LED Lamp 7343/Y5C2-ASVB/X/MS Datasheet - T-1 3/4 Package - 2.2V - 50mA - Brilliant Yellow - English Technical Document

1. Product Overview

This document details the specifications for a high-brightness LED lamp designed for applications requiring superior luminous output. The device utilizes AlGaInP chip technology to produce a brilliant yellow light. It is housed in a popular T-1 3/4 round package, offering a balance of performance and a familiar form factor for ease of integration into existing designs.

1.1 Core Advantages and Target Market

The primary advantages of this LED series include its high luminous intensity, reliable and robust construction, and availability in various viewing angles. The epoxy resin is UV resistant, enhancing long-term performance in outdoor environments. The product is compliant with relevant environmental regulations. It is supplied on tape and reel for automated assembly processes. The target applications are primarily in high-visibility signage, including color graphic signs, message boards, variable message signs (VMS), and commercial outdoor advertising, where clarity and brightness are paramount.

2. In-Depth Technical Parameter Analysis

A comprehensive analysis of the device's operational limits and performance under standard conditions.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. Operation under or at these limits is not guaranteed. Key parameters include a maximum reverse voltage (V_R) of 5V, a continuous forward current (I_F) of 50mA, and a peak forward current (I_FP) of 160mA under pulsed conditions (1/10 duty cycle @1kHz). The maximum power dissipation (P_d) is 115mW. The device is rated for an operating temperature range (T_opr) of -40\u00b0C to +85\u00b0C and a storage temperature range (T_stg) of -40\u00b0C to +100\u00b0C. It features Electrostatic Discharge (ESD) protection rated at 2000V (Human Body Model). The maximum soldering temperature is 260\u00b0C for 5 seconds.

2.2 Electro-Optical Characteristics

These characteristics are measured at a forward current of 20mA and an ambient temperature of 25\u00b0C, representing typical operating conditions. The luminous intensity (I_v) has a typical value of 9000 mcd, with a minimum of 5650 mcd and a maximum of 14250 mcd, indicating a high-brightness device. The viewing angle (2\u03b8_1/2) is typically 23 degrees, providing a focused beam. The peak wavelength (\u03bb_p) is 591 nm, and the dominant wavelength (\u03bb_d) is typically 589 nm, defining the brilliant yellow color. The spectral bandwidth (\u0394\u03bb) is 15 nm. The forward voltage (V_F) is typically 2.2V, with a range from 1.8V to 2.6V. The reverse current (I_R) is a maximum of 10 \u00b5A at 5V reverse bias.

3. Binning System Explanation

The devices are sorted into bins based on key performance parameters to ensure consistency within a production lot and allow for precise design matching.

3.1 Luminous Intensity Binning

Luminous intensity is categorized into four bins: S (5650-7150 mcd), T (7150-9000 mcd), U (9000-11250 mcd), and V (11250-14250 mcd). The tolerance for luminous intensity is \u00b110%. Designers must account for this range when calculating required drive currents or number of LEDs for a target brightness level.

3.2 Dominant Wavelength Binning

Dominant wavelength, which correlates with perceived color, is binned into two groups: Bin 1 (586-590 nm) and Bin 2 (590-594 nm). The tolerance is \u00b11 nm. This tight control is crucial for applications where color consistency across multiple LEDs is important, such as in full-color displays or signage.

3.3 Forward Voltage Binning

Forward voltage is divided into four bins: 1 (1.8-2.0V), 2 (2.0-2.2V), 3 (2.2-2.4V), and 4 (2.4-2.6V), with a tolerance of \u00b10.1V. Knowledge of the voltage bin is essential for designing efficient current-limiting circuits, especially when driving multiple LEDs in series, to ensure uniform current distribution and prevent thermal runaway.

4. Performance Curve Analysis

Graphical data provides insight into the device's behavior under varying conditions.

4.1 Spectral Distribution and Directivity

The Relative Intensity vs. Wavelength curve shows a narrow emission peak centered around 591 nm, confirming the monochromatic yellow output. The Directivity curve illustrates the spatial radiation pattern, with the 23-degree viewing angle corresponding to the half-intensity points. This pattern is important for optical design to achieve desired illumination profiles.

