LTW-4CLDQAH246 LED Lamp Datasheet - White - 20mA - 3.0V - Through-Hole CBI Holder - English Technical Document

1. Product Overview

This document details the specifications for a white InGaN LED lamp integrated into a black plastic right-angle holder, commonly referred to as a CBI (Circuit Board Indicator). This component is designed for through-hole mounting on printed circuit boards (PCBs). The primary function is to serve as a status or indicator light in various electronic devices.

1.1 Core Advantages

• Ease of Assembly: The design is optimized for straightforward and efficient circuit board assembly processes.
• Enhanced Contrast: The black housing material provides a high contrast ratio, improving the visibility of the illuminated LED.
• Low Halogen Content: The materials comply with low halogen requirements, which is important for environmental and safety regulations.
• Compatibility: The LED is compatible with integrated circuits (ICs) and has low current requirements, making it suitable for modern digital electronics.
• Package Form: It features a rectangular package with a water-clear lens for the white LED.

1.2 Target Applications

This LED lamp is intended for use in a broad range of electronic equipment, including but not limited to:

• Computer systems and peripherals
• Communication devices
• Consumer electronics
• Industrial equipment and controls

2. Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The following ratings must not be exceeded under any conditions, as doing so may cause permanent damage to the device. All values are specified at an ambient temperature (TA) of 25°C.

• Power Dissipation (Pd): 72 mW
• Peak Forward Current (IFP): 60 mA (Duty Cycle ≤ 1/10, Pulse Width ≤ 10ms)
• Continuous Forward Current (IF): 20 mA
• Derating Factor: Linear derating from 30°C at 0.3 mA/°C
• Operating Temperature Range: -40°C to +85°C
• Storage Temperature Range: -40°C to +100°C
• Lead Soldering Temperature: 265 ±5°C for a maximum of 5 seconds, measured 2.0mm from the body.

2.2 Electrical and Optical Characteristics

These are the typical performance parameters measured at TA=25°C and a forward current (IF) of 20 mA, unless otherwise noted.

• Luminous Intensity (Iv): 680 mcd (Min), 1500 mcd (Typ), 2500 mcd (Max). Measurement includes a ±15% testing tolerance.
• Viewing Angle (2θ1/2): 100 degrees (Typical). This is the full angle at which luminous intensity drops to half its axial value.
• Chromaticity Coordinates (x, y): x=0.29, y=0.28 (Typical). Derived from the CIE 1931 chromaticity diagram.
• Forward Voltage (VF): 2.5 V (Min), 3.0 V (Typ), 3.5 V (Max) at IF=20mA.
• Reverse Current (IR): 100 μA (Max) at a Reverse Voltage (VR) of 5V. Important: The device is not designed for operation in reverse bias; this test condition is for characterization only.

3. Binning System Explanation

The LEDs are sorted (binned) based on their measured optical performance to ensure consistency within an application.

3.1 Luminous Intensity Binning

LEDs are classified into bins according to their minimum and maximum luminous intensity at 20mA. The tolerance for each bin limit is ±15%.

• Bin N: 680 mcd to 880 mcd
• Bin P: 880 mcd to 1150 mcd
• Bin Q: 1150 mcd to 1500 mcd
• Bin R: 1500 mcd to 1900 mcd
• Bin S: 1900 mcd to 2500 mcd

The specific bin code is marked on each packing bag.

3.2 Hue (Chromaticity) Binning

LEDs are also binned based on their color coordinates (x, y) on the CIE 1931 diagram to control color variation. The document defines several hue ranks (A1, A2, B1, B2, C1, C2, D1, D2), each specifying a quadrilateral area on the chromaticity chart. The measurement allowance for color coordinates is ±0.01. This binning ensures that LEDs from the same hue rank will appear visually similar in color.

4. Mechanical and Packaging Information

4.1 Outline and Dimensions

The product consists of a white LED lamp assembled into a black plastic right-angle holder. Key mechanical notes include:

• All dimensions are provided in millimeters, with tolerances of ±0.25mm unless otherwise specified.
• The holder (housing) material is black plastic.
• The LED itself is white with a water-clear lens.

Note: The specific dimensional drawing is referenced in the source document but not reproduced in text here. Designers must refer to the original datasheet for exact mechanical drawings.

4.2 Packaging Specifications

The LEDs are packaged in the following hierarchy:

1. Packing Bag: Contains 1000, 500, 200, or 100 pieces.
2. Inner Carton: Contains 15 packing bags, totaling 15,000 pieces.
3. Outer Carton (Shipping Carton): Contains 8 inner cartons, totaling 120,000 pieces.

A note specifies that in every shipping lot, only the final pack may not be a full pack.

5. Assembly and Handling Guidelines

5.1 Storage Conditions

For optimal shelf life, LEDs should be stored in an environment not exceeding 30°C temperature or 70% relative humidity. If removed from their original moisture-barrier packaging, it is recommended to use them within three months. For longer-term storage outside the original bag, they should be kept in a sealed container with desiccant or in a nitrogen ambient.

5.2 Cleaning

If cleaning is necessary, use alcohol-based solvents such as isopropyl alcohol. Avoid using other harsh chemicals.

