2820 SMD LED Datasheet - 2.8x2.0mm - Amber Color - 3.25V Typ - 0.975W - English Technical Document

1. Product Overview

The 2820-PA3001M-AM series is a high-performance, surface-mount device (SMD) LED designed for demanding applications, most notably in the automotive lighting sector. This LED utilizes phosphor conversion technology to produce a distinct amber color output. Its core advantages include a compact 2820 package footprint, robust construction suitable for automotive environments, and compliance with stringent industry standards such as AEC-Q102, RoHS, REACH, and halogen-free requirements. The primary target market is automotive exterior and interior lighting, where reliability, color consistency, and performance under varying thermal conditions are critical.

2. Technical Parameter Deep-Dive

2.1 Photometric and Electrical Characteristics

The LED's key performance is defined under a standard test current of 300 mA. At this drive current, the typical luminous flux is 75 lumens (lm), with a minimum of 60 lm and a maximum of 90 lm. The dominant wavelength is defined by its chromaticity coordinates, with a typical CIE-x of 0.575 and CIE-y of 0.418, placing it firmly in the amber region of the color spectrum. The forward voltage (Vf) typically measures 3.25 volts, with a range from 2.75V to 3.75V at 300 mA. This parameter is crucial for driver design and thermal management calculations. The device offers a wide 120-degree viewing angle, ensuring good spatial light distribution.

2.2 Absolute Maximum Ratings and Thermal Properties

To ensure long-term reliability, the device must not be operated beyond its Absolute Maximum Ratings. The maximum continuous forward current is 350 mA, with a surge current capability of 750 mA for pulses ≤10 μs. The maximum power dissipation is 1225 mW. The junction temperature (Tj) must not exceed 150°C, with an operating temperature range of -40°C to +125°C. Thermal management is a key design consideration; the thermal resistance from the junction to the solder point is specified with two values: an electrical measurement (Rth JS el) of 15 K/W and a real measurement (Rth JS real) of 22 K/W. The higher real value should be used for accurate thermal modeling in the application.

3. Binning System Explanation

The LEDs are sorted into bins to ensure consistency in key parameters, which is vital for applications requiring uniform appearance and performance.

3.1 Luminous Flux Binning

Luminous flux is categorized into bins F6, F7, and F8, representing minimum-to-maximum flux ranges of 60-70 lm, 70-80 lm, and 80-90 lm, respectively. This allows designers to select LEDs based on the required brightness level for their specific application.

3.2 Forward Voltage Binning

Forward voltage is binned to aid in circuit design and to group LEDs with similar electrical characteristics. Bins include 2730 (2.75V-3.00V), 3032 (3.00V-3.25V), 3235 (3.25V-3.50V), and 3537 (3.50V-3.75V). Matching Vf bins can help achieve more uniform current sharing in multi-LED arrays.

3.3 Color Binning

The amber color is tightly controlled within specific chromaticity regions on the CIE 1931 diagram. Two primary bins, YA and YB, are defined with precise coordinate boundaries. Bin YA covers a yellower amber, while bin YB covers a redder amber. The provided chart and coordinate tables allow designers to specify the exact color point required for their application, ensuring visual consistency across multiple units or products.

4. Performance Curve Analysis

4.1 IV Curve and Luminous Flux vs. Current

The Forward Current vs. Forward Voltage graph shows a characteristic exponential relationship. Understanding this curve is essential for designing the current-limiting circuitry. The Relative Luminous Flux vs. Forward Current graph demonstrates that light output increases with current but begins to show signs of saturation and reduced efficiency at higher currents, emphasizing the importance of operating within recommended conditions.

4.2 Temperature Dependence

The performance of an LED is significantly affected by temperature. The Relative Luminous Flux vs. Junction Temperature graph shows a clear decrease in light output as the junction temperature rises. For instance, at 125°C, the flux may be only 70-80% of its value at 25°C. The Forward Voltage vs. Junction Temperature graph shows a negative temperature coefficient, where Vf decreases linearly with increasing temperature. This property is sometimes used for temperature sensing. The Chromaticity Shift vs. Junction Temperature graphs indicate how the amber color point may shift slightly with temperature, which is a consideration for color-critical applications.

