PLCC-2 Sky Blue LED Datasheet - Package 3.2x2.8x1.9mm - Voltage 2.9V - Power 75mW - English Technical Document

1. Product Overview

This document details the specifications for a high-brightness, Sky Blue LED in a PLCC-2 (Plastic Leaded Chip Carrier) surface-mount package. The device is engineered for reliability and performance in demanding environments, featuring a wide 120-degree viewing angle and qualification to the AEC-Q101 standard for automotive components. Its primary applications include automotive interior ambient lighting, backlighting for switches and indicators, and other general illumination purposes where consistent color and brightness are required.

1.1 Core Advantages

• High Luminance Efficiency: Delivers a typical luminous intensity of 355 millicandelas (mcd) at a standard drive current of 10mA, ensuring bright and visible output.
• Wide Viewing Angle: The 120-degree viewing angle provides uniform light distribution, ideal for panel lighting and indicators.
• Automotive Grade: AEC-Q101 qualification ensures reliability under the harsh conditions typical in automotive applications, including wide temperature ranges and vibration.
• Environmental Compliance: The product is compliant with RoHS (Restriction of Hazardous Substances) and REACH regulations, supporting environmentally conscious manufacturing.
• Robust ESD Protection: Withstands Electrostatic Discharge (ESD) up to 8kV (Human Body Model), enhancing handling and assembly reliability.

2. In-Depth Technical Parameter Analysis

2.1 Photometric and Color Characteristics

The LED's core performance is defined by its photometric and colorimetric parameters, measured under standard conditions (T_s=25°C, I_F=10mA unless specified).

• Typical Luminous Intensity (I_V): 355 mcd. This is the primary measure of brightness. The minimum and maximum values under standard test conditions are 140 mcd and 560 mcd, respectively, indicating the production spread.
• Color Coordinates (CIE x, y): The typical chromaticity coordinates are (0.16, 0.08), which defines the specific shade of Sky Blue. The tolerance for these coordinates is ±0.005, ensuring tight color consistency between units.
• Viewing Angle (φ): 120 degrees. This is the full angle at which the luminous intensity drops to half of its peak value (often denoted as 2θ_1/2). A tolerance of ±5 degrees applies.

2.2 Electrical and Thermal Parameters

• Forward Voltage (V_F): Typically 2.90V at 10mA, with a range from 2.75V (Min) to 3.75V (Max). This parameter is crucial for designing the current-limiting circuitry.
• Forward Current (I_F): The recommended continuous operating current is 10mA (Typ.), with an absolute maximum rating of 20mA. A minimum current of 2mA is required for operation.
• Power Dissipation (P_d): The maximum allowable power dissipation is 75 mW, which dictates the thermal management requirements.
• Thermal Resistance: Two values are provided: R_{th JS(el)} (electrical model) is 125 K/W max, and R_{th JS(real)} (real condition) is 200 K/W max. These values describe how effectively heat travels from the LED junction to the solder point.

2.3 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage may occur. Operation under these conditions is not guaranteed.

• Junction Temperature (T_J): 125 °C
• Operating/Storage Temperature (T_opr/T_stg): -40 °C to +110 °C
• Reverse Voltage (V_R): The device is not designed for reverse bias operation.
• Surge Current (I_FM): 300 mA for pulses ≤10μs with a low duty cycle (D=0.005).
• Soldering Temperature: Withstands 260°C for 30 seconds during reflow soldering.

3. Performance Curve Analysis

3.1 Spectral and Radiation Distribution

The Relative Spectral Distribution graph shows a narrow peak in the blue wavelength region, characteristic of a blue LED with a phosphor coating to produce the sky blue color. The Typical Diagram of Radiation Characteristics illustrates the Lambertian-like emission pattern, confirming the wide 120-degree viewing angle with smooth intensity fall-off.

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

This graph shows the exponential relationship typical of a diode. The curve allows designers to determine the precise voltage drop for a given drive current, which is essential for calculating power consumption and selecting appropriate driver components.

3.3 Relative Luminous Intensity vs. Forward Current

The light output increases super-linearly with current before potentially saturating at higher currents. This curve is vital for understanding efficiency and for pulse-width modulation (PWM) dimming design, where average current controls brightness.

3.4 Temperature Dependence

Several graphs detail performance changes with temperature:

• Relative Forward Voltage vs. Junction Temperature: Shows V_F decreases linearly with increasing temperature (negative temperature coefficient), which can be used for temperature sensing.
• Relative Luminous Intensity vs. Junction Temperature: Demonstrates that light output decreases as temperature rises, a critical factor for thermal management in high-brightness or enclosed applications.
• Chromaticity Shift vs. Junction Temperature: Plots the change in CIE x and y coordinates, showing minimal shift, which is important for applications requiring stable color over temperature.

3.5 Derating and Pulse Handling

The Forward Current Derating Curve dictates how the maximum allowable continuous current must be reduced as the solder pad temperature increases above 25°C. The Permissible Pulse Handling Capability graph defines the peak current (I_F) allowed for very short pulse widths (t_p) at various duty cycles, useful for strobe or multiplexing applications.

4. Binning System Explanation

To manage production variations, LEDs are sorted into bins based on key parameters.

4.1 Luminous Intensity Binning

A comprehensive binning structure is defined with codes from L1 to GA. Each bin specifies a minimum and maximum luminous intensity (mcd) range. For example, bin T1 covers 280 to 355 mcd, and T2 covers 355 to 450 mcd. The typical part (355 mcd) falls at the lower boundary of the T2 bin. Designers must specify the required bin when ordering to ensure brightness consistency in their application.

