ELCH08 LED Datasheet - High Efficiency White LED - 290lm @ 1A - 2.85-3.9V - 120° Viewing Angle - English Technical Document

1. Product Overview

This document details the specifications for a high-efficiency white light-emitting diode (LED) component. The device is characterized by its compact package design, which delivers high luminous output, making it suitable for space-constrained applications requiring bright illumination. Its core advantages include a typical luminous flux of 290 lumens at a drive current of 1 Ampere, corresponding to an optical efficiency of approximately 87 lumens per watt. The LED incorporates robust ESD protection, enhancing its reliability in handling and assembly. It is fully compliant with RoHS directives and is manufactured using lead-free processes.

1.1 Target Applications

The LED is designed for a broad range of illumination purposes. Primary applications include serving as a camera flash or strobe light source in mobile devices and digital video equipment. It is also well-suited for general indoor lighting, backlighting for TFT displays, and various decorative or entertainment lighting systems. Furthermore, it finds use in automotive lighting for both interior and exterior functions, as well as in safety and orientation lighting such as exit signs and step markers.

2. Technical Parameters: In-Depth Objective Interpretation

The following sections provide a detailed analysis of the device's key technical parameters, derived from the absolute maximum ratings and typical operating conditions.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. They are not intended for normal operation.

• DC Forward Current (Torch Mode): 350 mA. This is the maximum continuous forward current the LED can handle.
• Peak Pulse Current: 1500 mA. This high current can only be applied under specific pulsed conditions (max 400 ms duration, 10% duty cycle), typical for camera flash operations.
• ESD Resistance (HBM): 8 kV. The device offers high electrostatic discharge protection according to the JEDEC JS-001-2017 (formerly JEDEC 3b) standard, which is critical for assembly and handling reliability.
• Junction Temperature (Tj): 150 °C. The maximum allowable temperature at the semiconductor junction.
• Operating & Storage Temperature: -40 °C to +85 °C (operating), -40 °C to +100 °C (storage).
• Thermal Resistance (Rth): 3.4 °C/W. This parameter indicates how effectively heat is transferred from the junction to the surroundings. A lower value signifies better thermal performance.
• Power Dissipation (Pulse Mode): 6.42 W. The maximum power the device can dissipate under pulsed conditions.
• Viewing Angle (2θ1/2): 120 degrees ± 5°. This defines the angular span where the luminous intensity is at least half of the peak intensity, resulting in a wide, Lambertian-like emission pattern.

Critical Notes: The device is not designed for reverse bias operation. Continuous operation at maximum ratings is prohibited as it will lead to degradation and potential failure. All reliability specifications are validated under controlled thermal management on a 1.0 cm² Metal Core Printed Circuit Board (MCPCB).

2.2 Electro-Optical Characteristics (Ts=25°C)

These parameters are measured under typical test conditions (50ms pulse, solder pad at 25°C) and represent the expected performance.

• Luminous Flux (Iv): 260 lm (Min), 300 lm (Typ) at IF=1000mA.
• Forward Voltage (VF): 2.85V (Min), 3.90V (Max) at IF=1000mA. The typical value falls within this range.
• Correlated Color Temperature (CCT): 5500K to 6500K, placing it in the \"cool white\" or \"daylight white\" color temperature range.

3. Binning System Explanation

To ensure consistency in mass production, LEDs are sorted into bins based on key performance parameters. This allows designers to select components that meet specific application requirements for brightness, voltage drop, and color.

3.1 Forward Voltage Binning

LEDs are categorized into three voltage bins at IF=1000mA:
- Bin 2832: VF = 2.85V to 3.25V.
- Bin 3235: VF = 3.25V to 3.55V.
- Bin 3539: VF = 3.55V to 3.90V.
This binning helps in designing stable driver circuits by accounting for the forward voltage variation.

3.2 Luminous Flux Binning

LEDs are sorted by their light output at IF=1000mA:
- Bin J7: Iv = 260 lm to 300 lm.
- Bin J8: Iv = 300 lm to 330 lm.
- Bin J9: Iv = 330 lm to 360 lm.
This ensures predictable brightness levels in the final application.

3.3 Chromaticity (Color) Binning

The white light chromaticity is defined by the CIE 1931 (x, y) color coordinates. The primary bin for this device is 5565, which targets a CCT range from 5500K to 6500K. The specific reference point for this bin is at coordinates (0.3166, 0.3003), with a defined quadrilateral tolerance box on the CIE chart. The measurement allowance for color coordinates is ±0.01.

4. Performance Curve Analysis

Graphical data provides insight into the device's behavior under varying operating conditions.

