Through Hole LED Lamp T-1 3mm Specification - Blue & Red with White Diffuser - Voltage 2.9V/1.9V - Power 70mW/52mW - English Technical Document

1. Product Overview

This document details the specifications for a through-hole LED indicator lamp. The device is offered in a popular T-1 (3mm) diameter package and is characterized by its combination of a blue or red LED chip with a white diffuser lens. This design choice aims to provide a uniform, diffused light output suitable for status indication across various applications.

1.1 Core Features and Advantages

The primary advantages of this LED lamp include its low power consumption and high efficiency, making it suitable for battery-powered or energy-conscious designs. It is constructed with lead-free materials and is compliant with RoHS environmental directives. The T-1 form factor is a widely adopted industry standard, ensuring compatibility with existing PCB layouts and manufacturing processes. The integration of a white diffuser lens over the colored chip helps to soften and spread the light, reducing glare and creating a more aesthetically pleasing indicator.

1.2 Target Applications and Markets

This component is designed for general-purpose status indication. Its typical application domains include communication equipment (e.g., routers, modems), computer peripherals, consumer electronics, and home appliances. The reliability and simplicity of the through-hole design make it a common choice for applications requiring clear, durable visual feedback.

2. In-Depth Technical Parameter Analysis

This section provides a detailed, objective interpretation of the key electrical, optical, and thermal parameters that define the device's performance envelope.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. They are not intended for normal operation.

• Power Dissipation (Pd): Blue: 70 mW, Red: 52 mW. This parameter, dependent on the chip technology, dictates the maximum thermal energy the package can handle at 25°C ambient.
• Forward Current: Continuous DC forward current is rated at 20 mA for both colors. A higher peak forward current of 60 mA is permissible under pulsed conditions (duty cycle ≤ 1/10, pulse width ≤ 10 µs).
• Temperature Ranges: The operating temperature range is -30°C to +85°C. The storage range is wider, from -40°C to +100°C.
• Soldering Temperature: Leads can withstand 260°C for a maximum of 5 seconds when measured 2.0mm from the LED body.

2.2 Electrical & Optical Characteristics

These are the typical performance parameters measured under standard test conditions (TA=25°C, IF=5 mA unless noted).

• Luminous Intensity (Iv): A key metric for brightness. For the Blue LED, typical intensity is 110 mcd (min 38, max 310). For the Red LED, it is significantly higher at 495 mcd typical (min 110, max 880). The wide min-max ranges indicate the need for binning, discussed later.
• Viewing Angle (2θ1/2): Defined as the full angle at which intensity drops to half its axial value. Both Blue and Red versions have a typical viewing angle of 45 degrees, which is moderately wide, aided by the diffuser lens.
• Wavelength: The Blue LED has a typical dominant wavelength (λd) of 471 nm (range 465-478 nm) and a peak wavelength (λp) of 468 nm. The Red LED has a λd of 624 nm (range 617-632 nm) and a λp of 632 nm.
• Forward Voltage (VF): Blue: 3.6V typical (2.9-3.6V range). Red: 2.7V typical (1.9-2.7V range). This difference is crucial for circuit design, particularly when driving LEDs of different colors in parallel.
• Reverse Current (IR): Maximum 100 µA at VR=5V. The datasheet explicitly states the device is not designed for reverse operation; this test is for characterization only.

3. Binning System Explanation

To ensure consistency in mass production, LEDs are sorted into performance bins. This device uses two primary binning criteria.

3.1 Luminous Intensity Binning

LEDs are sorted based on their measured luminous intensity at 5 mA. Separate bin tables exist for Blue and Red LEDs, each with alphanumeric codes (e.g., BC, DE, FG for Blue; FG, HJ, KL for Red). Each bin has a defined minimum and maximum intensity value. For example, a Blue LED in the \"FG\" bin will have an intensity between 110 and 180 mcd. A tolerance of ±15% is applied to each bin limit.

3.2 Dominant Wavelength Binning

LEDs are also binned by their dominant color wavelength. The Blue LEDs are all grouped into a single bin \"1\" covering 465-478 nm. The Red LEDs are grouped into bin \"2\" covering 617-632 nm. The tolerance for wavelength bin limits is a tight ±1 nm, ensuring good color consistency within each group.

4. Performance Curve Analysis

While the PDF references typical curves, their analysis is based on standard LED behavior. The forward voltage (VF) vs. forward current (IF) curve would show an exponential relationship, with the Red LED having a lower knee voltage than the Blue LED. The luminous intensity vs. forward current curve is generally linear in the normal operating range but will saturate at higher currents. The intensity vs. ambient temperature curve would show a negative coefficient, meaning light output decreases as temperature increases. The spectral distribution curve would show a single peak around the specified λp for each color, with the Blue LED having a wider spectral half-width (Δλ of 25 nm) compared to the Red LED (Δλ of 20 nm).

5. Mechanical & Packaging Information

5.1 Outline Dimensions

The device conforms to the standard T-1 (3mm) round LED package. Key dimensions include the lens diameter, overall height, and lead spacing. The lead spacing is measured where the leads emerge from the package body. Tolerances are typically ±0.25mm unless otherwise specified. A note indicates that protruded resin under the flange is a maximum of 1.0mm.

5.2 Polarity Identification

Through-hole LEDs typically use lead length or a flat spot on the lens flange to indicate the cathode (negative lead). The longer lead is usually the anode (+). Designers must consult the physical sample or detailed drawing for the specific polarity marker.

