Through Hole LED Lamp LTW-42FDP9H61Y Specification - White Color, Water Clear Lens - 20mA, 3.2V - English Technical Document

1. Product Overview

This document details the specifications for a through-hole mounted LED lamp. The device is a Circuit Board Indicator (CBI) type, featuring a black plastic right-angle holder (housing) designed to mate with a specific LED lamp. The assembly is characterized by its stackable design and ease of assembly, offering versatile mounting options on printed circuit boards or panels.

1.1 Core Features

• Lead (Pb) free product compliant with RoHS directives.
• Low power consumption and high luminous efficiency.
• Versatile mounting configurations: top-view (spacer) or right-angle, in horizontal or vertical arrays.
• IC compatible with low current requirements.
• Utilizes a T-1 sized lamp emitting white light through a water-clear lens.

1.2 Target Applications

This LED lamp is suitable for a broad range of electronic equipment applications, including but not limited to:

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

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

All ratings are specified at an ambient temperature (TA) of 25°C. Exceeding these limits may cause permanent damage.

• Power Dissipation: 74 mW
• Peak Forward Current: 60 mA (Duty Cycle ≤ 1/10, Pulse Width ≤ 10μs)
• DC Forward Current: 20 mA
• Current Derating: Linear from 30°C at a rate of 0.3 mA/°C
• Operating Temperature Range: -25°C to +85°C
• Storage Temperature Range: -30°C to +100°C
• Lead Soldering Temperature: 260°C maximum for 5 seconds, measured 2.0mm (0.079\") from the body.

2.2 Electrical & Optical Characteristics

Key performance parameters are measured at TA=25°C with a forward current (IF) of 20mA, unless otherwise stated.

• Luminous Intensity (Iv): Minimum 400 mcd, Typical 1000 mcd, Maximum 1900 mcd. Measurement follows CIE eye-response curve. Guarantee includes a ±15% testing tolerance.
• Viewing Angle (2θ1/2): Typically 90 degrees. Defined as the off-axis angle where intensity is half the axial value.
• Chromaticity Coordinates (x, y): Typical values are x=0.36, y=0.39, derived from the 1931 CIE chromaticity diagram.
• Correlated Color Temperature (CCT): Typically 5000 K.
• Forward Voltage (VF): Minimum 2.8 V, Typical 3.2 V, Maximum 3.7 V.
• Reverse Current (IR): Maximum 10 μA at a Reverse Voltage (VR) of 5V. The device is not designed for reverse operation.

3. Binning System Explanation

The product is classified into bins based on luminous intensity and chromaticity to ensure consistency in application.

3.1 Luminous Intensity Binning

Intensity is categorized into three bin codes at IF=20mA. Tolerance for each bin limit is ±15%.

• Bin LM: 400 mcd (Min) to 680 mcd (Max)
• Bin NP: 680 mcd (Min) to 1150 mcd (Max)
• Bin QR: 1150 mcd (Min) to 1900 mcd (Max)

The Iv classification code is marked on each individual packing bag.

3.2 Hue (Chromaticity) Binning

Chromaticity coordinates are grouped into specific hue ranks (e.g., E3, E4, F3, F4, G3, G4). Each rank defines a quadrilateral area on the CIE 1931 chromaticity diagram with specified corner coordinates (x, y). The measurement allowance for color coordinates is ±0.01.

4. Performance Curve Analysis

The datasheet references typical electrical and optical characteristic curves. These graphical representations are essential for understanding device behavior under varying conditions, though specific curve data (e.g., IV curves, relative luminous intensity vs. ambient temperature, spectral distribution) is not detailed in the provided text. Designers should consult the full datasheet for these curves to optimize drive current, understand thermal effects on light output, and ensure color consistency.

5. Mechanical & Packaging Information

5.1 Outline Dimensions

The device consists of a black plastic holder and a T-1 white LED with a water-clear lens. All dimensions are in millimeters, with a general tolerance of ±0.25mm unless otherwise specified. A detailed dimensional drawing is referenced in the datasheet, which is critical for PCB footprint design and panel cut-out sizing.

5.2 Polarity Identification & Lead Forming

During assembly, leads must be bent at a point at least 3mm from the base of the LED lens. The base of the lead frame must not be used as a fulcrum. This operation must be performed before soldering at normal temperature to avoid damaging the internal die and wire bonds.

5.3 Packing Specification

A packing specification diagram is included in the datasheet, detailing how the components are arranged in reels, trays, or other packaging formats for automated or manual handling. This information is vital for production planning and inventory management.

6. Soldering & Assembly Guidelines

6.1 Soldering Process

Important: A minimum clearance of 2mm must be maintained from the base of the lens/holder to the soldering point. The lens/holder must not be dipped into solder.