4.1 Relative Spectral Distribution

The spectral power distribution curve shows the intensity of light emitted at each wavelength. For a white LED based on a blue InGaN chip with a phosphor coating, the spectrum typically features a dominant blue peak from the chip and a broader yellow/red emission band from the phosphor. The combined output produces white light. The peak wavelength (λp) and the full spectral shape influence the Color Rendering Index (CRI) and the perceived color quality.

4.2 Typical Radiation Pattern

The polar radiation pattern illustrates the spatial distribution of light intensity. The provided curve indicates a near-Lambertian pattern, where intensity is approximately proportional to the cosine of the viewing angle. This results in a wide, uniform illumination suitable for general lighting and flash applications. The X and Y axis patterns are shown to be similar, indicating symmetrical emission.

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

This curve demonstrates the exponential relationship typical of a diode. The forward voltage increases with current but not linearly. Understanding this curve is essential for thermal management and driver design, as the power dissipated (Vf * If) generates heat.

4.4 Relative Luminous Flux vs. Forward Current

This graph shows how light output scales with drive current. Initially, the flux increases nearly linearly with current. However, at higher currents, efficiency droop occurs due to increased junction temperature and other semiconductor physics effects, causing the relative increase in flux to diminish. Operating beyond the recommended current reduces efficacy and accelerates aging.

4.5 CCT vs. Forward Current

This curve reveals how the correlated color temperature shifts with drive current. Typically, for phosphor-converted white LEDs, CCT may increase (light becomes cooler/bluer) at very high currents due to differential efficiency changes between the blue pump LED and the phosphor. The graph shows the CCT remaining relatively stable across the operational current range, which is desirable for consistent color performance.

5. Mechanical and Package Information

The physical dimensions and construction of the LED package are critical for PCB layout, thermal management, and optical design.

5.1 Package Dimension Drawing

The datasheet includes a detailed dimensioned drawing of the SMD (Surface-Mount Device) package. Key dimensions include the overall length, width, and height, as well as the pad (terminal) size and spacing. Tolerances are typically ±0.1mm unless otherwise specified. This drawing is essential for creating the PCB footprint (land pattern) in CAD software.

5.2 Polarity Identification

The package features a polarity marker. Correct orientation during assembly is mandatory to prevent reverse bias, which is not supported and can damage the device. The polarity is also indicated on the carrier tape for automated pick-and-place machines.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Parameters

The device can withstand a peak soldering temperature of 260°C, which is compatible with standard lead-free reflow profiles (e.g., IPC/JEDEC J-STD-020). The maximum allowable number of reflow cycles is 3. It is crucial to follow the recommended temperature profile (ramp-up, soak, reflow peak, and cooling rates) to prevent thermal shock and ensure reliable solder joints without damaging the LED component.

6.2 Moisture Sensitivity Level (MSL)

The component is rated MSL Level 1. This is the highest level of moisture resistance, meaning the device has an unlimited floor life at conditions ≤ 30°C / 85% Relative Humidity and does not require baking before use if stored within these conditions. This simplifies inventory management compared to higher MSL levels.

6.3 Storage Conditions

The recommended storage temperature range is -40°C to +100°C. Components should be kept in their original moisture-barrier bags with desiccant until ready for use to maintain the MSL 1 rating.

7. Packaging and Ordering Information

7.1 Packaging Specifications

The LEDs are supplied on embossed carrier tapes wound onto reels, which is the standard for automated SMD assembly. The datasheet provides dimensions for both the carrier tape (pocket pitch, width, etc.) and the reel (diameter, hub size). A standard reel contains 2000 pieces. The tape indicates the polarity and feed direction for the placement machine.

7.2 Product Labeling

The reel and packaging are labeled with key information for traceability and correct usage:
- P/N: The manufacturer's part number (e.g., ELCH08-NF5565J7J9283910-FDH).
- LOT NO: Manufacturing lot number for quality control.
- QTY: Quantity of pieces in the package.
- CAT: Luminous Flux Bin code (e.g., J7).
- HUE: Color Bin code (e.g., 5565).
- REF: Forward Voltage Bin code (e.g., 2832, 3235, 3539).
- MSL-X: Moisture Sensitivity Level.

8. Application Recommendations

8.1 Design Considerations

Thermal Management: This is the single most critical factor for LED performance and lifetime. The low thermal resistance (3.4°C/W) is only effective with adequate heat sinking. Use a PCB with sufficient copper area or a dedicated Metal Core PCB (MCPCB) to conduct heat away from the solder pads. The maximum substrate temperature is specified as 70°C at IF=1000mA.
Current Driving: Use a constant-current LED driver, not a constant-voltage source, to ensure stable light output and prevent thermal runaway. Respect the absolute maximum current ratings for both continuous (torch) and pulsed (flash) modes.
Optical Design: The wide 120-degree viewing angle is suitable for applications requiring broad coverage. For focused beams, secondary optics (lenses, reflectors) will be necessary. The Lambertian emission pattern simplifies optical modeling.

