PLCC-4 Yellow LED Datasheet - Package 3.5x2.8x1.9mm - Forward Voltage 2.2V - Luminous Intensity 2300mcd - English Technical Document

1. Product Overview

This document details the specifications for a high-performance, surface-mount Yellow LED in a PLCC-4 (Plastic Leaded Chip Carrier) package. The device is engineered primarily for demanding automotive lighting applications, both interior and exterior. Its core advantages include a high typical luminous intensity of 2300 millicandelas (mcd) at a standard drive current of 50mA, a wide 120-degree viewing angle for excellent light dispersion, and robust construction meeting automotive-grade reliability standards.

The LED is qualified to the AEC-Q102 standard, ensuring its suitability for the harsh environmental conditions typical in automotive electronics. It also demonstrates sulfur robustness (Class A1), making it resistant to corrosion in atmospheres containing sulfur compounds. The product complies with key environmental regulations, including RoHS, EU REACH, and is manufactured as halogen-free.

2. In-Depth Technical Parameter Analysis

2.1 Optoelectronic Characteristics

The key performance metrics are defined under a standard test condition of a forward current (I_F) of 50mA. The typical luminous intensity (I_V) is 2300 mcd, with a specified minimum of 1800 mcd and a maximum of 4500 mcd. The dominant wavelength (λ_d) is centered at 591 nm (yellow), with a range from 585 nm to 594 nm, defining its precise color point. The forward voltage (V_F) typically drops 2.20V across the device at 50mA, with limits between 2.00V and 2.75V. The wide viewing angle (φ) of 120 degrees (±5° tolerance) is a critical parameter for applications requiring broad illumination rather than a focused beam.

2.2 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage may occur. The absolute maximum continuous forward current is 70 mA. The device can handle a surge current (I_FM) of 100 mA for pulses ≤10 μs at a very low duty cycle (D=0.005). The maximum power dissipation (P_d) is 192.5 mW. The junction temperature (T_J) must not exceed 125°C. The operating temperature range (T_opr) is from -40°C to +110°C, confirming its automotive-grade temperature resilience. The device is not designed for reverse bias operation.

2.3 Thermal Characteristics

Thermal management is crucial for LED performance and longevity. The datasheet specifies two thermal resistance values from the junction to the solder point: a real thermal resistance (R_{th JS real}) of 70 K/W (typical) and an electrical thermal resistance (R_{th JS el}) of 50 K/W (typical). The lower electrical value is derived from the temperature coefficient of the forward voltage and is used for in-situ junction temperature estimation. Proper PCB thermal design is necessary to keep the junction temperature within safe limits, especially at higher drive currents or elevated ambient temperatures.

3. Binning System Explanation

To ensure consistency in production, LEDs are sorted into performance bins. This allows designers to select parts that meet specific minimum criteria for their application.

3.1 Luminous Intensity Binning

LEDs are categorized into bins based on their minimum luminous intensity at the typical current. For example, bin 'BA' guarantees a minimum intensity of 1800 mcd, 'BB' guarantees 2240 mcd, and 'CA' guarantees 2800 mcd. Corresponding luminous flux values (in lumens) are provided for reference.

3.2 Dominant Wavelength Binning

Color consistency is controlled through wavelength bins. Bin '8588' covers LEDs with a dominant wavelength between 585 nm and 588 nm, '8891' covers 588-591 nm, and '9194' covers 591-594 nm. This ensures a tightly controlled yellow color output across production lots.

3.3 Forward Voltage Binning

Forward voltage is binned to aid in circuit design, particularly for current-limiting resistor calculation and power supply design. Bins include '1720' (1.75-2.00V), '2022' (2.00-2.25V), '2225' (2.25-2.50V), and '2527' (2.50-2.75V).

4. Performance Curve Analysis

The provided graphs offer deep insight into the LED's behavior under varying conditions.

4.1 IV Curve and Relative Intensity

The Forward Current vs. Forward Voltage graph shows the exponential relationship typical of a diode. The Relative Luminous Intensity vs. Forward Current graph demonstrates that light output increases sub-linearly with current, emphasizing the importance of stable current drive for consistent brightness.

