XI5050U/LKE-HXXXXX260Z18/2N SMD High Power LED Datasheet - 5.0x5.0mm Package - 26V Max - 180mA - White Light - English Technical Document

1. Product Overview

The XI5050U/LKE-HXXXXX260Z18/2N is a lighting-grade, high-power LED housed in a compact 5050 surface-mount device (SMD) package. This component is engineered to deliver high luminous output and efficiency, making it suitable for a broad range of general and specialized illumination applications. Its top-view white light emission and robust construction align with modern manufacturing and environmental standards.

1.1 Core Advantages and Positioning

This LED distinguishes itself through a combination of high luminous intensity and a wide 120-degree viewing angle, ensuring broad and uniform light distribution. It is compliant with key industry standards including RoHS, EU REACH, and halogen-free requirements (Br<900ppm, Cl<900ppm, Br+Cl<1500ppm), making it suitable for global markets with stringent environmental regulations. The Pb-free construction further enhances its environmental profile.

1.2 Target Applications

The primary application domains for this LED include:

• Decorative and Entertainment Lighting: Ideal for accent lighting, architectural highlights, and stage lighting due to its brightness and color consistency.
• Agriculture Lighting: Suitable for horticultural lighting systems where specific light spectra and high efficiency are required for plant growth.
• General Illumination: A reliable choice for residential, commercial, and industrial lighting fixtures such as downlights, panel lights, and streetlights.

2. In-Depth Technical Parameter Analysis

This section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters specified in the datasheet.

2.1 Absolute Maximum Ratings

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

• Forward Current (I_F): 200 mA (DC). This is the maximum continuous current the LED can handle.
• Pulse Forward Current (I_PF): 280 mA. A higher current allowed for short pulse operation, useful for testing or specific driving schemes.
• Power Dissipation (P_d): 5.2 W. The maximum power the package can dissipate as heat, calculated typically as V_F * I_F.
• Junction Temperature (T_j): 125 °C. The maximum allowable temperature at the semiconductor junction.
• Thermal Resistance, Junction to Board (R_θjc): 10 °C/W. This critical parameter indicates how effectively heat flows from the LED junction to the circuit board. A lower value signifies better thermal performance.
• Soldering Temperature: Reflow: 260°C for 10 seconds; Hand soldering: 350°C for 3 seconds. Adherence to these profiles is crucial to prevent package or die damage.

2.2 Electro-Optical Characteristics

These are the typical performance parameters measured under standard test conditions (T_soldering = 25°C, I_F = 180mA).

• Luminous Flux (Φ): Minimum values range from 700 lm to 780 lm depending on the correlated color temperature (CCT) variant, with a tolerance of ±11%. This defines the total visible light output.
• Forward Voltage (V_F): Maximum of 26 V at 180mA, with a tolerance of ±0.1V. The high V_F suggests this is a multi-chip LED array within the package, connected in series.
• Color Rendering Index (CRI or R_a): Minimum of 70 for the listed variants, with a tolerance of ±2. CRI measures the light source's ability to reveal the true colors of objects compared to a natural light source.
• Viewing Angle (2θ_1/2): 120 degrees. The angle at which luminous intensity is half of the value at 0 degrees (on-axis).
• Reverse Current (I_R): Maximum 50 µA at V_R = 5V. LEDs are not designed for reverse bias; this parameter indicates leakage.

3. Binning System Explanation

The product uses a comprehensive binning system to ensure color and brightness consistency, which is vital for lighting applications where multiple LEDs are used together.

3.1 Color Rendering Index (CRI) Binning

The datasheet defines CRI bins with specific minimum values, denoted by a single letter in the part number. For example, 'L' corresponds to a minimum CRI of 70. Higher bins like 'H' (90 min) and 'R' (90 min with R9 > 50) offer superior color fidelity, important for retail or museum lighting.

3.2 Luminous Flux Binning

Flux is binned in 50-lumen steps, specific to each CCT group. For instance, a 4000K LED might be binned as 780L50 (780-830 lm), 830L50 (830-880 lm), etc. This allows designers to select LEDs for precise lumen output requirements, ensuring uniformity across a fixture.

3.3 Forward Voltage Binning

Voltage is grouped from 22V to 26V in 1V steps (22J, 23J, 24J, 25J). Matching V_F bins can simplify driver design and improve current matching in parallel strings.

3.4 Chromaticity Coordinate Binning

The datasheet provides detailed (x, y) coordinate boxes on the CIE 1931 diagram for each CCT (2700K, 3000K, 3500K, 4000K, 5000K, 5700K, 6500K). Each CCT has multiple sub-bins (e.g., 27K-A, 27K-B, 27K-F, 27K-G) that define smaller regions within the standard ANSI quadrangles. This tight binning is crucial for achieving excellent color uniformity, eliminating visible differences between adjacent LEDs.

4. Mass Production List & Ordering Information

The available standard products are listed with their key parameters. The part number follows the structure: XI5050U/LKE-H[FluxBin][CCT][VoltageIndex][CurrentIndex]/[Configuration].

