telephones, fax machines).
• General backlight for LCD panels.
• General indicator lights for consumer and industrial electronics.

2. Technical Parameter Analysis

This section provides a detailed and objective interpretation of the key electrical, optical, and thermal parameters that define the performance range of LEDs.

2.1 Absolute Maximum Ratings

These ratings define the limits that may cause permanent damage to the device. Operation under these conditions is not guaranteed.

• Reverse Voltage (V_R):5V. Exceeding this voltage under reverse bias may cause immediate junction breakdown.
• Continuous Forward Current (I_F):25mA. The maximum DC current to ensure long-term reliable operation.
• Peak Forward Current (I_FP):60mA (duty cycle 1/10, frequency 1kHz). Suitable for pulse operation, not suitable for DC.
• Power consumption (P_d):60mW. The maximum power that the package can dissipate at ambient temperature Ta=25°C, limiting the combination of forward voltage and current.
• ESD Sensitivity (HBM):2000V. Inaonyesha kifaa kina uwezo wa kati wa kustahimili umeme wa tuli, lakini bado inahitaji hatua za kawaida za ulinzi dhidi ya ESD.
• Safu ya joto:Joto la kufanya kazi: -40°C hadi +85°C; Joto la kuhifadhi: -40°C hadi +90°C.
• Joto la kuchomelea:Withstand a reflow soldering profile with a peak temperature of 260°C for 10 seconds, or hand soldering at 350°C for 3 seconds per solder terminal.

2.2 Photoelectric Characteristics

At Ta=25°C and I_FMeasured under =20mA conditions, these are typical performance parameters.

• Luminous intensity (I_v):Ranges from 36.0 mcd (minimum) to 90.0 mcd (maximum), with a typical tolerance of ±11%. This defines the perceived brightness.
• Viewing angle (2θ_1/2):Kusanin kimanin 100 digiri (misali). Wannan fadi na kallo yana ba da kyakkyawan gani daga gefe.
• Kololuwar tsayin raɗaɗi (λ_p):650 nm (misali). Tsayin raɗaɗi mafi ƙarfi na fitarwa.
• Babban tsayin raɗaɗi (λ_d):Between 636.0 nm and 646.0 nm. This defines the perceived color (deep red).
• Spectral bandwidth (Δλ):Approximately 20 nm (typical). Indicates the spectral purity of the emitted light.
• Forward voltage (V_F):Between 1.70 V and 2.30 V at 20mA, with a typical tolerance of ±0.05V. This is crucial for the calculation of the current-limiting resistor.
• Reverse current (I_R):At V_R=5V, maximum 10 μA. This device is not suitable for reverse bias operation.

3. Binning System Description

Products are binned according to performance to ensure consistency within the same production lot. Part number 19-21/R8C-FN2Q1/3T includes these binning codes.

3.1 Luminous Intensity Binning

In I_FGrading at =20mA. The code "Q1" in the part number corresponds to the highest brightness grade.

• N2:36.0 – 45.0 mcd
• P1:45.0 – 57.0 mcd
• P2:57.0 – 72.0 mcd
• Q1:72.0 – 90.0 mcd

3.2 Dominant Wavelength Binning

In I_FBinning at =20mA. Code "FN2" is likely related to this chromaticity sorting.

• FF4:636.0 – 641.0 nm
• FF5:641.0 – 646.0 nm

3.3 Forward Voltage Binning

In I_F=20mA time grading. The code "19-21" in the part number indicates the voltage grading range.

• 19:1.70 – 1.80 V
• 20:1.80 – 1.90 V
• 21:1.90 – 2.00 V
• 22:2.00 – 2.10 V
• 23:2.10 – 2.20 V
• 24:2.20 – 2.30 V

4. Performance Curve Analysis

Although the provided text does not detail specific charts, typical curves for such devices include:

• Relative Luminous Intensity vs. Forward Current:How display brightness increases with current, typically growing sublinearly at higher currents due to heating.
• Forward Voltage vs. Forward Current:Demonstrates the exponential I-V characteristic of a diode.
• Relative Luminous Intensity vs. Ambient Temperature:The graph shows the decrease in light output with increasing junction temperature, a key consideration for thermal management.
• Spectral distribution:Relative intensity vs. wavelength plot, centered at 650nm with a bandwidth of approximately 20nm.