4.2 Temperature Dependence

The Relative Luminous Intensity vs. Junction Temperature graph shows a negative temperature coefficient; light output decreases as the junction temperature rises. The Dominant Wavelength vs. Junction Temperature graph indicates a shift in color (typically towards longer wavelengths) with increasing temperature. The Relative Forward Voltage vs. Junction Temperature graph shows a negative coefficient, which is the principle used for the electrical method of junction temperature measurement.

4.3 Spectral Distribution and Derating

The Relative Spectral Distribution graph confirms the monochromatic yellow output, peaking around 591 nm with minimal emission in other bands. The Forward Current Derating Curve is critical for design: it dictates the maximum allowable continuous current based on the solder pad temperature (T_S). For instance, at a T_S of 110°C, the maximum continuous I_F is 57 mA. The Permissible Pulse Handling Capability graph defines the relationship between pulse width, duty cycle, and allowable peak pulse current.

5. Mechanical and Package Information

5.1 Mechanical Dimensions

The LED is housed in a standard PLCC-4 surface-mount package. The typical package dimensions are approximately 3.5mm in length, 2.8mm in width, and 1.9mm in height (including the dome). The datasheet includes a detailed dimensional drawing specifying all critical lengths, widths, and tolerances for PCB footprint design.

5.2 Recommended Soldering Pad Layout

A land pattern design is provided to ensure reliable soldering and optimal thermal performance. This includes the size, shape, and spacing of the copper pads on the PCB for the four leads and the central thermal pad (if applicable in this package variant). Following this recommendation is essential for mechanical stability and effective heat transfer from the LED junction to the PCB.

5.3 Polarity Identification

The PLCC-4 package has a specific orientation. The datasheet diagram indicates the cathode and anode pins. Typically, the package has a chamfered corner or a marking (like a dot) on the top to denote pin 1 (often the cathode). Correct orientation during assembly is mandatory for the device to function.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

A detailed reflow soldering temperature profile is specified to prevent thermal damage. The profile defines the preheat, soak, reflow, and cooling stages. A key parameter is the peak temperature, which must not exceed 260°C, and the time above 260°C should be limited to 30 seconds maximum. This profile is compatible with standard lead-free (SAC) solder pastes.

6.2 Precautions for Use

General handling precautions include avoiding mechanical stress on the epoxy lens, protecting the device from electrostatic discharge (ESD sensitivity is 2kV HBM), and ensuring that operating conditions (current, voltage, temperature) always remain within the absolute maximum ratings. The device should not be subjected to reverse voltage.

6.3 Storage Conditions

The recommended storage temperature range (T_stg) is from -40°C to +110°C. Components should be stored in a dry, anti-static environment in their original moisture-barrier bags, especially as they have a Moisture Sensitivity Level (MSL) of 2. This requires that the bag be opened and parts used within one year of the bag seal date, or they must be baked before reflow to prevent popcorning during soldering.

7. Packaging and Ordering Information

7.1 Packaging Specifications

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

7.2 Part Number Decoding

The part number 67-41-UY0501H-AM follows a specific structure:

• 67-41: Product family name.
• UY: Color code for Yellow.
• 050: Typical test current in mA (50mA).
• 1: Lead frame type (1=Gold).
• H: Brightness level (H=High).
• AM: Designates Automotive application.

This naming convention allows precise identification of the device's key attributes.

8. Application Recommendations

8.1 Typical Application Scenarios

The primary applications are in automotive lighting:

• Exterior Lighting: Daytime running lights (DRLs), side marker lights, center high-mount stop lights (CHMSL), and interior trunk/load area lighting.
• Interior Lighting: Dashboard backlighting, switch illumination, footwell lighting, door panel lights, and reading lights.

Its high brightness and wide viewing angle make it suitable for both functional illumination and aesthetic accent lighting.

8.2 Design Considerations

When designing with this LED:

• Current Drive: Always use a constant-current driver or a current-limiting resistor in series with a voltage source. Do not connect directly to a voltage source.
• Thermal Management:
Design the PCB with adequate copper area (thermal relief) connected to the LED's thermal pad/pins to dissipate heat. Use the derating curve to determine safe operating currents at expected ambient temperatures.
• Optics: The 120-degree viewing angle may require secondary optics (lenses, light guides) if a more focused beam is needed.
• ESD Protection: Implement standard ESD precautions during handling and assembly.