4.2 Current-Voltage (I-V) Relationship

The Forward Current vs. Forward Voltage curve is non-linear, typical of a diode. It shows the exponential increase in current after the forward voltage threshold is exceeded. This curve is critical for selecting appropriate drive circuitry (constant current vs. constant voltage).

4.3 Temperature Dependence

The Relative Intensity vs. Ambient Temperature curve demonstrates the negative temperature coefficient of luminous output; intensity decreases as ambient temperature rises. Conversely, the Forward Current vs. Ambient Temperature curve (at constant voltage) shows that current increases with temperature, which can lead to thermal runaway if not properly managed with a constant-current driver. These curves underscore the importance of thermal management in the system design.

5. Mechanical and Packaging Information

5.1 Package Dimensions

The device conforms to the standard T-1 3/4 round LED package dimensions. Critical measurements include the lead spacing, body diameter, and overall height. A note specifies that the maximum protrusion of resin under the flange is 1.5mm. All dimensions are in millimeters with a standard tolerance of 0.25mm unless otherwise specified. Precise dimensional data is essential for PCB footprint design and ensuring proper fit within mechanical enclosures.

5.2 Polarity Identification and Mounting

The cathode is typically indicated by a flat spot on the LED lens or a shorter lead. The datasheet emphasizes that during mounting, PCB holes must align exactly with the LED leads to avoid inducing mechanical stress, which can degrade the epoxy resin and LED performance.

6. Soldering and Assembly Guidelines

6.1 Lead Forming Precautions

If leads require bending, it must be done at a point at least 3mm from the base of the epoxy bulb to prevent stress on the internal die and wire bonds. Lead forming must be performed before soldering and at room temperature. Cutting leads at high temperatures can cause failure.

6.2 Soldering Parameters

For hand soldering, the iron tip temperature should not exceed 300\u00b0C (for a maximum 30W iron), and soldering time should be 3 seconds or less. For dip soldering, the recommended bath temperature is 260\u00b0C maximum for 5 seconds maximum, with a preheat up to 100\u00b0C for 60 seconds max. In both cases, the solder joint must be at least 3mm from the epoxy bulb. The soldering profile graph suggests a controlled ramp-up, soak, reflow, and cooling cycle to minimize thermal shock. Dip or hand soldering should not be performed more than once. Stress should not be applied to the leads while the LED is at high temperature.

6.3 Storage Conditions

LEDs should be stored at 30\u00b0C or less and 70% relative humidity or less. The recommended storage life after shipping is 3 months. For longer storage (up to one year), they should be kept in a sealed container with a nitrogen atmosphere and moisture-absorbent material. Rapid temperature transitions in high-humidity environments should be avoided to prevent condensation.

7. Packaging and Ordering Information

7.1 Packing Specification

LEDs are packed in anti-static bags to protect against ESD. These bags are placed in inner cartons, which are then packed into outside cartons. The packing quantity is flexible: a minimum of 200 to a maximum of 500 pieces per bag, 5 bags per inner carton, and 10 inner cartons per outside carton.

7.2 Label Explanation

The packaging label includes several codes: CPN (Customer's Product Number), P/N (Product Number), QTY (Packing Quantity), CAT (Ranks of Luminous Intensity and Forward Voltage), HUE (Rank of Dominant Wavelength), REF (Reference), and LOT No (Lot Number for traceability).

7.3 Model Numbering Rule

The part number 7343/Y5C2-ASVB/X/MS follows a specific structure. \"7343\" likely denotes the series or package type. \"Y5\" indicates the color (Yellow) and luminous intensity bin. \"C2\" may refer to the viewing angle or other optical characteristics. The \"ASVB\" segment could specify the chip technology or other features. The \"X\" is a placeholder for specific options (like stopper presence), and \"MS\" may indicate the packing style (e.g., tape and reel).

8. Application Recommendations

8.1 Typical Application Scenarios

This LED is ideally suited for high-ambient-light or long-viewing-distance applications due to its high luminous intensity. Primary uses include full-color or monochrome variable message signs on highways, advertising billboards, indoor/outdoor information displays, and status indicator panels where a distinct yellow signal is required.

