LED Datasheet 2820 Red SMD - Package 2.8x2.0mm - Voltage 2.3V - Power 0.46W - Automotive Grade

1. Product Overview

The 2820-UR2001M-AM series represents a high-reliability, surface-mount LED component engineered for demanding automotive lighting applications. This device is characterized by its compact 2820 package footprint, delivering a typical luminous flux of 40 lumens at a drive current of 200mA. The primary emitted color is red, with a dominant wavelength typically at 618nm. A key differentiator of this series is its compliance with the AEC-Q102 Rev A standard, which is the automotive industry's benchmark for discrete optoelectronic semiconductor devices, ensuring performance and longevity under harsh environmental conditions. The LED is also qualified for sulfur resistance (Class A1), making it suitable for environments with high atmospheric contamination.

1.1 Core Advantages

The series offers several distinct advantages for design engineers. Its SMD (Surface Mount Device) package facilitates automated assembly processes, improving manufacturing efficiency and consistency. The wide 120-degree viewing angle provides uniform illumination, which is critical for automotive signal functions like tail lights. The component's construction meets stringent environmental standards, being fully compliant with RoHS (Restriction of Hazardous Substances), REACH regulations, and is Halogen-Free, aligning with global environmental and safety directives. The integrated design ensures robust ESD (Electrostatic Discharge) protection rated at 2KV (HBM), enhancing handling and assembly reliability.

1.2 Target Market and Applications

The primary target market is the automotive electronics sector. Specific applications include, but are not limited to, exterior lighting modules such as rear combination lamps (tail lights, stop lights), center high-mount stop lights (CHMSL), and interior ambient lighting. Its reliability specifications make it a candidate for any application requiring consistent performance across a wide temperature range (-40°C to +125°C).

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, explaining their significance for circuit design and system integration.

2.1 Photometric and Optical Characteristics

The central photometric parameter is the Luminous Flux (Iv), specified as 33 Min, 40 Typ, 52 Max lumens at a forward current (IF) of 200mA and a thermal pad temperature of 25°C. The ±8% measurement tolerance indicates the expected variation in light output between individual units under identical test conditions. The Dominant Wavelength (λd) defines the perceived color of the LED, specified between 612nm and 624nm, with a typical value of 618nm (deep red). The Viewing Angle of 120° (with a ±5° tolerance) is defined as the full angle where the luminous intensity is half of its peak value. This wide beam pattern is ideal for applications requiring broad-area illumination rather than a focused spot.

2.2 Electrical Characteristics

The Forward Voltage (VF) is a critical parameter for driver design. At 200mA, VF ranges from 2.00V to 2.75V, with a typical value of 2.3V. This variance necessitates a current-regulated, not voltage-regulated, power supply to ensure consistent light output and prevent thermal runaway. The Absolute Maximum Ratings define the operational limits: a continuous forward current (IF) of 250mA, a surge current (IFM) of 1000mA for pulses ≤10μs, and a maximum power dissipation (Pd) of 687.5mW. Exceeding these ratings may cause permanent damage.

2.3 Thermal Characteristics

Thermal management is paramount for LED performance and lifetime. The Thermal Resistance from the junction to the solder point is specified in two ways: a 'Real' value (Rth JS real) of 18 Typ / 24 Max K/W, and an 'Electrical' value (Rth JS el) of 12 Typ / 16 Max K/W. The electrical method is derived from the temperature coefficient of VF and is typically lower. Designers should use the higher 'Real' value for conservative thermal design. The maximum permissible Junction Temperature (TJ) is 150°C. The Forward Current Derating Curve graphically shows how the maximum allowable continuous current must be reduced as the solder pad temperature (Ts) increases above 25°C to keep the junction temperature within safe limits.

3. Binning System Explanation

To manage manufacturing variances, LEDs are sorted into performance bins. This allows designers to select parts that meet specific system requirements.

3.1 Luminous Flux Binning

Units are categorized into three flux bins: F2 (33-39 lm), F3 (39-45 lm), and F4 (45-52 lm). This enables selection based on required brightness levels, potentially optimizing cost versus performance.

3.2 Forward Voltage Binning

Voltage bins are: 2022 (2.00-2.25V), 2225 (2.25-2.50V), and 2527 (2.50-2.75V). Matching LEDs from the same voltage bin can help achieve more uniform current sharing in parallel configurations.

