SMD LED 19-21/R6C-AL2N1VY/3T Datasheet - Size 2.0x1.25x0.8mm - Voltage 1.7-2.2V - Brilliant Red - English Technical Documentation

1. Product Overview

The 19-21/R6C-AL2N1VY/3T is a surface-mount device (SMD) LED utilizing AlGaInP chip technology to produce a brilliant red light output. This component is designed for high-density PCB applications where space and weight are critical constraints. Its compact 2.0mm x 1.25mm x 0.8mm footprint enables significant miniaturization of end products, reducing required board space and overall equipment size. The device is packaged on 8mm tape supplied on 7-inch diameter reels, making it fully compatible with standard automated pick-and-place assembly equipment. It is a mono-color, lead-free (Pb-free) component that complies with RoHS, EU REACH, and halogen-free regulations (Br <900 ppm, Cl <900 ppm, Br+Cl < 1500 ppm), ensuring its suitability for modern, environmentally conscious electronics manufacturing.

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

Operating the device beyond these limits may cause permanent damage. The absolute maximum ratings are specified at an ambient temperature (Ta) of 25°C. The maximum reverse voltage (VR) is 5V, emphasizing that this LED is not designed for reverse-bias operation. The continuous forward current (IF) rating is 25 mA, with a permissible peak forward current (IFP) of 60 mA under pulsed conditions (duty cycle 1/10 at 1 kHz). The maximum power dissipation (Pd) is 60 mW. The device can withstand an electrostatic discharge (ESD) of 2000V per the Human Body Model (HBM). The operational temperature range is from -40°C to +85°C, and the storage temperature range is from -40°C to +90°C. Soldering temperature limits are defined for two processes: reflow soldering at a peak of 260°C for a maximum of 10 seconds, and hand soldering at a maximum of 350°C for 3 seconds per terminal.

2.2 Electro-Optical Characteristics

The key performance parameters are measured at a standard test current of 5mA and Ta=25°C. The luminous intensity (Iv) has a typical range, with minimum and maximum values defined by the binning system. The viewing angle (2θ1/2) is typically 100 degrees, providing a wide emission pattern. The peak wavelength (λp) is approximately 632 nm, and the dominant wavelength (λd) ranges from 617.5 nm to 633.5 nm, corresponding to a brilliant red color. The spectral bandwidth (Δλ) is typically 20 nm. The forward voltage (VF) ranges from 1.70V to 2.20V at 5mA. The reverse current (IR) is guaranteed to be 10 μA or less at the maximum reverse voltage of 5V. Important notes specify tolerances: ±11% for luminous intensity, ±1nm for dominant wavelength, and ±0.05V for forward voltage.

3. Binning System Explanation

To ensure color and brightness consistency in production, the LEDs are sorted into bins based on three key parameters.

3.1 Luminous Intensity Binning

LEDs are categorized into four bins (L2, M1, M2, N1) based on their measured luminous intensity at IF=5mA. The bins define minimum and maximum intensity ranges: L2 (14.5-18.0 mcd), M1 (18.0-22.5 mcd), M2 (22.5-28.5 mcd), and N1 (28.5-36.0 mcd). This allows designers to select components that meet specific brightness requirements for their application.

3.2 Dominant Wavelength Binning

The color (hue) is controlled through dominant wavelength binning. Four bins (E4, E5, E6, E7) are defined: E4 (617.5-621.5 nm), E5 (621.5-625.5 nm), E6 (625.5-629.5 nm), and E7 (629.5-633.5 nm). This tight control ensures visual color uniformity across multiple LEDs used in an array or backlighting application.

3.3 Forward Voltage Binning

Forward voltage is binned to aid in circuit design, particularly for current-limiting resistor calculation and power supply design. Five bins (19, 20, 21, 22, 23) are offered, each covering a 0.1V range from 1.70V to 2.20V at IF=5mA.

