Sky Blue PLCC-2 LED Datasheet - 3.1x2.8x1.9mm - 3.1V - 0.031W - English Technical Document

1. Product Overview

This document provides the complete technical specifications for a high-brightness Sky Blue LED in a PLCC-2 (Plastic Leaded Chip Carrier) surface-mount package. This component is designed for reliability and performance in demanding applications, featuring a typical luminous intensity of 300 millicandelas (mcd) at a forward current of 10mA. Its primary design targets include automotive interior environments and other applications requiring consistent color and stable output.

The LED's core advantages stem from its combination of a wide 120-degree viewing angle, making it suitable for area illumination, and its qualification to the AEC-Q101 standard, which is critical for automotive-grade components. It is also compliant with RoHS and REACH environmental directives. The device is offered with detailed binning information for both luminous intensity and chromaticity coordinates, allowing for precise selection in color-critical designs.

1.1 Target Market & Applications

The primary target market for this LED is the automotive electronics sector, specifically for interior lighting applications. Its reliability specifications make it suitable for integration into vehicle systems that must operate across a wide temperature range and withstand long-term use.

• Automotive Interior Lighting: Ideal for dashboard backlighting, ambient lighting, and indicator lights within the cabin.
• Switches: Can be used to illuminate mechanical or capacitive touch switches.
• Instrument Clusters: Suitable for backlighting gauges and displays where consistent blue illumination is required.

2. In-Depth Technical Parameter Analysis

The following section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters specified in the datasheet. Understanding these values is crucial for proper circuit design and thermal management.

2.1 Photometric & Optical Characteristics

The optical performance is defined under a standard test condition of a 10mA forward current (I_F) and a solder pad temperature of 25\u00b0C.

• Typical Luminous Intensity (I_V): 300 mcd. This is the central value, with a guaranteed minimum of 112 mcd and a maximum of 450 mcd for the standard product binning.
• Viewing Angle (2\u03b8_\u00bd): 120 degrees. This is the full angle at which the luminous intensity drops to half of its peak value. A tolerance of \u00b15 degrees is applicable.
• Typical Chromaticity Coordinates (CIE x, y): (0.16, 0.08). These coordinates define the specific shade of sky blue in the CIE 1931 color space. The tolerance for these coordinates is \u00b10.005.

2.2 Electrical Characteristics

• Forward Voltage (V_F): 3.1V typical at I_F=10mA, with a range from 2.75V (min) to 3.75V (max). This parameter has a measurement tolerance of \u00b10.05V. The V_F range represents a 99% output yield.
• Forward Current (I_F): The recommended continuous operating current is 10mA (typical). The absolute maximum rating is 20mA. A minimum current of 2mA is required for operation.
• Electrostatic Discharge (ESD) Sensitivity: Rated at 8 kV (Human Body Model, HBM). This indicates a moderate level of ESD robustness, but standard ESD handling precautions during assembly are still necessary.

2.3 Thermal Characteristics

• Thermal Resistance (R_thJS): Two values are provided. The real thermal resistance (junction to solder) is 120 K/W max, while the electrical method derived value is 95 K/W max. Designers should use the more conservative 120 K/W value for reliable thermal calculations.
• Junction Temperature (T_J): The maximum allowable temperature at the LED chip junction is 125\u00b0C.
• Operating Temperature Range (T_opr): -40\u00b0C to +110\u00b0C. This wide range is essential for automotive applications.

3. Absolute Maximum Ratings

Exceeding these limits may cause permanent damage to the device. They are not operating conditions.

• Power Dissipation (P_d): 75 mW
• Forward Current (I_F): 20 mA (DC)
• Surge Current (I_FM): 300 mA for pulses \u2264 10\u03bcs with a duty cycle (D) of 0.005 at 25\u00b0C.
• Reverse Voltage (V_R): The device is not designed for reverse operation. Applying a reverse voltage can cause immediate failure.
• Storage Temperature (T_stg): -40\u00b0C to +110\u00b0C.
• Reflow Soldering Temperature: Withstands 260\u00b0C for 30 seconds, which is compatible with standard lead-free (Pb-free) reflow profiles.

4. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins. This device uses two primary binning structures.

4.1 Luminous Intensity Binning

The luminous output is classified into groups denoted by an alphanumeric code (e.g., L1, R2, T1). Each bin defines a minimum and maximum luminous intensity in millicandelas (mcd). The bins follow a logarithmic progression, typically where the maximum of one bin is approximately 1.26 times (the fifth root of 10) its minimum. For this specific part number, the highlighted possible output bins center around the T1/T2 range (280-450 mcd), aligning with the 300 mcd typical value. The luminous flux measurement has a tolerance of \u00b18%.

4.2 Chromaticity Coordinate Binning (Sky Blue)

The color is defined within the CIE 1931 (x, y) chromaticity diagram. The datasheet shows a detailed bin structure chart for sky blue. The bins are labeled (e.g., JA1, JA2, JA11) and each is defined by four coordinate points forming a quadrilateral on the color chart. The typical coordinates (0.16, 0.08) fall within this structure. The tight tolerance of \u00b10.005 ensures minimal visual color variation between units from the same bin.

5. Performance Curve Analysis

The graphs provided illustrate how key parameters change with operating conditions, which is vital for dynamic design analysis.

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

This graph shows the exponential relationship typical of diodes. At 25\u00b0C, the voltage increases from approximately 2.9V at 5mA to about 3.3V at 25mA. This curve is essential for calculating the current-limiting resistor value and power dissipation in the LED.

5.2 Relative Luminous Intensity vs. Forward Current

The light output increases super-linearly with current. At 10mA, the relative intensity is defined as 1.0. It increases to about 2.2 at 25mA. This shows that driving the LED above the typical 10mA yields more light but also increases heat and reduces efficiency (lumens per watt).

5.3 Temperature Dependence

• Relative Luminous Intensity vs. Junction Temperature: The light output decreases as temperature rises. At the maximum junction temperature of 125\u00b0C, the output is roughly 40% of its value at 25\u00b0C. This significant drop must be accounted for in designs where the LED may operate at high ambient temperatures.
• Relative Forward Voltage vs. Junction Temperature: The forward voltage has a negative temperature coefficient, decreasing by about 2mV/\u00b0C. This can be used in some temperature-sensing circuits but is generally a secondary effect.
• Chromaticity Shift vs. Temperature/Current: The graphs show that the color coordinates (both x and y) shift slightly with changes in junction temperature and drive current. These shifts are typically within a few thousandths of a CIE unit and are usually not perceptible to the human eye but may be relevant in high-precision color-matching applications.

5.4 Spectral Distribution & Radiation Pattern

The relative spectral distribution graph shows a peak wavelength characteristic of a blue LED with a phosphor coating to produce the sky blue color, resulting in a broader emission spectrum than a pure blue chip. The radiation pattern diagram confirms the Lambertian-like emission profile with a 120-degree viewing angle.

5.5 Forward Current Derating & Pulse Handling

The derating curve mandates that the maximum allowable continuous forward current must be reduced as the solder pad temperature increases. At the maximum operating pad temperature of 110\u00b0C, the current must not exceed 20mA. The pulse handling capability graph shows that for very short duty cycles, the LED can withstand much higher peak currents (I_FP) than its DC rating.

6. Mechanical & Package Information

6.1 Mechanical Dimensions

The PLCC-2 package has a body size of approximately 3.1mm (length) x 2.8mm (width) x 1.9mm (height). Detailed drawings with tolerances are provided for the overall dimensions, lead spacing, and cavity details.

6.2 Recommended Soldering Pad Layout

A land pattern design is suggested for PCB layout to ensure reliable soldering and proper alignment. The pad dimensions are typically slightly larger than the device leads to facilitate good solder fillets.