Designers should refer to these curves to understand performance under non-standard conditions (different current, temperature).

5. Mechanical and Packaging Information

5.1 Package Dimensions

The nominal dimensions of the 19-21 SMD package are 2.0mm (length) x 1.25mm (width) x 0.8mm (height). A clear cathode mark is indicated on the package to ensure correct orientation. All unspecified tolerances are ±0.1mm. An accurate dimensional drawing is essential for PCB pad layout design.

5.2 Polarity Identification

Correct polarity is crucial. The package has a clear cathode mark. Incorrect insertion will cause the LED to fail to illuminate, as it will be in a reverse-biased state.

6. Welding and Assembly Guide

6.1 Reflow soldering temperature profile

This LED is rated for lead-free reflow soldering. The recommended temperature profile includes:

• Preheat:150–200°C, for 60–120 seconds.
• Time above liquidus (217°C):60–150 seconds.
• Peak temperature:Maximum 260°C, hold time not exceeding 10 seconds.
• Heating/Cooling Rate:Above 255°C, maximum heating rate 6°C/sec, maximum cooling rate 3°C/sec.

Key Points:Reflow soldering should not exceed two times to avoid thermal stress damage.

6.2 Manual soldering

If manual soldering is necessary:

• 使用烙铁头温度 <350°C 的烙铁。
• 每个焊端的接触时间限制在 3 秒以内。Use a soldering iron with a power ≤25W.
• Allow at least 2 seconds between soldering each terminal.
• Avoid applying mechanical stress to the component during soldering.

6.3 Storage and Moisture Sensitivity

Components are packaged in moisture barrier bags with desiccant.

• Before use:Do not open the bag before preparing for assembly.
• After opening:Use within 168 hours (7 days) if stored at ≤30°C and ≤60% RH.
• Exposure Limit:If the exposure time is exceeded or the desiccant indicator shows saturation, baking at 60±5°C for 24 hours is required before reflow soldering to remove moisture.

7. Packaging and Ordering Information

7.1 Packaging Specifications

LEDs are supplied in carrier tape reels suitable for automated assembly.

• Carrier tape width: 8mm.
• Reel diameter:7 inches.
• Quantity per roll:3000 pieces.
• Moisture-proof bag:Contains desiccant and humidity indicator label.

7.2 Label Description

Reel label contains key information for traceability and verification:

• Customer Part Number (CPN)
• Part Number (P/N)
• Quantity (QTY)
• CAT
• HUE
• Forward Voltage Level (REF)
• Lot Number (LOT No.)

8. Application Design Considerations

8.1 Current Limiting Resistor Must Be Used

LED is a current-driven device.An external current-limiting resistor must always be connected in series.The forward voltage has a negative temperature coefficient; a small increase in voltage can lead to a large, potentially destructive increase in current if not properly limited. Use the formula R = (V_{Power Supply}- V_F) / I_F.

Calculate the resistance value.

8.2 Thermal Management

Although the package is small, the power consumption (up to 60mW) generates heat. For continuous operation in high current or high-temperature environments, ensure sufficient PCB copper foil area or thermal vias are used to conduct heat away from the LED pad to maintain a low junction temperature, thereby achieving optimal lifespan and light output stability.

8.3 Application Limitations

This product is designed for general commercial and industrial applications. It may not be suitable for high-reliability applications without prior certification. Such applications include, but are not limited to, automotive safety/security systems, military/aerospace, and life-critical medical equipment. The device must not be operated outside the conditions specified in this datasheet.

9. Technical Comparison and Differentiation

• The primary differentiation of this 19-21 Deep Red LED lies in the specific combination of its attributes:Compared to larger SMD LEDs (e.g., 3528):
• It offers a significantly smaller footprint for space-constrained designs, although the total light output is typically lower.Compared to standard red LEDs (e.g., 630nm):
• The 650nm deep red emission provides a unique color point, which may be desired for specific aesthetic or functional reasons (e.g., certain sensor applications, specific backlight color requirements).Compared to non-binned LEDs:

A comprehensive binning system (intensity, wavelength, voltage) ensures higher consistency in color and brightness within the same production batch, which is crucial for applications using multiple LEDs where uniformity is important.

