2820-SR2001M-AM LED Datasheet - SMD Package 2.8x2.0mm - Super Red 632nm - 27lm @ 200mA - Automotive Grade

1. Product Overview

The 2820-SR2001M-AM series represents a high-performance, surface-mount LED component engineered specifically for demanding automotive lighting environments. This device is part of a product family characterized by its compact 2820 footprint (2.8mm x 2.0mm), offering a compelling balance of luminous output, reliability, and form factor. The core application is automotive lighting, where consistent performance under harsh conditions is paramount. Its key advantages include compliance with stringent automotive qualification standards like AEC-Q102, robust construction for high-reliability soldering processes, and a design optimized for thermal management, ensuring stable light output over the operational temperature range.

1.1 Core Features and Compliance

The LED is packaged in a standard SMD (Surface Mount Device) format, facilitating automated assembly processes. It emits in the Super Red spectrum with a typical dominant wavelength of 632 nanometers. A primary performance metric is its typical luminous flux of 27 lumens when driven at a forward current of 200 milliamperes. The device offers a wide 120-degree viewing angle, providing broad illumination. It is designed with a degree of robustness against electrostatic discharge, rated for 2kV (Human Body Model). The component is rated MSL 2 (Moisture Sensitivity Level 2), indicating its shelf life and handling requirements before reflow soldering. Crucially, it is qualified according to the AEC-Q102 Rev A standard, which is the stress test qualification for discrete optoelectronic semiconductors in automotive applications. It also meets Sulfur Test Criteria Class A1, offering resistance to corrosive sulfur-containing atmospheres. The product is compliant with RoHS (Restriction of Hazardous Substances) and REACH regulations, and is manufactured to be Halogen Free, with bromine and chlorine content below specified limits (Br <900 ppm, Cl <900 ppm, Br+Cl < 1500 ppm).

2. Technical Parameter Analysis

This section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters defined in the datasheet, explaining their significance for design engineers.

2.1 Photometric and Optical Characteristics

The primary optical characteristic is the Luminous Flux (Iv), with a typical value of 27 lumens at a forward current (IF) of 200mA. The minimum and maximum values are specified as 20 lm and 33 lm, respectively, under the same condition. This range is directly linked to the binning structure discussed later. The Dominant Wavelength (λd) is typically 632 nm, defining the perceived color of the Super Red light, with a range from 627 nm to 639 nm. The Viewing Angle (φ) is specified as 120 degrees, which is the full angle at which the luminous intensity is half of the peak intensity. This wide angle is beneficial for applications requiring diffuse or area lighting rather than a focused beam.

2.2 Electrical Characteristics

The Forward Voltage (VF) is a critical parameter for driver design. At 200mA, the typical VF is 2.3 volts, with a range from 2.00V to 2.75V. This variance necessitates proper voltage binning for consistent system performance. The Forward Current (IF) has a recommended operating range of 25mA to 250mA, with 200mA being the test condition for most specifications. Exceeding the absolute maximum rating of 250mA can lead to permanent damage. The device is not designed for reverse operation, meaning applying a reverse voltage can cause immediate failure; therefore, circuit protection (like a series diode in parallel arrays) is essential if reverse bias is possible.

2.3 Thermal and Reliability Ratings

Thermal management is crucial for LED longevity and performance. The Thermal Resistance from the junction to the solder point is given by two values: a real thermal resistance (Rth JS real) of 18 K/W (typical) and an electrical method-derived value (Rth JS el) of 12 K/W (typical). Designers should use the real thermal resistance for more accurate junction temperature calculations. The Junction Temperature (TJ) must not exceed 150°C. The Operating Temperature (Topr) range is from -40°C to +125°C, suitable for automotive under-hood and exterior applications. The Power Dissipation (Pd) absolute maximum is 687.5 mW. The device can withstand a Surge Current (IFM) of 1000 mA for very short pulses (t <= 10 μs, duty cycle 0.005), which is relevant for inrush or transient conditions. The maximum Reflow Soldering Temperature is 260°C for 30 seconds, defining the peak temperature profile during assembly.

3. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins. The 2820-SR2001M-AM uses a three-dimensional binning system.

3.1 Luminous Flux Binning

Luminous flux is sorted into three bins: E8 (20-23 lm), E9 (23-27 lm), and F1 (27-33 lm). The \"M\" in the part number indicates a Medium brightness level, which typically corresponds to the central bin (E9). Designers must select the appropriate bin based on the required minimum light output for their application, considering the 8% measurement tolerance.

3.2 Forward Voltage Binning

Forward voltage is binned to aid in current matching, especially when LEDs are connected in parallel. The bins are: 2022 (2.00-2.25V), 2225 (2.25-2.50V), and 2527 (2.50-2.75V). Using LEDs from the same voltage bin in a parallel configuration helps ensure more uniform current distribution and brightness.

3.3 Dominant Wavelength Binning

Color consistency is managed through dominant wavelength bins, grouped in 3nm steps: 2730 (627-630 nm), 3033 (630-633 nm), 3336 (633-636 nm), and 3639 (636-639 nm). The typical 632 nm value falls within the 3033 or 3336 bins. For applications where precise color matching is critical, specifying a tight wavelength bin is necessary.

4. Performance Curve Analysis

The datasheet provides several graphs that illustrate the device's behavior under varying conditions, which are essential for robust system design.

4.1 Forward Current vs. Forward Voltage (IV Curve)

The graph shows the exponential relationship between forward current and forward voltage. At the typical operating point of 200mA, the voltage is approximately 2.3V. This curve is vital for designing the current-limiting circuitry, whether using a simple resistor or a constant-current driver. The slope indicates the dynamic resistance of the LED.

4.2 Relative Luminous Flux vs. Forward Current

This graph demonstrates that light output increases super-linearly with current up to a point. While driving at higher currents yields more light, it also generates more heat, which can reduce efficiency and lifespan. The 200mA test point is a good balance between output and reliability for this device.

4.3 Temperature Dependency Graphs

Three key graphs show performance variation with junction temperature: Relative Forward Voltage vs. Junction Temperature shows VF decreases linearly with increasing temperature (approximately -2 mV/°C), which can be used for crude temperature sensing. Relative Luminous Flux vs. Junction Temperature shows that light output decreases as temperature rises, a characteristic of all LEDs. Effective heat sinking is required to maintain stable brightness. Relative Wavelength Shift vs. Junction Temperature indicates the dominant wavelength shifts slightly with temperature (typically 0.1 nm/°C for red LEDs), which is usually negligible for most applications but may be relevant for color-critical uses.

4.4 Forward Current Derating Curve

This is one of the most critical graphs for reliability. It shows the maximum allowable forward current as a function of the solder pad temperature. As the pad temperature increases, the maximum permissible current decreases linearly. For example, at the maximum solder pad temperature of 125°C, the maximum allowed current is 250mA (the absolute max rating). To ensure long life, it is recommended to operate significantly below this derating line. The curve also specifies a minimum operating current of 25mA.

4.5 Permissible Pulse Handling Capability

This graph defines the maximum allowable non-repetitive or repetitive pulse current for a given pulse width (tp) and duty cycle (D). It allows designers to understand the LED's capability to handle short, high-current pulses, which is useful for PWM dimming or transient conditions. The curves show that for very short pulses (e.g., 10 μs), the current can significantly exceed the DC maximum rating.

4.6 Spectral Distribution and Radiation Pattern

The relative spectral distribution graph shows a narrow peak around 632 nm, characteristic of a high-efficiency red LED. The typical radiation pattern diagram (not fully detailed in the provided excerpt but referenced) would illustrate the spatial distribution of light, confirming the 120° viewing angle with a Lambertian or similar pattern.

5. Mechanical and Packaging Information

5.1 Mechanical Dimensions

The LED uses the standard 2820 package outline. The dimensions are provided in a detailed drawing (implied by section 3). Key features include the overall length and width (2.8mm x 2.0mm), the lens geometry, and the location of the cathode and anode terminals. The cathode is typically marked by a visual indicator such as a notch, cut corner, or dot on the package. Tolerances for non-critical dimensions are ±0.1mm.