4. Performance Curve Analysis

The datasheet references typical electro-optical characteristic curves. While the specific graphs are not detailed in the provided text, such curves typically illustrate the relationship between forward current and luminous intensity, forward voltage versus temperature, and the relative spectral power distribution. These curves are essential for designers to understand how the LED's performance changes under different operating conditions, such as varying drive current or ambient temperature, allowing for optimized and reliable circuit design.

5. Mechanical and Package Information

5.1 Package Dimensions

The 19-21 SMD LED has a compact package measuring 2.0mm in length, 1.25mm in width, and 0.8mm in height. The dimensional drawing specifies the location of the cathode mark, which is crucial for correct orientation during assembly. All unspecified tolerances are ±0.1mm.

5.2 Polarity Identification

A clear cathode mark is indicated on the package. Correct polarity must be observed during placement and soldering to ensure proper function and prevent damage.

6. Soldering and Assembly Guidelines

6.1 Storage and Handling

The LEDs are packaged in moisture-resistant barrier bags with desiccant. The bag must not be opened until the components are ready for use. Before opening, storage conditions should be 30°C or less and 60% relative humidity or less. Once opened, the LEDs must be used within 168 hours (7 days). Any unused components should be resealed in a moisture-proof package. If the storage time is exceeded or the desiccant indicator shows moisture absorption, a baking treatment at 60 ±5°C for 24 hours is required before use to prevent "popcorning" during reflow soldering.

6.2 Reflow Soldering Profile

A lead-free (Pb-free) reflow soldering profile is specified. Key parameters include: a pre-heating zone between 150-200°C for 60-120 seconds, a time above liquidus (217°C) of 60-150 seconds, a peak temperature not exceeding 260°C held for a maximum of 10 seconds, and controlled heating and cooling rates (max 6°C/sec and 3°C/sec, respectively). Reflow soldering should not be performed more than two times. Stress should not be applied to the LED during heating, and the PCB should not be warped after soldering.

6.3 Hand Soldering and Rework

For hand soldering, a soldering iron with a tip temperature below 350°C and a power rating below 25W should be used. Contact time per terminal must not exceed 3 seconds. A minimum interval of 2 seconds should be left between soldering each terminal. Repair after soldering is discouraged. If unavoidable, a double-head soldering iron should be used to simultaneously heat both terminals, and the potential for damage must be assessed beforehand.

7. Packaging and Ordering Information

7.1 Reel and Tape Specifications

The components are supplied in carrier tape on 7-inch diameter reels. Each reel contains 3000 pieces. Detailed dimensions for the reel and the carrier tape pockets are provided, with standard tolerances of ±0.1mm unless otherwise noted.

7.2 Label Explanation

The reel label contains key information: Customer's Product Number (CPN), Product Number (P/N), Packing Quantity (QTY), Luminous Intensity Rank (CAT), Chromaticity Coordinates & Dominant Wavelength Rank (HUE), Forward Voltage Rank (REF), and Lot Number (LOT No). This data is critical for traceability and ensuring the correct component bin is used in production.

8. Application Recommendations

8.1 Typical Application Scenarios

This LED is well-suited for a variety of indicator and backlighting applications due to its small size, reliability, and bright red output. Common uses include backlighting for instrument panel dashboards and switches, status indicators and keypad backlighting in telecommunication devices (phones, fax machines), flat backlighting for LCDs, switch illumination, and general-purpose indicator applications.

8.2 Critical Design Considerations

Current Limiting: An external current-limiting resistor is mandatory. The LED is a current-driven device, and even a small increase in forward voltage can cause a large, potentially destructive increase in current. The resistor value must be calculated based on the supply voltage, the LED's forward voltage (considering the voltage bin), and the desired operating current (not to exceed 25 mA continuous).
Thermal Management: While the power dissipation is low, ensuring the LED operates within its specified temperature range is vital for long-term reliability. Adequate PCB copper area and ventilation should be considered in high-density or high-ambient-temperature designs.
ESD Protection: Although rated for 2000V HBM, standard ESD handling precautions should be followed during assembly and handling.