6. Soldering & Assembly Guidelines

Proper handling is critical for reliability.

6.1 Storage Conditions

For long-term storage outside the original packaging, an environment not exceeding 30°C and 70% relative humidity is recommended. For extended periods, storage in a sealed container with desiccant or in a nitrogen ambient is advised.

6.2 Lead Forming

Bending must occur at least 3mm from the base of the LED lens to avoid stress on the internal die attach. The base of the lead frame should not be used as a fulcrum. Forming must be done at room temperature and before the soldering process.

6.3 Soldering Process

A minimum clearance of 2mm must be maintained between the solder point and the base of the lens. Dipping the lens into solder must be avoided.

• Soldering Iron: Maximum temperature 350°C, maximum time 3 seconds per lead.
• Wave Soldering: Pre-heat to a maximum of 100°C for up to 60 seconds. Solder wave temperature maximum 260°C, contact time maximum 5 seconds. The dipping position must be no lower than 2mm from the lens base.
• Important Note: Infrared (IR) reflow soldering is stated as unsuitable for this through-hole type LED product. Excessive heat or time can cause lens deformation or catastrophic failure.

6.4 Cleaning

If necessary, only alcohol-based solvents like isopropyl alcohol should be used for cleaning.

7. Packaging & Ordering Information

The standard packing flow is: 500, 200, or 100 pieces per anti-static bag. Ten of these bags are placed into an inner carton, totaling 5,000 pieces. Eight inner cartons are packed into an outer shipping carton, resulting in 40,000 pieces per outer carton. The note clarifies that in every shipping lot, only the final pack may not be a full pack.

8. Application Design Recommendations

8.1 Drive Circuit Design

LEDs are current-driven devices. To ensure uniform brightness when connecting multiple LEDs in parallel, it is strongly recommended to use a individual current-limiting resistor in series with each LED (Circuit A in the datasheet). Driving multiple LEDs in parallel directly from a voltage source with a single shared resistor (Circuit B) is discouraged, as small variations in the forward voltage (VF) characteristic between individual LEDs will cause significant differences in current and, therefore, brightness.

8.2 Electrostatic Discharge (ESD) Protection

These LEDs are susceptible to damage from electrostatic discharge. Preventive measures include: using grounded wrist straps and workstations; employing ionizers to neutralize static charge on the plastic lens; and ensuring all handling equipment is properly grounded. A focus on operator training and certification for ESD-sensitive device handling is suggested.

9. Technical Comparison & Differentiation

The key differentiating feature of this product is the use of a colored LED chip (blue or red) with a white diffuser lens. This contrasts with standard LEDs that use a clear or colored lens matching the chip color. The white diffuser provides a more uniform, softer, and potentially wider viewing light pattern, which can be preferable for front-panel indicators where a \"hot spot\" of intense color is undesirable. The electrical parameters are standard for through-hole indicator LEDs of this size.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED at 20mA continuously?
A: Yes, 20mA is the rated continuous DC forward current. However, for longest lifetime and lower junction temperature, driving at a lower current like 10mA or 5mA is often sufficient for indication purposes.

Q: Why is the forward voltage different for Blue and Red?
A: This is due to fundamental semiconductor physics. Blue LEDs are typically made from Indium Gallium Nitride (InGaN) which has a higher bandgap energy, resulting in a higher forward voltage. Red LEDs are commonly made from Aluminum Gallium Arsenide (AlGaAs) or similar materials with a lower bandgap and thus lower forward voltage.

Q: What resistor value should I use for a 5V supply?
A: Using Ohm's Law: R = (V_supply - VF_LED) / I_LED. For a Blue LED (VF=3.6V) at 5mA: R = (5 - 3.6) / 0.005 = 280 Ohms. For a Red LED (VF=2.7V) at 5mA: R = (5 - 2.7) / 0.005 = 460 Ohms. Always use the nearest standard resistor value and consider power rating.

11. Practical Design and Usage Case

Scenario: Designing a multi-status indicator panel for a network switch. A designer might use a Blue LED to indicate \"Power On/System Active\" and a Red LED to indicate \"Network Fault\". Due to the white diffuser, both indicators would have a similar, soft aesthetic appearance from the front panel, even though the emitted light colors are different. The designer must use separate current-limiting resistors for each LED due to their different forward voltages. The 45-degree viewing angle ensures the status is visible from a wide range of angles in a rack-mounted unit. The through-hole design allows for robust mechanical attachment to the PCB, which is important for equipment that may be subject to vibration during shipping or operation.

12. Operating Principle Introduction

Light Emitting Diodes (LEDs) are semiconductor devices that emit light through electroluminescence. When a forward voltage is applied across the p-n junction, electrons and holes recombine in the active region, releasing energy in the form of photons. The color (wavelength) of the emitted light is determined by the bandgap energy of the semiconductor material used. In this device, the primary light from the chip passes through an epoxy lens that contains diffusing particles. These particles scatter the light, breaking up the direct beam and creating a more uniform, wider, and less glaring emission pattern as seen by the user.

13. Technology Trends

The through-hole LED indicator market is mature. The general trend in indicator LEDs is towards higher efficiency (more light output per mA), lower power consumption, and improved reliability. While surface-mount device (SMD) LEDs dominate new designs for their smaller size and suitability for automated assembly, through-hole LEDs remain relevant for applications requiring higher mechanical strength, easier manual prototyping, or compatibility with existing legacy designs. The use of diffuser lenses for improved visual quality, as seen in this product, is a common approach to enhance the user experience without changing the core package technology.