8.2 Design Considerations

Driver Selection: Always use a constant-current driver to ensure stable light output and prevent thermal runaway, as the forward voltage has a negative temperature coefficient. The driver should be rated for the maximum forward current (50mA continuous).
Thermal Management: Despite the low power dissipation (115mW max), proper PCB layout with adequate copper area for heat sinking is recommended, especially when operating at high ambient temperatures or at the upper end of the current range, to maintain luminous intensity and longevity.
Optical Design: The 23-degree viewing angle produces a relatively focused beam. For wider illumination, secondary optics (lenses or diffusers) may be required. The UV-resistant epoxy allows for reliable outdoor use without significant lens yellowing.

9. Technical Comparison and Differentiation

Compared to standard yellow LEDs, this device's key differentiator is its very high luminous intensity (up to 14250 mcd @ 20mA), which is achieved through advanced AlGaInP chip technology and optimized package design. The availability of tight binning for intensity, wavelength, and voltage allows for superior color and brightness uniformity in array applications compared to unbinned or loosely binned products. The T-1 3/4 package offers a proven, reliable mechanical format with good heat dissipation characteristics relative to smaller surface-mount packages, making it robust for demanding environments.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED with a 3.3V supply and a resistor?
A: Yes, but careful calculation is needed. With a typical V_F of 2.2V, a series resistor would drop 1.1V. To achieve 20mA, the resistor value would be R = V/I = 1.1V / 0.02A = 55\u03a9. However, you must consider the voltage bin (1.8V to 2.6V). For a 2.6V LED, the resistor drops only 0.7V, resulting in a current of 0.7V / 55\u03a9 \u2248 12.7mA, reducing brightness. A constant-current driver is more reliable.

Q: What is the difference between peak wavelength and dominant wavelength?
A: Peak wavelength (\u03bb_p) is the wavelength at which the emission spectrum has its maximum intensity (591 nm here). Dominant wavelength (\u03bb_d) is the single wavelength of monochromatic light that matches the perceived color of the LED (typically 589 nm here). Dominant wavelength is more relevant for color specification.

Q: How does the viewing angle affect my design?
A: A 23-degree viewing angle (full width at half maximum) means the light is concentrated within a relatively narrow cone. For a sign intended to be viewed from a wide angle, you may need to space LEDs closer together or use a diffuser to create a more uniform appearance. For a long-throw application, this focused beam is advantageous.

11. Practical Design and Usage Case

Case: Designing a High-Visibility Warning Beacon.
A designer needs a flashing yellow beacon for a construction vehicle. They select this LED for its high intensity and robust package. They design a PCB with a 55\u03a9 current-limiting resistor per LED, powered from the vehicle's 12V system. To achieve the necessary brightness across all voltage bins, they use a PWM circuit to drive the LED at an average current of 20mA. The LED is mounted in a reflector to further collimate the 23-degree beam for maximum long-distance visibility. The UV-resistant epoxy ensures the lens does not degrade under prolonged sun exposure. The storage and soldering guidelines are followed during assembly to guarantee reliability in the harsh vehicular environment with wide temperature swings.

12. Operating Principle Introduction

This LED is a semiconductor light source based on an AlGaInP (Aluminum Gallium Indium Phosphide) chip. When a forward voltage exceeding the diode's threshold is applied, electrons and holes recombine in the active region of the semiconductor, releasing energy in the form of photons. The specific composition of the AlGaInP alloy determines the bandgap energy, which directly corresponds to the wavelength (color) of the emitted light\u2014in this case, yellow (~589 nm). The high brightness is achieved through efficient internal quantum efficiency and effective light extraction from the chip and package. The epoxy lens serves to protect the chip, shape the beam (23-degree viewing angle), and enhance light output.

13. Technology Trends

The trend in LED technology for signage and high-brightness applications continues towards higher efficacy (more lumens per watt), improved color consistency through tighter binning, and enhanced reliability. While this device uses a proven through-hole package, the industry is broadly moving towards surface-mount device (SMD) packages for automated assembly and higher density. However, through-hole packages like the T-1 3/4 remain relevant for applications requiring superior thermal performance, mechanical robustness, or easy field replacement. Advances in phosphor-converted and direct-color semiconductor materials may offer alternative pathways to specific colors with potentially higher efficiency or different spectral characteristics in the future.