SMD LED 19-219/T3D-AQ2R2TY/3T Datasheet - Size 1.6x0.8x0.77mm - Voltage 2.6-3.0V - Power 95mW - Pure White - English Technical Document

1. Product Overview

The 19-219/T3D-AQ2R2TY/3T is a compact, surface-mount device (SMD) LED designed for modern electronic applications requiring reliable indicator lighting and backlighting. This mono-color LED emits a pure white light, achieved through an InGaN chip encapsulated in a yellow diffused resin. Its primary advantages include a significantly reduced footprint compared to traditional lead-frame LEDs, enabling higher packing density on PCBs, reduced storage requirements, and ultimately contributing to the miniaturization of end equipment. The component is also Pb-free and compliant with RoHS directives, making it suitable for environmentally conscious designs.

1.1 Core Features and Advantages

• Miniaturized Package: The small form factor (1.6mm x 0.8mm) allows for dense board layouts and smaller end products.
• Automation Compatibility: Supplied on 8mm tape on 7-inch reels, it is fully compatible with standard automatic pick-and-place assembly equipment.
• Robust Soldering: Compatible with both infrared and vapor phase reflow soldering processes, ensuring reliable manufacturing.
• Environmental Compliance: The product is Pb-free and maintains compliance with RoHS regulations.
• Lightweight: Ideal for portable and miniature applications where weight is a critical factor.

1.2 Target Applications

This LED is versatile and finds use in several key areas:

• Telecommunications: Used as status indicators and backlighting for keys and displays in telephones and fax machines.
• Display Backlighting: Suitable for flat backlighting of LCD panels, as well as backlighting switches and symbols.
• General Purpose Indication: Can be used in a wide array of consumer electronics, industrial controls, and automotive interiors where a compact white light source is needed.

2. Technical Specifications Deep Dive

This section provides a detailed analysis of the LED's absolute maximum ratings and key operational parameters. Adherence to these limits is crucial for ensuring long-term reliability and preventing device failure.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. Operation at or near these limits is not recommended.

• Reverse Voltage (V_R): 5V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (I_F): 25mA. The maximum DC current for continuous operation.
• Peak Forward Current (I_FP): 100mA (at 1/10 duty cycle, 1kHz). This allows for brief pulses of higher current, useful for multiplexing or pulsed operation.
• Power Dissipation (P_d): 95mW. The maximum power the package can dissipate, calculated as V_F * I_F.
• Electrostatic Discharge (ESD): 150V (Human Body Model). Proper ESD handling procedures must be followed during assembly and handling.
• Operating Temperature (T_opr): -40°C to +85°C. The ambient temperature range for reliable operation.
• Storage Temperature (T_stg): -40°C to +90°C.
• Soldering Temperature: Reflow: 260°C max for 10 seconds. Hand soldering: 350°C max for 3 seconds per terminal.

2.2 Electro-Optical Characteristics

These are the typical performance parameters measured at an ambient temperature (T_a) of 25°C. Designers should use the typical (Typ.) values for initial calculations but design to accommodate the min/max ranges.

• Luminous Intensity (I_v): 90.0 - 180 mcd (minimum to maximum, binned). Measured at a forward current (I_F) of 5mA. The wide range is managed through a binning system detailed later.
• Viewing Angle (2θ_1/2): 130 degrees (typical). This wide viewing angle makes it suitable for applications requiring broad illumination or visibility from multiple angles.
• Forward Voltage (V_F): 2.6V - 3.0V (at I_F=5mA). This parameter is also binned. A current-limiting resistor must be used in series with the LED to set the operating current based on the supply voltage and the V_F range.
• Reverse Current (I_R): 50 µA maximum (at V_R=5V). This indicates the level of leakage current when the device is reverse-biased.

3. Binning System Explanation

To ensure consistency in brightness and color in production, LEDs are sorted into bins based on measured performance. The 19-219 LED uses three distinct binning criteria.

3.1 Luminous Intensity Binning

LEDs are categorized into bins (Q1, R1, R2) based on their measured luminous intensity at 5mA. This allows designers to select a brightness grade suitable for their application, ensuring uniform appearance in multi-LED designs.

• Bin Q1: 90.0 - 112 mcd
• Bin R1: 112 - 140 mcd
• Bin R2: 140 - 180 mcd

3.2 Forward Voltage Binning

LEDs are also binned by their forward voltage drop (V_F) at 5mA. Matching V_F bins can help achieve more uniform current sharing when LEDs are connected in parallel.