6.3 Polarity Identification

The PLCC-2 package has a built-in polarity indicator. One corner of the device is chamfered or notched. The cathode (-) is typically located at this identified corner. The datasheet drawing clearly marks the anode and cathode.

7. Soldering & Assembly Guidelines

7.1 Reflow Soldering Profile

A recommended reflow profile is provided, conforming to standard lead-free (Pb-free) processes. The key parameter is a peak temperature of 260\u00b0C, which the device can withstand for up to 30 seconds. The preheat, soak, reflow, and cooling rates are specified to minimize thermal stress on the component.

7.2 Precautions for Use

• ESD Protection: Although rated for 8kV HBM, use standard ESD controls during handling and assembly.
• Current Limiting: Always use a series resistor or constant-current driver to limit the forward current to the desired value. Do not connect directly to a voltage source.
• Reverse Voltage Protection: Avoid applying any reverse bias. In circuits where reverse voltage is possible, incorporate a protection diode in series or parallel (with current limiting).
• Thermal Management: Ensure adequate PCB copper area or other heatsinking to keep the solder pad temperature within limits, especially when driving at higher currents or in high ambient temperatures.
• Cleaning: If cleaning is required after soldering, use compatible solvents that do not damage the plastic lens.

7.3 Moisture Sensitivity Level (MSL)

The device is rated MSL 2. This means it can be exposed to factory floor conditions (\u2264 30\u00b0C / 60% RH) for up to one year. If the sealed dry-pack bag is opened, the components must be soldered within a week, or they require baking before reflow to prevent popcorning damage.

8. Packaging & Ordering Information

8.1 Packaging Information

The LEDs are supplied on embossed carrier tape and reel for automated pick-and-place assembly. The datasheet specifies the tape width, pocket dimensions, reel diameter, and number of components per reel.

8.2 Part Number & Ordering Information

The part number system is not fully detailed in the excerpt, but it typically encodes key attributes like package type, color, brightness bin, and possibly color bin. Specific ordering would involve selecting the desired luminous intensity and chromaticity bins from the available options.

9. Application Design Considerations

9.1 Circuit Design

For basic operation with a constant voltage source (V_CC), calculate the series resistor (R_S) using: R_S = (V_CC - V_F) / I_F. Use the maximum V_F from the datasheet to ensure the minimum current is met under all conditions. For example, with a 5V supply and a desired I_F of 10mA: R_S = (5V - 3.75V) / 0.01A = 125\u03a9. Use the next standard value, 130\u03a9. The resistor power rating should be at least I_F² * R_S = 0.013W, so a 1/8W or 1/10W resistor is sufficient.

9.2 Thermal Design in Automotive Applications

In an automotive interior, ambient temperatures can easily reach 85\u00b0C. If the LED is mounted on a small PCB with limited copper, the solder pad temperature (T_S) could approach the ambient. From the derating curve, at T_S=85\u00b0C, the maximum allowed I_F is still above 20mA, so the 10mA drive is safe. However, if the LED is placed near other heat-generating components, the local temperature may be higher, necessitating a thermal analysis.

9.3 Optical Integration

The 120-degree viewing angle provides wide, even illumination. For applications requiring a more focused beam, an external secondary optic (lens) would be required. The plastic lens material may be sensitive to prolonged exposure to intense UV light, which is generally not a concern for interior applications.

10. Technical Comparison & Differentiation

Compared to generic non-automotive PLCC-2 LEDs, this device's key differentiators are its AEC-Q101 qualification and detailed, guaranteed binning structure. Many standard LEDs have looser tolerances on luminous intensity and color, which can lead to visible inconsistencies in a final product. The 8kV ESD rating is also higher than that of many basic commercial-grade LEDs. The wide operating temperature range (-40 to +110\u00b0C) specifically targets automotive requirements, whereas consumer LEDs often have a narrower range like -20 to +85\u00b0C.

11. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED at 20mA continuously?

A: Yes, but only if the solder pad temperature (T_S) is at or below 25\u00b0C. As T_S increases, the maximum allowable current decreases according to the derating curve. At a typical elevated temperature, a lower current like 10-15mA is safer for long-term reliability.

Q: The typical V_F is 3.1V, but my circuit measures 3.0V. Is this a problem?

A: No. The V_F has a range (2.75V to 3.75V) and a production distribution. A measurement of 3.0V is well within the specified minimum and typical values. Your actual luminous intensity might be slightly different than the typical curve predicts, but it will still be within the binning limits.

Q: Why is the luminous intensity specified at 10mA instead of the maximum 20mA?

A: 10mA is the standard test condition that ensures consistent measurement and comparison between different LEDs and manufacturers. It represents a common operating point that balances brightness, efficiency, and device longevity.

Q: How do I select the right bin for my application?

A: For applications where multiple LEDs are used side-by-side (e.g., a light bar), select a tight luminous intensity bin (e.g., T1 only) and a single chromaticity bin code to ensure uniform brightness and color. For single LED applications, a wider bin like T1/T2 may be acceptable and potentially more cost-effective.

12. Design-in Case Study

Scenario: Designing backlighting for an automotive center console switch panel. Four identical sky blue LEDs are needed to illuminate four buttons uniformly.

Design Steps:

1. Electrical Design: The vehicle supply is 12V nominal. Using a linear regulator to provide a stable 5V rail for the LEDs. For each LED: R_S = (5V - 3.75V) / 0.01A = 125\u03a9. Use 130\u03a9, 1/10W resistors. Total current draw: 4 * 10mA = 40mA.

2. Optical & Binning Selection: To ensure the four buttons look identical, order all LEDs from the same luminous intensity bin (e.g., T1: 280-355 mcd) and the same chromaticity bin (e.g., JA1). This minimizes unit-to-unit variation.

3. Thermal & Layout: The console interior may reach 80\u00b0C. The LEDs will be mounted on a small PCB. To keep T_S low, use a PCB with at least 1oz copper and connect the LED thermal pads to a small copper pour. The derating curve shows operation at 10mA is still safe at this temperature.

4. Validation: Build a prototype and measure light output and color at room temperature and after a thermal soak at 80\u00b0C. Verify that the intensity drop at high temperature is acceptable for the application.

13. Technology Principle Overview

This LED is based on semiconductor electroluminescence. A forward bias applied across the p-n junction causes electrons and holes to recombine, releasing energy in the form of photons. The base semiconductor material (typically InGaN) emits light in the blue spectrum. To achieve the sky blue color, the blue light from the chip is partially converted by a phosphor coating (often based on cerium-doped yttrium aluminum garnet or similar materials). The mixture of direct blue emission and down-converted broader spectrum light results in the final sky blue color point defined by the CIE coordinates. The PLCC-2 package provides a molded plastic lens that shapes the light output into the desired 120-degree radiation pattern and protects the semiconductor die and wire bonds.

14. Industry Trends

The market for SMD LEDs in automotive interiors continues to grow, driven by increased adoption of ambient lighting and fully digital instrument clusters. Trends include:

Higher Efficiency: Ongoing development aims to provide higher luminous intensity (mcd) at the same or lower drive currents, reducing power consumption and thermal load.

Color Tuning & Consistency: Demand for precise and consistent colors across multiple LEDs and over the product's lifetime is increasing, leading to tighter binning specifications and multi-channel programmable LED drivers.

Integration: There is a trend towards integrating multiple LED chips (e.g., RGB) into a single package or combining the LED with a driver IC for simplified design.

Reliability Focus: As LEDs become more critical in safety-adjacent applications (e.g., warning indicators), qualification standards like AEC-Q102 (the successor to AEC-Q101 for discrete optoelectronics) are becoming more stringent, requiring more comprehensive lifetime and stress testing data from suppliers.