LED Lamp 264-7UYD/S530-A3 Specification - Brilliant Yellow - 20mA - 125mcd - English Technical Document

1. Product Overview

This document provides the complete technical specifications for a high-brightness, 5mm brilliant yellow LED lamp. Designed for reliability and performance, this component is suitable for a variety of indicator and backlighting applications in consumer electronics. The LED features a diffused yellow epoxy resin lens that provides a wide, uniform viewing angle.

1.1 Core Advantages and Target Market

The primary advantages of this LED series include higher brightness output and a choice of various viewing angles to suit different application needs. It is available on tape and reel for automated assembly, enhancing production efficiency. The product is compliant with RoHS directives and is lead-free. Its robust design ensures reliable operation. The target applications are primarily within the consumer electronics sector, including use in television sets, computer monitors, telephones, and general computing equipment where clear, bright status indication is required.

2. In-Depth Technical Parameter Analysis

This section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters defined in the datasheet.

2.1 Absolute Maximum Ratings

The Absolute Maximum Ratings define the stress limits beyond which permanent damage to the device may occur. These are not recommended operating conditions.

• Continuous Forward Current (IF): 25 mA. Exceeding this current, especially without proper heat sinking, can lead to rapid degradation of the LED's internal quantum well and a permanent reduction in light output.
• Peak Forward Current (IFP): 60 mA (at a duty cycle of 1/10 and 1 kHz). This rating allows for short pulses of higher current, which can be useful for multiplexing circuits or achieving momentary peak brightness. Continuous operation at or near this current is prohibited.
• Reverse Voltage (VR): 5 V. Applying a reverse bias voltage greater than this can cause a sudden, catastrophic breakdown of the LED's PN junction.
• Power Dissipation (Pd): 60 mW. This is the maximum power the package can dissipate as heat. The actual power dissipated is VF * IF. At the typical forward voltage of 2.0V and maximum continuous current of 25mA, the power is 50mW, leaving a small safety margin.
• Operating & Storage Temperature: -40°C to +85°C and -40°C to +100°C, respectively. These ranges define the environmental limits for reliable operation and non-operational storage.
• Soldering Temperature: 260°C for 5 seconds. This defines the maximum thermal profile the LED package can withstand during wave or reflow soldering processes.

2.2 Electro-Optical Characteristics

These parameters are measured under standard test conditions (Ta=25°C, IF=20mA) and define the device's typical performance.

• Luminous Intensity (Iv): 63 mcd (Min), 125 mcd (Typ). This is the measure of perceived brightness to the human eye. The typical value of 125 mcd indicates a high-brightness output for a standard 5mm LED. The minimum guaranteed value is 63 mcd.
• Viewing Angle (2θ1/2): 60° (Typical). This is the full angle at which the luminous intensity drops to half of its peak value (on-axis). A 60° angle provides a good balance between a focused beam and wide visibility.
• Peak Wavelength (λp): 591 nm (Typical). This is the wavelength at which the spectral power distribution of the emitted light is maximum. For a brilliant yellow LED, this falls in the yellow-orange region of the visible spectrum.
• Dominant Wavelength (λd): 589 nm (Typical). This is the single wavelength perceived by the human eye that best matches the color of the LED. It is the key parameter for color specification.
• Forward Voltage (VF): 1.7V (Min), 2.0V (Typ), 2.4V (Max) at 20mA. The forward voltage has a negative temperature coefficient (decreases as temperature increases). Circuit designs must account for the variation from 1.7V to 2.4V to ensure proper current regulation.
• Reverse Current (IR): 10 μA (Max) at VR=5V. A small leakage current is normal. Exceeding the maximum reverse voltage will cause this current to increase dramatically.

3. Performance Curve Analysis

The datasheet provides several characteristic curves that are essential for understanding the LED's behavior under different operating conditions.

3.1 Relative Intensity vs. Wavelength

This spectral distribution curve shows the light output as a function of wavelength. For this brilliant yellow LED, the curve will have a single, distinct peak centered around 591 nm (typical) with a typical spectral bandwidth (Δλ) of 15 nm. This indicates a relatively pure yellow color without significant emission in other color bands.

3.2 Directivity Pattern

The directivity (or radiation pattern) curve illustrates how light intensity varies with angle from the central axis. The typical 60° viewing angle (2θ1/2) means the intensity is 50% of its on-axis value at ±30° from the center. The shape of this curve is influenced by the diffused epoxy lens, which scatters light to create a more uniform viewing cone compared to a clear lens.