Example: XI5050U/LKE-H50780260Z18/2N decodes as:

- Flux Bin: 780 lm (Min) for 5000K

- CCT: 5000K

- V_F Index: '260' for 26V max

- I_F Index: 'Z18' for 180mA

- Configuration: /2N (likely indicating a 2-chip or other internal configuration).

Standard offerings include CCTs from 2700K (Warm White) to 6500K (Cool White), all with a minimum CRI of 70 and V_Fmax of 26V.

5. Performance and Application Considerations

5.1 Thermal Management

With a power dissipation up to 5.2W and an R_θjc of 10°C/W, effective thermal management is non-negotiable. The LED must be mounted on a PCB with adequate thermal vias and, in most cases, attached to a heatsink. Exceeding the junction temperature (T_j) of 125°C will drastically reduce lifetime and luminous output. Designers should calculate the expected T_j using the formula: T_j = T_board + (P_d * R_θjc).

5.2 Electrical Drive Considerations

The LED is specified at a forward current of 180mA. It must be driven by a constant-current source, not a constant-voltage source, to ensure stable light output and prevent thermal runaway. The high forward voltage (up to 26V) requires a driver capable of delivering this voltage. For designs using multiple LEDs, series connection will sum the V_F, while parallel connection requires careful bin matching or individual current regulation to prevent current hogging.

5.3 Optical Design

The 120-degree viewing angle provides a wide, Lambertian-like emission pattern. For applications requiring a narrower beam, secondary optics (lenses or reflectors) will be necessary. The water-clear resin ensures high light extraction efficiency.

6. Soldering and Handling Guidelines

• ESD Sensitivity: The device is sensitive to electrostatic discharge (ESD). Proper ESD precautions (grounded workstations, wrist straps) must be observed during handling and assembly.
• Reflow Soldering: Follow the recommended profile: peak temperature of 260°C for a maximum of 10 seconds. A standard lead-free reflow profile is applicable.
• Hand Soldering: If necessary, limit iron contact to 350°C for a maximum of 3 seconds per pad.
• Storage: Store in conditions between -35°C and +100°C, preferably in moisture-barrier bags if the humidity is high.

7. Frequently Asked Questions (FAQs)

7.1 Why is the forward voltage so high (26V)?

The 5050 package likely contains multiple LED chips connected in series internally. The sum of the forward voltages of these individual chips results in the high package V_F. This design can simplify driver design in some high-voltage applications.

7.2 Can I drive this LED at a current higher than 180mA?

The absolute maximum rating for continuous current is 200mA. While driving at up to 200mA is permissible from a reliability standpoint, it will generate more heat and reduce the LED's lifetime. The photometric data (flux, CCT, CRI) is guaranteed at 180mA; performance at other currents may vary and should be characterized.

7.3 How do I achieve the best color uniformity in my fixture?

Select LEDs from the same tight chromaticity bin (e.g., all from 30K-F bin) and, if possible, the same flux bin. Work with your supplier to request matched bins for your production run.

7.4 What is the typical lifetime of this LED?

While the datasheet does not specify an L70 or L50 lifetime, the lifetime of an LED is primarily a function of junction temperature. Operating the LED at or below its recommended current (180mA) and maintaining a low junction temperature (well below 125°C) through good thermal design will maximize operational lifetime, typically reaching tens of thousands of hours.

8. Design Case Study: A Linear LED Fixture

Scenario: Designing a 4-foot linear fixture for office general illumination targeting 4000K color temperature and high uniformity.

Selection: Choose the XI5050U/LKE-H40780260Z18/2N variant (4000K, 780 lm min). Specify a single, tight chromaticity bin (e.g., 40K-F) and a single flux bin (e.g., 830L50) from the supplier.

Thermal Design: Mount the LEDs on a metal-core PCB (MCPCB) with a 2 oz copper layer. The MCPCB is then attached to an aluminum extrusion acting as a heatsink. Thermal simulations should confirm T_j remains below 100°C in the target ambient temperature.

Electrical Design: For a fixture with 20 LEDs, connect them all in series. The total V_F could be up to 520V (20 * 26V), requiring a constant-current driver with a compatible high-voltage output. Driving at the recommended 180mA ensures rated light output and longevity.

Optical Design: Use a milky white polycarbonate diffuser over the LEDs to blend the individual points into a smooth, uniform line of light, leveraging the native 120° beam angle.

9. Technology and Market Context

9.1 Operating Principle

This is a solid-state light source based on semiconductor physics. When a forward voltage is applied across the p-n junction of the LED chip(s), electrons and holes recombine, releasing energy in the form of photons (light). The specific materials (InGaN for white LEDs) and phosphor coatings determine the wavelength and color of the emitted light.

9.2 Comparison and Trends

The 5050 high-power package represents a mature platform offering a balance of cost, performance, and reliability. Compared to smaller packages (e.g., 2835), it typically offers higher total flux per device. The market trend continues towards higher efficacy (lumens per watt), improved color quality (higher CRI and R9), and tighter binning for superior uniformity. This product, with its defined high-CRI options and detailed chromaticity bins, addresses these evolving market demands for quality lighting.