5.2 Recommended Soldering Pad Layout

Section 4 provides a land pattern design for the PCB. Adhering to this recommended footprint is critical for reliable soldering, proper thermal transfer, and preventing tombstoning during reflow. The design includes pads for the two electrical terminals and a central thermal pad. The thermal pad is essential for conducting heat away from the LED junction to the PCB copper, which acts as a heat sink. The dimensions ensure correct solder fillet formation and component alignment.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

The device is compatible with standard infrared or convection reflow soldering processes. The specified maximum condition is a peak temperature of 260°C for 30 seconds. A typical lead-free profile should be used, with preheat, soak, reflow, and cooling stages carefully controlled to avoid thermal shock and ensure proper solder joint formation. The MSL 2 rating means the component must be baked if exposed to ambient air for longer than its specified floor life (typically 1 year when stored at <10% RH and <30°C) before being subjected to reflow.

6.2 Precautions for Use

General handling precautions apply: avoid mechanical stress on the lens, protect from electrostatic discharge using appropriate ESD controls (even with its 2kV rating), and store in dry, controlled conditions per the MSL rating. During soldering, ensure the thermal pad makes good contact with the PCB pad to maximize heat dissipation.

7. Packaging and Ordering Information

7.1 Part Number Decoding

The part number 2820-SR2001M-AM is structured as follows: 2820: Product family and package size (2.8mm x 2.0mm). SR: Color code for Super Red. 200: Test current in milliamperes (200mA). 1: Lead frame type (1 = Gold-plated). M: Brightness level (M = Medium, corresponding to a specific luminous flux bin). AM: Designates Automotive application and qualification.

7.2 Color Code Reference

The datasheet includes a comprehensive table mapping color symbols to descriptions (e.g., SR=Super Red, UR=Red, UG=Green, UB=Blue, C=Cool White, WW=Warm White, PA=Phosphor Converted Amber). This allows identification of other variants in the same 2820 package family.

7.3 Packaging Information

The LEDs are supplied on tape and reel for automated pick-and-place assembly. Standard reel quantities (e.g., 2000 or 4000 pieces per reel) and tape dimensions are provided to configure feeders on assembly machines correctly.

8. Application Suggestions and Design Considerations

8.1 Typical Application Scenarios

The primary application is automotive lighting. This includes: Exterior Signaling: Center High-Mount Stop Lights (CHMSL), rear combination lamps (stop/tail/turn), side marker lights. Interior Lighting: Dashboard backlighting, switch illumination, ambient lighting. Advanced Driver Assistance Systems (ADAS): Sensor illumination where specific wavelength is required. Its AEC-Q102 qualification, wide temperature range, and sulfur resistance make it suitable for these harsh environments.

8.2 Design Considerations

Thermal Management: The most critical aspect. Use the thermal resistance (Rth JS real = 18 K/W) to calculate the junction temperature rise above the PCB temperature. Ensure adequate copper area (thermal pad) on the PCB, possibly with thermal vias to inner layers or a backside plane, to keep the solder pad temperature low. Refer to the derating curve. Current Drive: Use a constant-current driver for stable light output, especially over temperature. If using a series resistor, account for the forward voltage bin spread and supply voltage tolerance. Optics: The 120° viewing angle may require secondary optics (lenses, light guides) to shape the beam for specific applications. ESD Protection: Implement standard ESD precautions during handling and assembly. In the circuit, consider transient voltage suppression if the LED is connected to long wires or noisy automotive buses.

9. Technical Comparison and Differentiation

While a direct competitor comparison is not in the datasheet, key differentiators of this series can be inferred: Automotive Qualification: AEC-Q102 compliance is a significant differentiator from commercial-grade LEDs, involving rigorous stress tests for temperature cycling, humidity, high-temperature operating life, etc. Sulfur Resistance: Class A1 sulfur test criteria is crucial for automotive and industrial applications where atmospheric sulfur can corrode silver-based components. Halogen-Free: Meets environmental and safety standards required by many OEMs. Thermal Performance: The specified thermal resistance values allow for more accurate thermal modeling compared to parts that only provide a maximum power rating.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the actual brightness I can expect?
A: The typical value is 27 lm at 200mA. However, you must design based on the minimum bin you are willing to accept (e.g., 20 lm for E8 bin) to guarantee system performance. Contact the supplier for specific bin availability.