3.3 Forward Current vs. Forward Voltage (IV Curve)

This curve shows the exponential relationship between forward voltage (VF) and forward current (IF). For a typical LED, a small increase in voltage beyond the turn-on threshold (around 1.7V for this device) causes a large increase in current. This is why LEDs are almost always driven by a constant current source, not a constant voltage source, to prevent thermal runaway.

3.4 Relative Intensity vs. Forward Current

This graph demonstrates that light output (luminous intensity) is approximately proportional to forward current in the normal operating range (e.g., up to 20-25mA). However, efficiency (lumens per watt) may decrease at very high currents due to increased heat generation.

3.5 Temperature Dependence Curves

Relative Intensity vs. Ambient Temperature: The light output of an LED decreases as the junction temperature increases. This curve quantifies that derating. For AlGaInP-based yellow LEDs, the output can drop significantly at high temperatures (e.g., above 60-70°C).
Forward Current vs. Ambient Temperature: This curve likely shows the maximum allowable forward current as a function of ambient temperature to stay within the power dissipation (Pd) limit. As ambient temperature rises, the maximum safe operating current must be reduced to prevent the junction temperature from exceeding its maximum rating.

4. Mechanical and Package Information

4.1 Package Dimensions

The LED is housed in a standard 5mm radial leaded package. Key dimensional notes from the datasheet include: All dimensions are in millimeters (mm). The height of the flange (the flat rim at the base of the dome) must be less than 1.5mm. Unless otherwise specified, the general tolerance for dimensions is ±0.25mm. The detailed drawing shows the lead spacing, body diameter, total height, and lead length and diameter, which are critical for PCB footprint design and assembly.

4.2 Polarity Identification

For radial leaded LEDs, the cathode is typically identified by a flat spot on the rim of the plastic lens and/or by the shorter lead length. The datasheet's dimensional drawing should clearly indicate which lead is the cathode. Correct polarity must be observed during circuit assembly.

5. Soldering and Assembly Guidelines

Proper handling is crucial to maintain LED performance and reliability.

5.1 Lead Forming

• Bend leads at a point at least 3mm from the base of the epoxy bulb.
• Perform lead forming before soldering.
• Avoid applying stress to the LED package or its base during bending.
• Cut leads at room temperature, not when hot.
• Ensure PCB holes align perfectly with LED leads to avoid mounting stress.

5.2 Storage Conditions

• Store at ≤30°C and ≤70% Relative Humidity (RH) upon receipt. Shelf life under these conditions is 3 months.
• For longer storage (up to 1 year), use a sealed container with a nitrogen atmosphere and desiccant.
• Avoid rapid temperature changes in humid environments to prevent condensation.

5.3 Soldering Process

General Rule: Maintain a minimum distance of 3mm from the solder joint to the epoxy bulb.
Hand Soldering: Iron tip temperature: 300°C Max (30W iron max). Soldering time: 3 seconds Max per lead.
Wave/Dip Soldering: Preheat temperature: 100°C Max (60 sec Max). Solder bath temperature: 260°C Max. Dwell time in solder: 5 seconds Max.
Profile: A recommended soldering temperature profile is provided, emphasizing a controlled ramp-up, peak temperature hold, and controlled cooldown. A rapid cooldown process is not recommended.
Important: Avoid stress on leads during high-temperature phases. Do not solder the device more than once via dip or hand soldering methods. Protect the LED from mechanical shock until it returns to room temperature after soldering.

5.4 Cleaning

If cleaning is necessary, use isopropyl alcohol at room temperature for no more than one minute. Dry at room temperature. Ultrasonic cleaning is generally not recommended. If absolutely required, its parameters (power, time) must be pre-qualified to ensure no damage occurs.

5.5 Heat Management

Proper thermal management is essential for LED longevity and stable light output. The current should be de-rated appropriately at higher ambient temperatures, as indicated by the derating curve. During the application design phase, consider the LED's power dissipation and ensure adequate heat sinking or airflow if operating near maximum ratings.

6. Packaging and Ordering Information

6.1 Packing Specification

The LEDs are packed in moisture-resistant, anti-static materials to protect them from electrostatic discharge (ESD) and humidity. The packing hierarchy is as follows: LEDs are placed in anti-static bags. A minimum of 200 to 1000 pieces are packed per bag. Four bags are placed into one inner carton. Ten inner cartons are packed into one master (outside) carton.

6.2 Label Explanation

Labels on the packaging contain key information: CPN (Customer's Part Number), P/N (Manufacturer's Part Number: 264-7UYD/S530-A3), QTY (Packing Quantity), CAT (Ranks/Bin), HUE (Dominant Wavelength), REF (Reference), and LOT No (Lot Number for traceability).