10. Frequently Asked Questions (FAQs)

10.1 Why does my LED need a series resistor?

The I-V characteristic of an LED is very steep. Without a resistor to limit the current, any small variation in the supply voltage or forward voltage drop (which changes with temperature) can cause a large change in current, likely exceeding the absolute maximum rating and damaging the LED. The resistor provides a stable, predictable current._F?

10.2 Can I use a voltage higher than its VCan this voltage drive this LED?Yes, but_Fprovided you must use a series resistor

(or a constant current driver) to reduce the excess voltage and set the correct current. Due to device variations and temperature changes, directly applying a voltage equal to V

is impractical.

10.3 What happens if it is soldered in reverse?

LED will not light up because it will be in a reverse bias state. As long as the reverse voltage does not exceed the maximum rating of 5V, a brief incorrect insertion should not cause immediate damage. However, it will not function.

10.4 Why is there a 7-day time limit after opening the moisture-proof bag?

The plastic packaging of SMD components absorbs moisture from the air. During high-temperature reflow soldering, this trapped moisture rapidly expands, causing internal delamination or the "popcorn" effect, which can damage the LED chip or package. The 7-day floor life assumes proper storage conditions; exceeding this time requires baking to remove moisture.11. Practical Design and Usage Examples

1. Scenario:Design a status indicator panel using 10 uniform deep red LEDs, powered by a 5V digital logic power rail.
2. Current selection:Select the drive current. For good brightness and lifetime, it is specified as 20mA in the datasheet. Using 15mA will increase lifetime and reduce heat generation._FResistance calculation:_FAssuming worst-case V_F= 2.3V (maximum value in the datasheet). For a 5V power supply with I
3. =20mA: R = (5V - 2.3V) / 0.02A = 135 Ω. The closest standard values are 130 Ω or 150 Ω. Using 150 Ω yields I≈ (5-2.3)/150 = 18mA, which is safe and within the specification range.²Resistor power dissipation:²P = I
4. R = (0.018)* 150 = 0.0486W. A standard 1/8W (0.125W) resistor is sufficient.
5. PCB layout:Connect a 150Ω resistor in series with the anode of each LED. Design the pad layout according to the package size. Ensure the cathode marking on the PCB silkscreen matches the marking on the LED. For thermal performance, connect the LED pads to a small copper pour.

Assembly:

Keep the reel sealed until the production line is ready. Precisely follow the reflow soldering temperature profile. After assembly, avoid bending the PCB near the LEDs._F12. Working Principle

This LED is based on an AlGaInP (aluminum gallium indium phosphide) semiconductor chip. When a forward voltage exceeding the diode junction potential (V

) is applied, electrons and holes are injected into the active region where they recombine. In this specific material system, the energy released during recombination corresponds to photons in the deep red portion of the visible spectrum (approximately 650nm). The epoxy encapsulation is water-clear to maximize light extraction efficiency and also serves to protect the semiconductor chip from environmental influences.

• 13. Technical Trends19-21 Paketleme, fotonikte küçülme ve entegrasyon yönündeki süregelen eğilimi temsil eder. Günümüzde mevcut en küçük paketleme olmasa da, boyut, üretilebilirlik ve performans arasında bir denge sağlar. Gösterge tipi LED'lerde endüstri trendi şu alanlara odaklanmaya devam etmektedir:
• Verimliliği Artırma:Daha düşük sürücü akımında daha yüksek ışık şiddeti (mcd) elde ederek sistem güç tüketimini azaltmak.
• Enhancing reliability:Improving materials and packaging to withstand higher reflow soldering temperatures and harsher environmental conditions.
• Finer binning:Provide more precise color and intensity sorting to meet the application requirements that demand high uniformity, such as full-color displays or backlight arrays.