Q: Can I drive this LED with PWM for dimming?
A: Yes, LEDs are ideal for PWM dimming. Ensure the peak current during the \"on\" pulse does not exceed the ratings from the \"Permissible Pulse Handling Capability\" graph for your chosen frequency and duty cycle. A frequency above 100Hz is recommended to avoid visible flicker.

Q: How do I calculate the required heatsink?
A: 1) Determine your operating current (e.g., 200mA) and corresponding VF (e.g., 2.3V). Power = 0.2A * 2.3V = 0.46W. 2) Estimate or measure the expected PCB temperature (Ts) at the solder pad. 3) Use Rth JS real (18 K/W): ΔT_junction = Power * Rth = 0.46W * 18 K/W ≈ 8.3K. 4) Junction Temp Tj = Ts + ΔT_junction. Ensure Tj < 150°C and preferably < 100°C for long life. Use the derating curve to check if your current is safe at your estimated Ts.

Q: Is a current-limiting resistor sufficient?
A: For simple, non-critical applications with a stable supply voltage (Vcc), a resistor can be used: R = (Vcc - VF_led) / I_F. Choose VF from the maximum bin (2.75V) to ensure current doesn't exceed limits if you get a low-VF LED. This method is inefficient and brightness will vary with Vcc and LED VF. A constant-current driver is recommended for automotive applications.

11. Design and Usage Case Study

Scenario: Designing a CHMSL (Center High-Mount Stop Light)
A designer needs 15 LEDs for a CHMSL. Requirements: High brightness for daytime visibility, consistent color, reliable operation from -40°C to +85°C ambient.
Design Steps: 1) Electrical: Choose a series configuration (all 15 LEDs in one string) to ensure identical current. A boost constant-current driver is selected to provide ~35V (15 * 2.3V) at 200mA. 2) Optical: Specify a tight dominant wavelength bin (e.g., 3033 or 3336) and a minimum luminous flux bin (F1 for highest output) to ensure color and brightness uniformity. 3) Thermal: The PCB is a 2-layer board with the top layer dedicated to large copper fills under each LED's thermal pad, connected with thick traces. Thermal vias connect to a bottom-layer copper plane. Thermal simulation is run to ensure the solder pad temperature stays below 80°C at maximum ambient temperature, keeping the junction temperature well within limits. 4) Layout: The recommended solder pad layout is used. ESD protection diodes are placed on the input power lines.

12. Operational Principle Introduction

Light Emitting Diodes (LEDs) are semiconductor devices that emit light through electroluminescence. When a forward voltage is applied across the p-n junction, electrons from the n-type region recombine with holes from the p-type region in the active layer. This recombination releases energy in the form of photons (light). The wavelength (color) of the emitted light is determined by the energy bandgap of the semiconductor materials used. For this Super Red LED, materials like AlInGaP (Aluminum Indium Gallium Phosphide) are typically used to achieve the 632 nm wavelength. The SMD package encapsulates the tiny semiconductor chip, provides mechanical protection, houses the primary lens that shapes the light output, and offers thermal and electrical connection paths via the lead frame.

13. Technology Trends and Context

The 2820 package represents a mature and widely adopted form factor in the industry, offering a good compromise between light output, thermal performance, and board space. Trends in automotive LED lighting include: Increased Efficiency: Ongoing development aims for higher lumens per watt (efficacy), reducing electrical load and thermal challenges. MiniaturizationSmart Lighting: Integration of control electronics or multiple color chips (RGB) into packages is growing. Higher Reliability Standards: Automotive standards like AEC-Q102 continue to evolve, pushing for longer lifetime predictions and robustness under more extreme conditions. This particular component, with its clear automotive focus and sulfur resistance, aligns with the industry's demand for components that can survive the increasingly harsh and long-life requirements of modern vehicles.