3.3 Dominant Wavelength Binning

The color is binned into four groups: 1215 (612-615nm), 1518 (615-618nm), 1821 (618-621nm), and 2124 (621-624nm). This ensures color consistency within a lighting assembly, which is critical for aesthetic and regulatory reasons in automotive applications.

4. Performance Curve Analysis

The provided graphs offer crucial insights into the LED's behavior under different operating conditions.

4.1 IV Curve and Relative Luminous Flux

The Forward Current vs. Forward Voltage graph shows the exponential relationship typical of a diode. The Relative Luminous Flux vs. Forward Current graph demonstrates that light output increases sub-linearly with current, emphasizing the importance of thermal management at higher drive levels.

4.2 Temperature Dependence

The Relative Forward Voltage vs. Junction Temperature graph shows VF decreases linearly with increasing temperature (negative temperature coefficient), which can be used for junction temperature estimation. The Relative Luminous Flux vs. Junction Temperature graph indicates light output decreases as temperature rises, a key consideration for maintaining brightness in hot environments. The Relative Wavelength vs. Junction Temperature graph shows the dominant wavelength increases (shifts towards longer wavelengths) with temperature.

4.3 Spectral Distribution and Pulse Handling

The Relative Spectral Distribution curve confirms the monochromatic red output, peaking around the dominant wavelength. The Permissible Pulse Handling Capability graph defines the maximum allowable non-repetitive or pulsed current for various pulse widths (tp) and duty cycles (D), which is vital for designs using PWM (Pulse Width Modulation) dimming or short-duration high-current pulses.

5. Mechanical and Package Information

5.1 Physical Dimensions

The LED is housed in a 2820 package, which denotes nominal dimensions of 2.8mm in length and 2.0mm in width. The detailed mechanical drawing specifies all critical dimensions, including overall height, lead spacing, and the size/location of the thermal pad. Tolerances are typically ±0.1mm unless otherwise noted.

5.2 Recommended Solder Pad Design

A land pattern (footprint) is provided for PCB (Printed Circuit Board) design. This includes the dimensions for the anode/cathode solder pads and the central thermal pad. Adhering to this recommendation is essential for achieving reliable solder joints, effective heat transfer from the thermal pad to the PCB, and preventing tombstoning during reflow.

5.3 Polarity Identification

The datasheet diagram indicates polarity markings on the device. Correct orientation is crucial for circuit operation. Typically, the cathode is marked, often with a notch, a dot, or a green marking on the package.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

The component is rated for a maximum soldering temperature of 260°C for 30 seconds. A detailed reflow profile graph is typically provided, specifying the preheat, soak, reflow (peak temperature and time above liquidus), and cooling ramp rates. Following this profile prevents thermal shock and ensures solder joint integrity.

6.2 Precautions for Use

General handling precautions include avoiding mechanical stress on the LED lens, preventing contamination of the optical surface, and observing standard ESD (Electrostatic Discharge) precautions during handling and assembly. The device is not designed for reverse voltage operation.

6.3 Storage Conditions

The specified storage temperature range is from -40°C to +125°C. For long-term storage, it is recommended to keep components in their original moisture-barrier bags (MSL 2 rating indicates a floor life of 1 year after the bag is opened, provided the environment is ≤30°C/60% RH).

7. Packaging and Ordering Information

7.1 Packaging Specifications

The LEDs are supplied on tape and reel for compatibility with automated pick-and-place assembly equipment. The packaging information details the reel dimensions, tape width, pocket spacing, and component orientation on the tape.

7.2 Part Numbering System

The part number 2820-UR2001M-AM is decoded as follows: 2820 = Package family; UR = Color (Red); 200 = Test Current (200mA); 1 = Lead Frame Type (1=Gold); M = Brightness Level (Medium); AM = Automotive application. This structured naming allows precise identification of the component's key attributes.

8. Application Recommendations

8.1 Typical Application Circuits

For constant brightness, a series resistor with a constant voltage supply is the simplest drive method, though inefficient. For automotive applications, a dedicated LED driver IC is recommended. This driver should provide a constant current output, offer PWM dimming capability, and include protection features like over-voltage, over-current, and thermal shutdown. The LED should be driven at or below the recommended 200mA for optimal lifetime, using the derating curve for elevated ambient temperatures.