8.2 ESD Precautions

Although the device has high ESD protection (8kV HBM), standard ESD control practices should still be followed during handling and assembly (use of grounded workstations, wrist straps, etc.) to prevent cumulative damage or latent defects.

9. Technical Comparison and Differentiation

While a direct side-by-side comparison with other specific models is not provided in the datasheet, the key differentiating features of this LED can be inferred:
- High Luminous Efficacy: 87 lm/W at 1A is a competitive efficiency for a high-power SMD LED in its class, leading to lower energy consumption and reduced thermal load for a given light output.
- High-Current Pulse Capability: The 1500mA peak pulse rating for flash applications is a significant feature, enabling very bright, short-duration bursts of light suitable for camera flashes.
- Robust ESD Rating: 8kV HBM offers superior handling robustness compared to many LEDs with lower or unspecified ESD ratings.
- Comprehensive Binning: Three-parameter binning (flux, voltage, color) allows for tighter system performance control, which is advantageous for applications demanding color and brightness consistency.

10. Frequently Asked Questions (Based on Technical Parameters)

Q1: Can I drive this LED with a 3.3V power supply?
A: Not directly. The forward voltage (Vf) ranges from 2.85V to 3.90V at 1A. A 3.3V source might barely turn on a low-Vf unit but cannot provide proper current regulation. A constant-current driver circuit is required.

Q2: What is the difference between \"Torch Mode\" (350mA) and the test condition (1000mA)?
A: \"Torch Mode\" refers to the maximum continuous DC current (350mA). The 1000mA specification is for pulsed operation (e.g., 50ms pulses), typically used for performance benchmarking and flash applications. Continuous operation at 1000mA would exceed the maximum ratings and cause failure.

Q3: How do I interpret the luminous flux bin J7, J8, J9?
A: These are brightness bins. If your design requires a minimum of 300 lumens, you must select bins J8 or J9. Using bin J7 could result in units below your required brightness. Specify the required bin when ordering.

Q4: Is a heat sink necessary?
A: Absolutely. The power dissipation at 1A pulse can be up to nearly 4W (3.9V * 1A). Without proper heat sinking, the junction temperature will quickly exceed its limit, leading to rapid lumen depreciation, color shift, and catastrophic failure.

11. Practical Use Case Example

Scenario: Designing a Mobile Phone Camera Flash
1. Driver Selection: Choose a compact, high-efficiency switched-mode constant current driver IC capable of delivering a 1500mA pulse with tight control over pulse width (e.g., ~400ms) and duty cycle (<10%).
2. PCB Layout: Place the LED on a dedicated thermal pad connected to large copper pours or an internal ground plane. Use multiple vias under the pad to conduct heat to other layers. Keep the driver IC close to minimize trace inductance.
3. Optical Integration: A simple plastic lens or light guide will be placed over the LED to diffuse the light and eliminate hotspots, ensuring even illumination for the camera scene. The wide viewing angle of the LED helps in this diffusion.
4. Component Selection: For consistent flash color and brightness across millions of phones, specify tight bins: e.g., Color Bin 5565, Flux Bin J8 or J9, and a specific Voltage Bin to simplify driver design.

12. Operating Principle Introduction

This is a phosphor-converted white LED. The core is a semiconductor chip made of Indium Gallium Nitride (InGaN), which emits blue light when a forward voltage is applied and electrons recombine with holes across the chip's bandgap. This blue light is partially absorbed by a layer of cerium-doped yttrium aluminum garnet (YAG:Ce) phosphor coating the chip. The phosphor down-converts some of the blue photons to longer wavelengths in the yellow spectrum. The mixture of the remaining blue light and the converted yellow light is perceived by the human eye as white light. The ratio of blue to yellow emission determines the Correlated Color Temperature (CCT).

13. Technology Trends

The development of white LEDs follows several key trajectories:
- Increased Efficiency (lm/W): Ongoing improvements in internal quantum efficiency of the blue chip, light extraction from the package, and phosphor conversion efficiency drive efficacy higher, reducing energy consumption.
- Improved Color Quality: Moving beyond simple blue+YAG systems to multi-phosphor or violet-pump systems to achieve higher Color Rendering Index (CRI) and more consistent color across angles (Angular Color Uniformity).
- Higher Power Density & Miniaturization: As seen in this device, the trend is to pack more lumens into smaller packages, demanding ever-better thermal management solutions like advanced substrates and package materials.
- Enhanced Reliability: Improvements in materials (phosphors, encapsulants) and packaging techniques continue to extend operational lifetime and lumen maintenance (L70, L90 ratings).
- Smart and Integrated Solutions: The market is seeing growth in LEDs with integrated drivers, sensors, or communication capabilities (Li-Fi), though this datasheet describes a discrete, traditional component.