9. Technical Comparison and Differentiation

The primary advantage of the 19-21 package compared to larger lead-frame type LEDs is its significantly reduced footprint and height, enabling higher packing density on PCBs and ultimately smaller end products. The use of AlGaInP technology provides high efficiency and a saturated brilliant red color. Compliance with modern environmental standards (RoHS, REACH, Halogen-Free) is a key differentiator, making it suitable for global markets with strict regulatory requirements. Its compatibility with standard infrared and vapor phase reflow processes aligns it with mainstream SMT assembly lines.

10. Frequently Asked Questions (FAQ)

Q: Can I drive this LED without a series resistor?
A: No. The LED must be driven with a constant current source or, more commonly, a voltage source in series with a current-limiting resistor. Operating it directly from a voltage source will result in uncontrolled current flow, leading to immediate failure.

Q: What is the difference between peak wavelength and dominant wavelength?
A: Peak wavelength (λp) is the wavelength at which the emitted optical power is maximum. Dominant wavelength (λd) is the single wavelength of monochromatic light that matches the perceived color of the LED. λd is more relevant for color specification in visual applications.

Q: How do I interpret the bin codes (e.g., R6C-AL2N1VY)?
A: The full part number 19-21/R6C-AL2N1VY/3T encodes package type, chip technology, and performance bins. While the exact decoding may be proprietary, the 'N1' typically corresponds to the luminous intensity bin, and other characters relate to the wavelength and voltage bins specified in the datasheet tables.

Q: Why is the storage time after opening the bag limited to 7 days?
A: The plastic packaging of SMD components can absorb moisture from the air. During the high heat of reflow soldering, this trapped moisture can vaporize rapidly, causing internal delamination or cracking ("popcorning"). The 7-day floor life is the period during which moisture absorption remains below a critical level for a single reflow pass.

11. Practical Design and Usage Case

Consider designing a compact status indicator panel for industrial equipment. The panel requires multiple bright red LEDs spaced closely together. The 19-21 LED's small 2.0x1.25mm footprint allows for a high-density layout on a limited PCB area. By specifying LEDs from the same luminous intensity bin (e.g., N1) and dominant wavelength bin (e.g., E6), the designer can ensure uniform brightness and color across all indicators, providing a consistent and professional user interface. The wide 100-degree viewing angle ensures the indicator is visible from various angles. The component's compatibility with automated assembly reduces manufacturing cost and improves reliability compared to hand-soldered alternatives.

12. Operating Principle Introduction

This LED is based on a semiconductor chip made from Aluminum Gallium Indium Phosphide (AlGaInP). When a forward voltage exceeding the device's threshold is applied, electrons and holes are injected into the active region of the semiconductor. These charge carriers recombine, releasing energy in the form of photons (light). The specific composition of the AlGaInP layers determines the bandgap energy of the semiconductor, which directly dictates the wavelength (color) of the emitted light—in this case, brilliant red. The light is emitted through the top surface of the chip, which is encapsulated in a clear epoxy resin that also provides mechanical protection and helps shape the light output pattern.

13. Technology Trends and Context

The 19-21 SMD LED represents a mature and reliable packaging technology within the broader trend of electronics miniaturization. The ongoing development in LED technology focuses on increasing luminous efficacy (more light output per electrical watt), improving color rendering, and enabling even smaller package sizes. While newer package types like chip-scale packages (CSP) offer further size reductions, the 19-21 remains a cost-effective and widely supported workhorse for standard indicator applications. The emphasis on halogen-free and REACH-compliant materials reflects the industry-wide shift towards more sustainable and environmentally friendly manufacturing processes. The specified compatibility with lead-free, high-temperature reflow profiles aligns with the global transition away from lead-based solders.