4.3 Spectral Distribution and Radiation Pattern

The Relative Spectral Distribution graph confirms the amber color, showing a broad peak in the yellow-orange region with minimal emission in the blue spectrum, as expected from a phosphor-converted LED. The Typical Diagram of Radiation Characteristics illustrates the spatial intensity distribution, confirming the 120° viewing angle where intensity falls to half of its peak value at ±60° from the centerline.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED is housed in a 2820 package, which measures 2.8mm in length and 2.0mm in width. The detailed mechanical drawing provides all critical dimensions, including lens height, pad sizes, and tolerances (typically ±0.1mm). This information is necessary for PCB footprint design and ensuring proper clearance in the final assembly.

5.2 Recommended Soldering Pad Layout

A dedicated drawing shows the optimal PCB land pattern (solder pad) design. Following this recommendation is crucial for achieving reliable solder joints, proper thermal transfer from the LED's thermal pad to the PCB, and preventing tombstoning or misalignment during reflow soldering. The design typically includes a central thermal pad for heat dissipation and two smaller anode/cathode pads.

5.3 Polarity Identification

The datasheet indicates polarity markings on the device itself. Correct orientation during placement is essential for the LED to function. The cathode is typically marked, often with a notch, a green marking, or a different pad size/shape.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

The device is rated for reflow soldering with a peak temperature of 260°C for a maximum of 30 seconds. A detailed reflow profile graph is typically provided, showing the recommended preheat, soak, reflow, and cooling stages. Adhering to this profile prevents thermal damage to the LED package, solder joints, and internal die.

6.2 Precautions for Use

General handling precautions include avoiding mechanical stress on the lens, protecting the device from electrostatic discharge (ESD rated at 8kV HBM), and storing in a dry environment (MSL 2). The device is not designed for reverse voltage operation. The forward current derating curve is critical: as the solder pad temperature increases, the maximum permissible continuous current must be reduced. For example, at a pad temperature of 125°C, the maximum current is 350 mA.

7. Packaging and Ordering Information

7.1 Packaging Specifications

The LEDs are supplied on tape and reel for automated assembly. The packaging information details the reel dimensions, tape width, pocket spacing, and orientation of components on the tape. This data is necessary for programming pick-and-place machines.

7.2 Part Number and Ordering Code

The part number 2820-PA3001M-AM follows a specific structure that encodes key attributes like package size (2820), color (PA for Phosphor Amber), nominal current (300mA), and other internal codes. The ordering information clarifies how to specify the desired bins for luminous flux (F-code), forward voltage (V-code), and color (C-code) to get the exact performance required.

8. Application Suggestions

8.1 Typical Application Scenarios

The primary application is automotive lighting. This includes daytime running lights (DRLs), turn signals, side marker lights, interior ambient lighting, and center high-mount stop lights (CHMSL). Its amber color and high reliability make it ideal for safety-critical signaling functions.

8.2 Design Considerations

Key design factors include:

• Thermal Management: Use a PCB with adequate thermal vias under the thermal pad, possibly connected to a copper pour or heatsink, to keep the junction temperature low and maintain light output and longevity.
• Drive Circuitry: Implement a constant-current driver suitable for the LED's Vf range and capable of providing up to 350 mA. Consider inrush current protection.
• Optical Design: The 120° viewing angle may require secondary optics (lenses, reflectors) to shape the beam for specific applications like turn signals.
• Environmental Protection: For exterior applications, ensure the LED is adequately protected from moisture and contaminants, often via a conformal coating or encapsulation within a sealed lamp assembly.

9. Technical Comparison and Differentiation

Compared to standard non-automotive grade amber LEDs, the 2820-PA3001M-AM series offers distinct advantages:

• Automotive Qualification (AEC-Q102): It undergoes rigorous testing for temperature cycling, humidity, high-temperature operation life (HTOL), and other stresses, ensuring reliability in the harsh automotive environment.
• Sulfur Resistance (Class A1): Tested and certified to withstand sulfur-containing atmospheres, which is a common failure mode in certain geographic regions or industrial environments.
• Halogen-Free: Compliant with environmental regulations restricting bromine and chlorine content.
• Consistent Binning: Tight binning on flux, voltage, and color ensures predictable performance and uniform appearance in multi-LED applications, which is less guaranteed with commercial-grade parts.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the actual power consumption of this LED?
A: At the typical operating point of 300 mA and 3.25V, the electrical power is 0.975 Watts. However, the maximum power dissipation rating of 1.225W considers the total energy, including the non-radiative (heat) portion.