8.2 Thermal Design Considerations

Effective heat sinking is critical. The PCB should use a sufficient copper area (connected to the thermal pad via multiple vias) to act as a heat spreader. The thermal resistance of the system (junction-to-ambient, Rth JA) must be low enough to keep the junction temperature well below 150°C at the intended operating current and ambient temperature. Calculations should use the maximum thermal resistance (Rth JS real) and consider the worst-case ambient conditions.

8.3 Optical Design Considerations

The wide 120° viewing angle may require secondary optics (lenses, light guides, or reflectors) to shape the beam for specific applications like signal lights. The material of these optics must be compatible with the LED's wavelength and capable of withstanding the operating temperature and UV exposure if used outdoors.

9. Technical Comparison and Differentiation

Compared to standard commercial-grade LEDs, the 2820-UR2001M-AM series is distinguished by its AEC-Q102 qualification, which involves rigorous testing for temperature cycling, humidity resistance, high-temperature operating life, and other stressors. Its Sulfur Resistance (Class A1) is another key differentiator, protecting the silver-plated components from corrosion in polluted atmospheres—a common issue in automotive and industrial settings. The combination of a compact SMD package with this level of robustness is a significant advantage for space-constrained, high-reliability applications.

10. Frequently Asked Questions (FAQ)

10.1 What is the difference between the 'Typ.' and 'Max.' forward voltage?

The 'Typ.' (Typical) value of 2.3V represents the average or most common value from production. The 'Max.' value of 2.75V is the upper limit guaranteed by the specification. Your driver circuit must be designed to handle the maximum VF to ensure it can provide the required current to all units, including those at the high end of the voltage distribution.

10.2 Can I drive this LED with a 3.3V supply and a resistor?

Yes, but careful calculation is needed. Assuming a typical VF of 2.3V at 200mA, the resistor would need to drop 1.0V (3.3V - 2.3V). Using Ohm's Law (R = V/I), R = 1.0V / 0.2A = 5 Ohms. The resistor power rating would be P = I²R = (0.2)² * 5 = 0.2W, so a 0.25W or 0.5W resistor is recommended. However, this method is inefficient (wastes power in the resistor) and brightness will vary with changes in VF. A constant current driver is superior for performance and efficiency.

10.3 Why is the luminous flux measured at a thermal pad temperature of 25°C?

The light output of an LED is highly dependent on the temperature of the semiconductor junction. Measuring at a controlled thermal pad temperature (a proxy for junction temperature) provides a consistent and repeatable baseline for comparing performance. In real applications, the junction will be hotter, and the actual light output will be lower, as shown in the Relative Luminous Flux vs. Junction Temperature graph.

11. Design and Usage Case Study

Scenario: Designing a rear tail light for a passenger vehicle. The design requires uniform red illumination across a defined area. The 2820 LED is selected for its automotive-grade reliability, compact size, and wide viewing angle. A cluster of 8 LEDs is arranged in a line. They are driven by a single automotive-qualified buck-mode constant current LED driver IC, set to deliver 200mA. The driver includes PWM dimming input, allowing the same LEDs to function as both tail lights (dimmed) and brake lights (full brightness). The PCB is a 2-ounce copper board with large thermal pads connected to an internal ground plane via thermal vias to dissipate heat. The LEDs are chosen from the same luminous flux (F3) and dominant wavelength (1821) bins to ensure consistent brightness and color across the assembly. The final design is validated through temperature cycling, humidity, and vibration tests per automotive standards.

12. Operating Principle

An LED (Light Emitting Diode) is a semiconductor p-n junction device. When a forward voltage exceeding the junction's built-in potential is applied, electrons from the n-type region recombine with holes from the p-type region within the active layer. This recombination process releases energy in the form of photons (light). The specific wavelength (color) of the emitted light is determined by the energy bandgap of the semiconductor materials used in the active region. In this device, the materials are engineered to produce photons in the red portion of the visible spectrum (approximately 618nm). The epoxy lens encapsulates the semiconductor die, provides mechanical protection, and shapes the emitted light pattern.

13. Technology Trends

The general trend in automotive LED technology is towards higher efficiency (more lumens per watt), increased power density (more light from smaller packages), and enhanced reliability under even more extreme conditions. There is a growing integration of smart features, such as embedded sensors or driver electronics within the LED package. Furthermore, the push for standardized communication protocols (like LIN or CAN bus) for lighting control is increasing. The focus on sustainability continues to drive the elimination of hazardous substances and improvements in manufacturing processes to reduce environmental impact.