5.3 Lead Forming and PCB Assembly

• Lead forming (bending) must be performed before soldering and at room temperature.
• The bend should be made at a point at least 3mm away from the base of the LED lens. Do not use the base of the lead frame as a fulcrum.
• During PCB insertion, apply the minimum clinch force necessary to avoid imposing excessive mechanical stress on the component.

5.4 Soldering Instructions

Critical Rule: Maintain a minimum distance of 2mm between the base of the lens and the solder point. Do not immerse the lens in solder.

Hand Soldering (Iron):

• Temperature: Maximum 350°C
• Time: Maximum 3 seconds per lead (one time only)

Wave Soldering:

• Pre-heat Temperature: Maximum 120°C
• Pre-heat Time: Maximum 100 seconds
• Solder Wave Temperature: 265 ±5°C
• Soldering Time: Maximum 5 seconds

Important Notes:

• Excessive temperature or time can deform the lens or cause catastrophic failure.
• IR reflow soldering is not suitable for this through-hole type LED product.
• The maximum wave soldering temperature (265°C) refers to the solder itself, not the heat deflection temperature (HDT) of the plastic holder.

6. Application and Circuit Design

6.1 Drive Method

LEDs are current-operated devices. To ensure uniform brightness when driving multiple LEDs, it is strongly recommended to use a current-limiting resistor in series with each LED (Circuit A). Driving multiple LEDs in parallel without individual resistors (Circuit B) is not recommended, as slight variations in the forward voltage (Vf) characteristic of each LED will cause significant differences in current share and, consequently, brightness.

Recommended Circuit (A): [Power Supply] -- [Resistor] -- [LED] -- [Ground] (Repeat for each LED).

6.2 Electrostatic Discharge (ESD) Protection

LEDs are sensitive to electrostatic discharge (ESD) and voltage surges, which can cause immediate or latent damage. Standard ESD prevention practices must be followed during handling and assembly:

• Use a grounded wrist strap and work on a grounded anti-static mat.
• Store and transport components in ESD-protective packaging.
• Ensure all equipment and tools are properly grounded.

6.3 Application Suitability

This LED lamp is suitable for both indoor and outdoor signage applications, as well as general electronic equipment. The right-angle holder design makes it ideal for applications where the PCB is mounted parallel to the viewing surface, such as front panels of instruments or control boards.

7. Performance Curves and Graphical Data

The source document references a section for "Typical Electrical/Optical Characteristics Curves." These curves are essential for detailed design analysis and typically include:

• Relative Luminous Intensity vs. Forward Current: Shows how light output changes with drive current.
• Forward Voltage vs. Forward Current: The I-V characteristic curve of the LED.
• Relative Luminous Intensity vs. Ambient Temperature: Illustrates the derating of light output as temperature increases.
• Viewing Angle Pattern: A polar plot showing the spatial distribution of light.

Designer Note: For precise design calculations, especially concerning thermal management and driver design, consulting the graphical data in the original datasheet is crucial.

8. Technical Comparison and Design Considerations

8.1 Differentiation from Similar Products

The key differentiator of this product is the integrated CBI (Circuit Board Indicator) holder. Compared to a standalone LED, this assembly offers:

• Simplified Assembly: The holder provides mechanical stability and consistent positioning height on the PCB.
• Improved Aesthetics and Contrast: The black housing offers a professional look and enhances the perceived brightness of the LED.
• Right-Angle Form Factor: Enables side-emitting applications without requiring additional brackets or hardware.

8.2 Design Considerations Based on Parameters

• Current Limiting: Always use a series resistor. Calculate the resistor value using R = (Vsupply - Vf_LED) / If, where Vf_LED should be taken as the typical or maximum value from the datasheet to ensure the current does not exceed 20mA under worst-case conditions.
• Thermal Management: While the power dissipation is low (72mW max), the derating curve indicates performance decreases above 30°C. In high ambient temperature environments or enclosures, ensure adequate ventilation or consider reducing the drive current.
• Optical Design: The 100-degree viewing angle provides a wide beam. For applications requiring a more focused spot, an external lens or a different LED package would be necessary.

9. Frequently Asked Questions (FAQ)

9.1 Can I drive this LED without a resistor if my power supply is exactly 3.0V?

No. This is not recommended. The forward voltage (Vf) has a range (2.5V to 3.5V). If your supply is 3.0V and you connect an LED with a Vf at the low end of the range (e.g., 2.6V), the excess voltage will cause excessive current to flow, potentially damaging the LED. The series resistor is essential for regulating current.

9.2 What is the meaning of the bin code on the bag?

The bin code (e.g., "Q" and "B2") indicates the LED's performance group. The letter (N, P, Q, R, S) specifies its luminous intensity range. The alphanumeric code (A1, B2, etc.) specifies its color (chromaticity) coordinates on the CIE chart. Using LEDs from the same bin ensures consistency in brightness and color within your product.

9.3 Is this LED suitable for automotive applications?

The datasheet specifies an operating temperature range of -40°C to +85°C, which covers many automotive under-hood and cabin requirements. However, automotive applications often require additional qualifications for vibration, humidity, and extended lifetime under specific test conditions (e.g., AEC-Q102). This standard datasheet does not claim such qualifications. For automotive use, consult the manufacturer for grade-specific data.

9.4 Can I use reflow soldering for this component?

No. The datasheet explicitly states that "IR reflow is not suitable process for through-hole type LED lamp product." This component is designed for wave soldering or hand soldering processes only.