4.2 Color Binning

The datasheet references a \"Standard Sky Blue Color Bin Structure\" (the specific CIE chart is not fully detailed in the provided excerpt). Typically, this would be a defined region on the CIE 1931 chromaticity diagram within which the LED's (x, y) coordinates must fall. The tight tolerance of ±0.005 ensures all units within a color bin are visually matched.

5. Mechanical and Package Information

5.1 Mechanical Dimensions

The LED uses a standard PLCC-2 surface-mount package. Key dimensions (in millimeters) typically include the body size (e.g., 3.2mm x 2.8mm), height (e.g., 1.9mm), and lead spacing. Precise dimensional drawings are essential for PCB footprint design.

5.2 Recommended Solder Pad Layout

A land pattern design is provided to ensure reliable soldering and proper thermal dissipation. Following this recommendation prevents tombstoning, misalignment, and ensures a strong mechanical and electrical connection.

5.3 Polarity Identification

The PLCC-2 package has a built-in polarity indicator, usually a notch or a chamfered corner on the body. The cathode (negative) lead is typically identified by this marker. Correct orientation is crucial for circuit operation.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

A detailed temperature-time profile is specified for reflow soldering. Key parameters include:

• Peak Temperature: 260°C maximum.
• Time Above Liquidus (TAL): Typically 30-60 seconds within a specified range (e.g., 217-260°C).
• Ramp-Up and Ramp-Down Rates: Controlled to prevent thermal shock to the component.

Adhering to this profile is critical to avoid damaging the LED or compromising its long-term reliability.

6.2 Precautions for Use

• ESD Precautions: Handle using ESD-safe procedures and equipment, as the device is sensitive to electrostatic discharge.
• Current Limiting: Always use a series resistor or constant-current driver to limit forward current to the specified value. Do not connect directly to a voltage source.
• Thermal Management: Ensure adequate PCB copper area or heatsinking, especially when operating at high currents or in elevated ambient temperatures, to keep the junction temperature within limits.
• Cleaning: Use appropriate cleaning solvents that are compatible with the LED package material.

7. Packaging and Ordering Information

7.1 Packaging Specifications

The LEDs are supplied on tape and reel for automated assembly. Standard reel quantities (e.g., 2000 or 4000 pieces per reel) and tape dimensions are specified to be compatible with standard pick-and-place equipment.

7.2 Part Number Structure

The part number 57-11-SB0100L-AM encodes specific attributes:

• 57-11: Likely denotes the product series or package type (PLCC-2).
• SB: Indicates Sky Blue color.
• 0100L: May relate to brightness bin or specific performance grade.
• AM: Could indicate automotive grade or a specific revision.

Consult the full ordering guide to select the correct bin codes for intensity and color.

8. Application Notes and Design Considerations

8.1 Typical Application Circuits

The most basic drive circuit is a voltage source (V_CC) in series with a current-limiting resistor (R_S) and the LED. The resistor value is calculated as: R_S = (V_CC - V_F) / I_F. For example, with a 5V supply and a target I_F of 10mA: R_S = (5V - 2.9V) / 0.01A = 210 Ω. A 210Ω or nearest standard value (220Ω) resistor would be used. For better stability and efficiency, especially in automotive applications, a constant-current driver IC is recommended.

8.2 Design for Automotive Environments

• Voltage Transients: The vehicle's electrical system experiences load dumps and other transients. Ensure the driver circuit includes protection (e.g., TVS diodes, robust regulators) to keep the LED voltage/current within spec.
• Temperature Cycling: Design the PCB and assembly to withstand thermal expansion/contraction stresses from -40°C to +110°C.
• Vibration Resistance: A robust solder joint, achieved by following the recommended pad layout and reflow profile, is essential.

8.3 Dimming Techniques

Brightness can be controlled via:

• Pulse-Width Modulation (PWM): The preferred method. Switching the LED on/off at a frequency high enough to be imperceptible to the eye (typically >100Hz). The average current, and thus brightness, is proportional to the duty cycle. This method maintains consistent color.
• Analog Dimming: Reducing the DC drive current. This is simpler but can cause a slight shift in color coordinates and forward voltage, as shown in the characteristics graphs.

9. Frequently Asked Questions (FAQ)

9.1 What is the difference between luminous intensity (mcd) and luminous flux (lm)?

Luminous intensity measures brightness in a specific direction (candelas), while luminous flux measures the total visible light emitted in all directions (lumens). This LED's datasheet specifies intensity because it is a directional source with a defined viewing angle. Flux can be estimated but is not the primary specified metric for this component type.

9.2 Can I drive this LED at 20mA continuously?

While the absolute maximum rating is 20mA, continuous operation at this current requires careful thermal management to ensure the junction temperature does not exceed 125°C. The derating curve must be consulted based on the actual solder pad temperature. For reliable long-term operation, driving at or near the typical 10mA is recommended.

9.3 How do I interpret the binning codes when ordering?

You must specify both a luminous intensity bin (e.g., T1, T2) and a color bin code. The exact color bin codes and their corresponding CIE regions are defined in the full binning information. Ordering by part number alone may yield a default bin; for consistent results across production batches, explicitly specifying the required bins is necessary.

9.4 Is a heatsink required?

For low-current operation (e.g., 10mA) in moderate ambient temperatures, the thermal path through the PCB pads is often sufficient. For higher currents, high ambient temperatures, or when multiple LEDs are placed closely, adding thermal vias under the pad or increasing the copper area on the PCB acts as an effective heatsink. In extreme cases, a dedicated metal-core PCB may be required.