• Soldering Iron: Maximum temperature 350°C for a maximum of 3 seconds (one time only).
• Wave Soldering:
  • Pre-heat: Maximum 120°C for up to 60 seconds.
  • Solder Wave: Maximum 260°C for up to 5 seconds.

Note: IR reflow is not a suitable process for this through-hole type LED product. Exceeding temperature or time limits may cause lens deformation or catastrophic failure. The maximum wave soldering temperature does not represent the holder's Heat Deflection Temperature (HDT) or melting point.

6.2 Storage Conditions

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

6.3 Cleaning

If cleaning is necessary, use alcohol-based solvents such as isopropyl alcohol.

7. Application Notes & Design Considerations

7.1 Drive Method

LEDs are current-operated devices. To ensure uniform brightness when connecting multiple LEDs in parallel, it is strongly recommended to use a current-limiting resistor in series with each LED (Circuit Model A). Driving LEDs in parallel without individual resistors (Circuit Model 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, luminous intensity.

7.2 Electrostatic Discharge (ESD) Protection

LEDs are susceptible to damage from electrostatic discharge or power surges. Preventive measures must be implemented:

• Operators should wear conductive wrist straps or anti-static gloves when handling LEDs.
• All workstations, tools, and equipment must be properly grounded.

7.3 Mechanical Stress During Assembly

When mounting on a PCB, use the minimum clinch force necessary to avoid imposing excessive mechanical stress on the LED package, which could lead to micro-cracks or other failures.

8. Technical Comparison & Differentiation

This through-hole LED lamp differentiates itself through its integrated right-angle black holder, which simplifies assembly and provides a consistent mounting height and appearance. The combination of a water-clear lens with a white LED die typically offers higher luminous intensity compared to diffused lenses, making it suitable for applications requiring a more focused or brighter point source. The specified binning system for both intensity and chromaticity allows for tighter color and brightness matching in applications using multiple LEDs, a key advantage over non-binned or loosely binned components.

9. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this LED at 30mA for higher brightness?

A: No. The Absolute Maximum Rating for DC forward current is 20mA. Exceeding this rating risks reducing the device's lifetime or causing immediate failure. The derating curve must be followed for temperatures above 30°C.

Q: What is the purpose of the water-clear lens?

A> A water-clear (non-diffused) lens minimizes light scattering, resulting in a more directed beam with higher axial luminous intensity (candela) compared to a diffused lens which spreads light more evenly (often measured in lumens).

Q: How do I interpret the bin codes LM, NP, QR?

A> These codes represent guaranteed ranges of luminous intensity. When ordering or designing, specifying a bin code ensures you receive LEDs with brightness within that specific range, which is crucial for achieving uniform illumination across multiple indicators.

Q: Why is a series resistor mandatory for each LED in parallel?

A> The forward voltage (Vf) of LEDs has a tolerance (Min 2.8V, Typ 3.2V, Max 3.7V). Without a series resistor to regulate current, an LED with a slightly lower Vf will draw disproportionately more current from a common voltage source, leading to overdrive and potential failure, while others remain dim.

10. Practical Application Examples

Example 1: Front Panel Status Indicators: The right-angle holder allows the LED to be mounted perpendicularly to the PCB, directing light outwards through a panel cut-out. Using binned LEDs (e.g., all from Bin NP) ensures all power, network, or HDD activity lights on a device have identical brightness.

Example 2: Backlighting for Membrane Switches: The device can be mounted behind a translucent switch cap. The white light from the water-clear LED provides a bright, crisp illumination. The low current requirement makes it suitable for battery-powered handheld equipment.

Example 3: Stacked Array for Level Indication: The stackable design of the holder enables the creation of vertical or horizontal bars (e.g., for audio VU meters or signal strength indicators). Consistent chromaticity from a single hue rank ensures a uniform color across the entire array.

11. Operating Principle

This is a semiconductor light-emitting diode. When a forward voltage exceeding its characteristic forward voltage (Vf) is applied, electrons and holes recombine within the semiconductor material (typically a compound like InGaN for white light), releasing energy in the form of photons (light). The specific materials and doping determine the wavelength (color) of the emitted light. A phosphor coating is commonly used on a blue LED die to convert a portion of the blue light to longer wavelengths, creating the perception of white light. The water-clear epoxy lens encapsulates the die, provides mechanical protection, and shapes the light output pattern.

12. Technology Trends

The through-hole LED technology represented in this datasheet is a mature and reliable solution. Industry trends continue to focus on several key areas relevant to such components: increasing luminous efficacy (more light output per watt of electrical input), improving color rendering index (CRI) for white LEDs, and enhancing long-term reliability under high temperature and humidity. There is also a continuous drive for miniaturization and a broader shift towards surface-mount device (SMD) packages for automated assembly. However, through-hole LEDs remain vital for applications requiring higher mechanical strength, easier manual prototyping, or specific optical mounting configurations, as evidenced by this component's integrated holder design.