Q: How do I interpret the two different thermal resistance values (15 K/W and 22 K/W)?
A: Use the higher value (22 K/W, Rth JS real) for thermal design. The lower value (15 K/W) is derived from an electrical measurement method and may not fully represent the thermal path in a real soldered application.

Q: Can I drive this LED with a constant voltage source?
A: It is strongly discouraged. LEDs are current-driven devices. A small change in forward voltage (due to temperature or bin variation) can cause a large change in current with a constant voltage source, potentially leading to thermal runaway and device failure. Always use a constant-current driver.

Q: The datasheet shows a surge current rating. Can I use this for pulsed operation?
A: Yes, for short pulses. The Permissible Pulse Handling Capability graph shows the permissible peak current (IFP) for various pulse widths (tp) and duty cycles (D). For example, at a 1% duty cycle, much higher peak currents than 350 mA are allowed for very short pulses.

11. Practical Design Case Study

Scenario: Designing an automotive rear turn signal cluster using 6 LEDs.
1. Target Specification: Meet regulatory photometric requirements (intensity, color).
2. LED Selection: Choose bin F7 for flux (70-80 lm) and bin YB for a specific amber hue. Select Vf bin 3032 for predictable driver design.
3. Thermal Design: Design a PCB with a 2-oz copper layer and an array of thermal vias directly under each LED's thermal pad, connected to a large rear copper plane acting as a heatsink. Use the derating curve to ensure pad temperature stays below 100°C at ambient 85°C to allow full 300mA drive.
4. Electrical Design: Use a single constant-current driver capable of 1.8A (6 * 300mA). Connect the 6 LEDs in series to ensure identical current through each, requiring a driver output voltage > 6 * 3.75V (max Vf) = 22.5V.
5. Optical/Mechanical: Design a housing with a diffuser lens to blend the light from the 6 discrete sources into a uniform illuminated area, complying with the required viewing angles for turn signals.

12. Technology Principle Introduction

This LED is a phosphor-converted amber (PCA) device. It likely uses a blue or near-UV semiconductor die (chip). This primary light from the die is not emitted directly. Instead, it excites a layer of phosphor material deposited on or around the die. This phosphor absorbs the higher-energy blue/UV photons and re-emits lower-energy photons across a broader spectrum, predominantly in the yellow, orange, and red regions. The combination of the remaining unconverted blue light and the phosphor's yellow-red emission results in the perceived amber color. This method allows for precise tuning of the color coordinates by adjusting the phosphor composition and thickness, offering advantages in color consistency and stability compared to direct amber semiconductor LEDs.

13. Industry Trends and Developments

The automotive LED lighting market continues to evolve with several clear trends influencing devices like the 2820 series:

• Increased Efficiency (lm/W): Ongoing improvements in semiconductor epitaxy, phosphor efficiency, and package design drive higher luminous efficacy, allowing for brighter lights or lower power consumption.
• Miniaturization: While the 2820 is a standard package, there is a push for smaller, high-power density packages (e.g., 2016, 1515) to enable sleeker, more compact lamp designs.
• Enhanced Reliability and Robustness: Standards like AEC-Q102 are becoming the baseline. Further development focuses on improved resistance to specific stressors like electrostatic discharge (ESD), reverse bias, and harsh chemical environments.
• Smart and Adaptive Lighting: LEDs are becoming integral to advanced systems like adaptive driving beams (ADB) and pixelated headlights. This drives demand for LEDs with faster switching capabilities and tighter optical control, though the 2820 is more suited for conventional signaling functions.
• Color Tuning and Expanded Gamut: For interior ambient lighting, there is growing interest in multi-color or tunable-white LEDs, moving beyond fixed-color LEDs like this amber device.