9. Technical Comparison and Differentiation

Compared to standard commercial-grade PLCC-4 LEDs, this device's key differentiators are its automotive qualifications. The AEC-Q102 certification involves rigorous testing for high-temperature operating life (HTOL), temperature cycling, moisture resistance, and other stressors, ensuring long-term reliability in vehicle environments. The specified sulfur robustness (Class A1) is another critical advantage for automotive use, where exposure to sulfur-containing gases from tires, fuels, or industrial atmospheres can corrode silver-based components in standard LEDs. The extended operating temperature range (-40°C to +110°C) also exceeds typical industrial ranges.

10. Frequently Asked Questions (FAQ)

Q: What is the difference between luminous intensity (mcd) and luminous flux (lm)?
A: Luminous intensity measures the brightness of a light source as perceived by the human eye in a specific direction (candelas). Luminous flux measures the total amount of visible light emitted by a source in all directions (lumens). This LED's datasheet provides intensity (mcd) as the primary metric, with flux (lm) given as a reference for the binned parts, as PLCC packages are often characterized by intensity.

Q: Why is a constant current driver recommended instead of a constant voltage?
A: An LED's forward voltage has a tolerance and varies with temperature. A constant voltage source with only a series resistor can lead to large variations in current, causing inconsistent brightness and potential overstress. A constant current source maintains a stable current, ensuring consistent light output and protecting the LED.

Q: How do I estimate the junction temperature in my application?
A> The electrical thermal resistance (R_{th JS el} = 50 K/W) can be used. Measure the forward voltage at a low sensing current at room temperature (calibration). Then, during operation at the drive current, momentarily switch to the low sensing current and measure the forward voltage again. The change in voltage, using the coefficient from the graph, allows calculation of the junction temperature rise: ΔT_J = ΔV_F / k, where k is the temperature coefficient of V_F.

11. Design and Usage Case Study

Case: Designing an Automotive Door Pocket Light
A designer needs a compact, reliable light for illuminating a car's door pocket. The light must be bright enough to be useful, have a wide beam to cover the pocket area, and survive the temperature extremes and vibrations inside a car door.
Solution: This PLCC-4 Yellow LED is selected. Its 120-degree viewing angle provides excellent coverage of the pocket without needing an additional diffuser. The typical 2300 mcd intensity is sufficient for a localized area light. The device is driven at 30mA (below the 50mA typical) using a simple current-limiting resistor circuit powered from the vehicle's 12V system, ensuring longevity and reducing thermal load. The AEC-Q102 qualification and sulfur robustness guarantee it will withstand the environment. The PLCC-4 package is soldered directly onto a small flexible PCB that fits into the door panel assembly.

12. Operational Principle

This is a semiconductor light-emitting diode. When a forward voltage exceeding its bandgap energy is applied, electrons and holes recombine in the active region of the semiconductor chip (typically based on materials like AlInGaP for yellow light). This recombination process releases energy in the form of photons (light). The specific wavelength of the yellow light (around 591 nm) is determined by the bandgap energy of the semiconductor material used in the chip's construction. The epoxy lens surrounding the chip serves to protect it, shape the light output beam (achieving the 120-degree angle), and enhance light extraction efficiency.

13. Technology Trends

In the automotive LED sector, key trends include:

• Increased Efficiency: Ongoing development of chip and package technology aims to deliver higher luminous efficacy (more lumens per watt), reducing power consumption and thermal load.
• Miniaturization: Packages continue to shrink while maintaining or increasing light output, enabling more compact and stylish lighting designs.
• Advanced Packaging: Use of materials with higher thermal conductivity and improved optical structures to manage heat and light more effectively.
• Smart Integration: Growth of LEDs with integrated drivers (IC-driven LEDs) or simple control interfaces for adaptive lighting applications.
• Color Consistency and Stability: Tighter binning specifications and improved phosphor technology (for white and converted colors) ensure consistent color output over temperature and lifetime, which is critical for automotive aesthetic and safety lighting.

This device, with its automotive-grade reliability and performance, aligns with the industry's demand for robust, high-quality components for both interior and exterior vehicle illumination.