7. Application Notes and Design Considerations

7.1 Typical Application Circuits

LEDs require current limiting. The simplest method is a series resistor. The resistor value (R) is calculated as: R = (Vsupply - VF) / IF. For example, with a 5V supply, a typical VF of 2.0V, and a desired IF of 20mA: R = (5V - 2.0V) / 0.020A = 150 Ohms. The resistor power rating should be at least (5V-2.0V)*0.020A = 0.06W (a 1/8W or 1/4W resistor is suitable). For precision or stability, a constant current driver circuit is recommended.

7.2 Design Considerations

• Current Drive: Always use a constant current source or a current-limiting resistor. Never connect directly to a voltage source.
• Voltage Variation: Account for the forward voltage range (1.7V to 2.4V) in your design to ensure the desired current is delivered across all units.
• Thermal Design: For applications with high ambient temperature or continuous operation at high current, consider the thermal derating. Provide adequate spacing on the PCB or use a heatsink if necessary.
• ESD Protection: Although not extremely sensitive, standard ESD handling precautions should be observed during assembly.

8. Technical Comparison and Differentiation

This brilliant yellow LED, based on AlGaInP semiconductor material, offers distinct advantages. Compared to older technology yellow LEDs (e.g., based on GaAsP), AlGaInP provides significantly higher luminous efficiency, resulting in greater brightness for the same drive current. The 125 mcd typical intensity is competitive for a standard 5mm package. The wide 60° viewing angle achieved through a diffused lens makes it suitable for applications requiring broad visibility, as opposed to focused beam applications which might use a clear lens with a narrower angle. Its RoHS compliance and lead-free construction align with modern environmental regulations.

9. Frequently Asked Questions (FAQs)

Q: Can I drive this LED at 30mA for more brightness?
A: No. The Absolute Maximum Rating for continuous forward current is 25 mA. Operating at 30 mA exceeds this rating, which will significantly reduce the LED's lifespan and may cause immediate failure due to overheating.

Q: The forward voltage of my LED measures 1.8V, not the typical 2.0V. Is this normal?
A: Yes. The datasheet specifies a range from 1.7V (Min) to 2.4V (Max) at 20mA. A value of 1.8V is well within the specified range and is acceptable. Your current-limiting circuit should be designed to accommodate this entire range.

Q: How do I identify the cathode?
A> Look for two physical indicators: 1) The shorter lead is usually the cathode. 2) There is often a flat spot on the rim of the round plastic lens; the lead nearest to this flat spot is the cathode.

Q: Can I use this LED outdoors?
A: The operating temperature range is -40°C to +85°C, which covers most outdoor environments. However, you must ensure the LED is properly sealed and protected from direct exposure to water and UV radiation, which can degrade the epoxy resin over time. The drive current may also need to be derated in high-temperature ambient conditions.

10. Practical Application Example

Scenario: Designing a status indicator panel for a piece of test equipment.
Requirement: Multiple yellow LEDs to indicate "Standby" or "Caution" states. The panel will be viewed from various angles up to 30 degrees off-axis. The supply voltage is a regulated 3.3V.
Design Steps:
1. LED Selection: This brilliant yellow LED with a 60° viewing angle is a good fit, ensuring visibility across the required viewing cone.
2. Current Setting: Choose a drive current of 20mA for a good balance of brightness and longevity.
3. Resistor Calculation: Use the maximum VF (2.4V) for a worst-case design to guarantee the current never exceeds 20mA. R = (3.3V - 2.4V) / 0.020A = 45 Ohms. The nearest standard value is 47 Ohms.
4. Recalculate Actual Current: With a typical VF of 2.0V, IF = (3.3V - 2.0V) / 47 Ohms ≈ 27.7 mA. This is above the 25mA maximum. Therefore, to safely cover the entire VF range, use the minimum VF to check the upper limit: IF_max = (3.3V - 1.7V) / 47 Ohms ≈ 34 mA. This is too high.
5. Revised Calculation: Design for the typical case and add a small margin. Use VF_typ = 2.0V. R = (3.3V - 2.0V) / 0.020A = 65 Ohms. Nearest standard is 68 Ohms. Check: IF_min = (3.3V-2.4V)/68≈13.2mA, IF_typ≈19.1mA, IF_max=(3.3V-1.7V)/68≈23.5mA. This keeps the maximum possible current just under the 25mA limit, making 68 Ohms a safe and appropriate choice.
6. PCB Layout: Follow the package dimensions for the hole spacing. Ensure the cathode (identified by the flat on the LED and the shorter lead) is connected to the ground side of the circuit.