• Bin 28: 2.6V - 2.7V
• Bin 29: 2.7V - 2.8V
• Bin 30: 2.8V - 2.9V
• Bin 31: 2.9V - 3.0V

3.3 Chromaticity Coordinate Binning

For white LEDs, color consistency is critical. The products are graded into six bins (1-6) based on their CIE 1931 (x, y) chromaticity coordinates, measured at I_F=5mA. Each bin defines a quadrilateral area on the CIE chart. The specification calls for a tolerance of ±0.01 in the coordinates. Selecting LEDs from the same chromaticity bin is essential for applications where color matching is important.

4. Performance Curve Analysis

The datasheet provides several characteristic curves that illustrate the LED's behavior under varying conditions. Understanding these curves is key to optimal circuit design.

4.1 Forward Current vs. Forward Voltage (I-V Curve)

This curve shows the non-linear relationship between current and voltage. The forward voltage increases with current. The curve is essential for selecting the appropriate current-limiting resistor value. A small change in voltage can lead to a large change in current, highlighting the necessity of current regulation.

4.2 Luminous Intensity vs. Forward Current

This graph demonstrates that light output is approximately proportional to forward current within the operating range. However, efficiency may drop at very high currents due to increased heat.

4.3 Luminous Intensity vs. Ambient Temperature

LED light output decreases as the junction temperature rises. This curve quantifies that derating. For high-temperature environments or high-power operation, thermal management must be considered to maintain brightness.

4.4 Forward Current Derating Curve

This curve defines the maximum allowable continuous forward current as a function of ambient temperature. As temperature increases, the maximum current must be reduced to prevent exceeding the device's power dissipation limit and to ensure reliability.

4.5 Spectrum Distribution

The spectral output curve shows the relative intensity across wavelengths for this white LED. It typically features a blue peak from the InGaN chip and a broader yellow emission from the phosphor, combining to produce white light.

4.6 Radiation Diagram

This polar plot visually represents the spatial distribution of light (viewing angle pattern), confirming the 130-degree typical viewing angle.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED has a compact footprint of 1.6mm (length) x 0.8mm (width) with a typical height of 0.77mm. Critical dimensions include the pad spacing and size. A recommended solder pad layout is provided to ensure a reliable solder joint and proper alignment during reflow. The cathode is identified by a specific pad marking or a chamfered corner on the package bottom view.

5.2 Polarity Identification

Correct polarity is vital. The cathode pad is distinctly marked in the package drawing. On the carrier tape, the polarity orientation is also indicated to guide automated assembly equipment.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

For Pb-free soldering, a specific temperature profile must be followed:

• Pre-heating: 150-200°C for 60-120 seconds.
• Time Above Liquidus (217°C): 60-150 seconds.
• Peak Temperature: 260°C maximum, held for no more than 10 seconds.
• Heating/Cooling Rate: Maximum 3°C/sec up to 255°C, and 6°C/sec maximum overall.

Reflow soldering should not be performed more than two times on the same LED.

6.2 Hand Soldering

If hand soldering is necessary, extreme care is required. Use a soldering iron with a tip temperature below 350°C, applying heat to each terminal for no more than 3 seconds. The soldering iron power should be 25W or less. Allow an interval of at least 2 seconds between soldering each terminal to prevent thermal shock.

6.3 Storage and Moisture Sensitivity

The LEDs are packaged in a moisture-resistant bag with desiccant.

• Before Opening: Store at ≤30°C and ≤90% Relative Humidity (RH).
• After Opening (Floor Life): 1 year at ≤30°C and ≤60% RH. Unused parts should be resealed.
• Baking: If the desiccant indicator changes or storage time is exceeded, bake at 60±5°C for 24 hours before use in a reflow process.

6.4 Critical Precautions

• Current Limiting: An external series resistor is mandatory. Without it, minor supply voltage fluctuations can cause large, destructive current surges.
• Mechanical Stress: Avoid applying stress to the LED body during soldering or in the final application. Do not warp the PCB after assembly.
• Repairing: Repair after soldering is strongly discouraged. If unavoidable, a specialized double-head soldering iron must be used to simultaneously heat both terminals, preventing mechanical stress from thermal expansion mismatch.

7. Packaging and Ordering Information

7.1 Reel and Tape Specifications

The components are supplied on 8mm wide carrier tape wound on a standard 7-inch diameter reel. Each reel contains 3000 pieces. Detailed reel and carrier tape dimensions are provided for compatibility with automated assembly equipment.

7.2 Label Explanation

The reel label contains several codes:

• P/N: Product Number (e.g., 19-219/T3D-AQ2R2TY/3T).
• CAT: Luminous Intensity Rank (e.g., Q1, R1, R2).
• HUE: Chromaticity Coordinates & Dominant Wavelength Rank (e.g., 1-6).
• REF: Forward Voltage Rank (e.g., 28-31).
• LOT No: Traceable manufacturing lot number.

These codes allow precise identification and traceability of the product's performance characteristics.

8. Application Design Considerations

8.1 Circuit Design

The most critical aspect of driving this LED is current regulation. A simple series resistor is sufficient for many applications. The resistor value (R_s) can be calculated using Ohm's Law: R_s = (V_supply - V_F) / I_F. Always use the maximum V_F from the bin range to ensure the current does not exceed the desired I_F when V_supply is at its maximum. For stability over temperature or with a variable supply voltage, consider using a constant current driver.

8.2 Thermal Management

While the power dissipation is low, in high ambient temperatures or enclosed spaces, the junction temperature can rise, reducing light output and lifespan. Ensure adequate airflow or thermal relief in the PCB layout, especially if multiple LEDs are used closely together.

8.3 Optical Design

The 130-degree viewing angle provides wide, diffuse illumination. For applications requiring a more focused beam, secondary optics (lenses) would be required. The yellow diffused resin helps in achieving a uniform luminous appearance.

9. Technical Comparison and Positioning

The 19-219 LED fits into a category of ultra-miniature SMD LEDs. Its key differentiator is its very small 1.6mm x 0.8mm footprint, which is smaller than common packages like 0603 (1.6mm x 0.8mm is similar in area but often in a different form factor) or 0805. This makes it ideal for space-constrained applications where every square millimeter counts. Compared to larger PLCC or through-hole LEDs, it offers vastly superior packing density and is essential for modern automated assembly. The pure white color, achieved through a blue chip and yellow phosphor, offers a neutral to cool white point suitable for indicator and backlight use.

10. Frequently Asked Questions (FAQ)

10.1 Why is a current-limiting resistor absolutely necessary?

LEDs are diodes with a very steep I-V curve in the forward region. A small increase in voltage beyond the nominal V_F causes a disproportionately large increase in current, which can instantly destroy the device due to overheating. The resistor provides a linear, predictable voltage drop that stabilizes the current.

10.2 Can I drive this LED with a 5V supply?

Yes, but you must use a series resistor. For example, to achieve I_F=20mA with a V_F of 3.0V (max), the resistor value would be R = (5V - 3.0V) / 0.020A = 100 Ohms. The power dissipated in the resistor would be P = I²R = (0.02^2)*100 = 0.04W, so a standard 1/8W or 1/10W resistor is adequate.

10.3 What do the bin codes mean for my design?

If your design uses multiple LEDs and requires uniform brightness, you should specify LEDs from the same luminous intensity bin (CAT) and chromaticity bin (HUE). If you are driving LEDs in parallel, using the same forward voltage bin (REF) can help achieve more balanced current sharing, though individual resistors per LED are still the most reliable method.

10.4 How sensitive is this LED to ESD?

With an ESD rating of 150V (HBM), it has moderate sensitivity. Standard ESD precautions should be observed during handling: use grounded workstations, wrist straps, and conductive containers. The automated tape-and-reel packaging helps minimize human handling.

11. Design and Usage Case Study

11.1 Case Study: Multi-LED Status Indicator Panel

Imagine designing a compact control panel with 12 white status indicators. Using the 19-219 LED allows them to be placed on a very tight pitch. To ensure uniform appearance, the designer specifies all LEDs from Bin R1 (112-140 mcd) and Hue Bin 3. Each LED is driven by a 5V rail through a 150-ohm series resistor, setting the current to approximately 13mA (assuming V_F ~ 3.0V), which is well within the 25mA limit and provides ample brightness while maximizing longevity. The PCB layout includes the recommended solder pad geometry and provides small thermal relief connections to the pads to facilitate soldering while maintaining a good thermal path.

12. Technology Principle Introduction

This white LED is based on a semiconductor principle called electroluminescence. The core is an indium gallium nitride (InGaN) chip that emits blue light when a forward current is applied across its p-n junction. This blue light then strikes a layer of yellow phosphor (ceramic particles) embedded in the encapsulating epoxy resin. The phosphor absorbs a portion of the blue light and re-emits it as yellow light. The combination of the remaining blue light and the converted yellow light is perceived by the human eye as white light. The specific ratios of the chip's emission and the phosphor's conversion efficiency determine the exact color temperature (warm, neutral, cool) and chromaticity coordinates of the white light produced.

13. Industry Trends and Development

The trend in indicator and backlight LEDs continues strongly toward miniaturization, higher efficiency, and improved color consistency. Packages like the 19-219 represent the ongoing effort to reduce size while maintaining or improving optical performance. Furthermore, there is a continuous drive for higher reliability under wider temperature ranges and harsher environmental conditions to meet automotive and industrial standards. The move to Pb-free and RoHS-compliant materials is now standard. Future developments may include even smaller form factors, integrated driver circuitry within the package, and LEDs with tunable color temperatures for smart lighting applications, though for simple indicator roles, the core technology of a blue chip + phosphor remains dominant due to its cost-effectiveness and reliability.