LTL-R42NM1H229 LED Indicator Specification Sheet - Through-Hole - Yellow/Green Bicolor - 20mA - 52mW - Technical Documentation

1. Product Overview

LTL-R42NM1H229 is a through-hole LED indicator specifically designed for Circuit Board Indication (CBI). It consists of a black plastic right-angle bracket (housing) and two independent LED chips. This component is designed for easy installation onto a Printed Circuit Board (PCB), providing a reliable and cost-effective solution for status indication.

1.1 Core Advantages

• Easy Assembly:Optimized design for simple and efficient installation on circuit boards.
• Enhanced contrast:The black housing material provides high contrast, improving visibility when the LED is illuminated.
• High Energy Efficiency:It features low power consumption and high luminous efficacy.
• Environmental Compliance:This is a lead-free product compliant with the RoHS (Restriction of Hazardous Substances) directive.
• Dual-color option:Integrates two different LED colors: standard yellow (approx. 589nm) and green/yellow-green (approx. 569nm).

1.2 Target Applications

This LED indicator is suitable for various electronic devices that require clear status or indicator lights. The main application areas include:

• Communication equipment
• Computers and Peripherals
• Consumer Electronics
• Industrial Control Systems

2. Detailed Technical Parameters

This section provides a detailed and objective analysis of the key electrical, optical, and thermal parameters of the LTL-R42NM1H229 LED indicator.

2.1 Absolute Maximum Ratings

These ratings define the limiting conditions beyond which permanent damage to the device may occur. Functional operation under these conditions is not guaranteed.

• Power Dissipation (P_D):Each LED 52 mW. This is the maximum power that the LED can continuously dissipate at an ambient temperature (T_A) of 25°C. Exceeding this limit risks thermal damage.
• Peak forward current (I_FP):60 mA. This current is only allowed under pulse conditions (duty cycle ≤ 1/10, pulse width ≤ 0.1ms). Not suitable for DC operation.
• DC Forward Current (I_F):20 mA. This is the maximum continuous forward current recommended for long-term reliable operation.
• Operating Temperature Range:-30°C to +85°C. The device is designed to operate within this ambient temperature range.
• Storage Temperature Range:-40°C to +100°C. The device can be safely stored within this range when not in operation.
• Pin soldering temperature:Maximum 260°C, maximum 5 seconds, measurement point 2.0mm (0.079 inches) from LED body. This defines the thermal profile tolerance during hand or wave soldering.

2.2 Electrical and Optical Characteristics

These are typical performance parameters, measured under the condition of T_A=25°C, I_F=10mA, unless otherwise specified.

• Luminous intensity (I_V):A key metric for measuring brightness.
  • Yellow LED: typical value 11 mcd, range from 3.8 mcd (min) to 30 mcd (max).
  • Green/Yellow-green LED: typical value 19 mcd, range from 8.7 mcd (min) to 50 mcd (max).
  • Note:Measurement includes a test tolerance of ±15%. Green LEDs exhibit higher typical brightness.
• Viewing angle (2θ_1/2):Both colors are 100 degrees. This wide viewing angle ensures the LED is visible from a broad range of positions relative to its axis.
• Peak Wavelength (λ_P):The wavelength at which the emitted light intensity is highest.
  • Yellow: 591 nm
  • Green: 572 nm
• Dominant Wavelength (λ_d):Represents the color of light perceived by the human eye.
  • Yellow: 589 nm (range 584-594 nm)
  • Green/Yellow-green: 569 nm (range 566-574 nm)
• Spectral line half-width (Δλ):Both colors are approximately 15 nm, indicating relatively narrow and pure emission colors.
• Forward voltage (V_F):Typical value 2.0V, maximum 2.5V at I_F=10mA. This low voltage is compatible with common low-voltage logic circuits.
• Reverse current (I_R):At V_R=5V, maximum is 100 μA.Key Note:This device is not designed to operate under reverse bias; this parameter is for test purposes only. Applying reverse voltage in a circuit will damage the LED.

3. Binning System Description

This product employs a binning system, which classifies LEDs based on their luminous intensity (I_V) and hue (dominant wavelength). This ensures consistency within the same production batch.

3.1 Luminous Intensity Binning

LEDs are sorted into different bins (A, B, C, D) based on their light output measured at 10mA. The datasheet specifies the I_VBin limits have a ±15% tolerance. This means the brightness levels of LEDs within the same bin will be very close, which is crucial for applications requiring uniform appearance of multiple indicator lights.

3.2 Hue (Wavelength) Binning

LED further classified by its dominant wavelength. Tolerance for each hue bin is ±1nm. This strict control ensures minimal color variation between individual LEDs of the same nominal color (yellow or green), which is crucial for aesthetic consistency and color-coded indicator systems.

The binning table (e.g., codes like L2, L3, H06, 3ST) associates specific luminous intensity and hue bin combinations with final product codes (A, B, C, D), allowing for precise selection based on application requirements.

4. Performance Curve Analysis

Although the PDF references typical characteristic curves, the behavior of a standard LED can be inferred:

4.1 Forward Current vs. Forward Voltage (I-V Curve)

LED ni diode, yana nuna alaƙar I-V mara layi. Ƙarfin lantarki mai gaba (V_F) yana da ƙimar zafin jiki mara kyau, ma'ana yana raguwa kaɗan yayin da zafin haɗin gwiwa ya ƙaru. V da aka ƙayyade a 10mA_Fyana kusan 2.0-2.5V, shine ma'auni mai mahimmanci don ƙirar kewaye na tuƙi mai iyakancewar ƙarfin lantarki.

4.2 Luminous Intensity vs. Forward Current

Within the recommended operating range (up to 20mA), the light output (I_V) is approximately proportional to the forward current (I_F). Driving the LED beyond this current increases brightness, but also increases power consumption and junction temperature, potentially shortening lifespan and causing color shift.

4.3 Temperature Dependence

LED performance is sensitive to temperature. Luminous intensity typically decreases as junction temperature increases. The specified operating temperature range of -30°C to +85°C defines the environmental conditions under which the published optical characteristics are valid. Operation at higher temperatures will result in reduced light output.

5. Mechanical and Packaging Information

5.1 Outline Dimensions

The device adopts a right-angle through-hole design. Key dimension specifications include:

• All dimensions are in millimeters. The default tolerance is ±0.25mm, unless otherwise specified on the dimension drawing.
• The housing material is black plastic.
• LED1 is green/yellow-green, equipped with a matching green diffuser lens.
• LED2 is yellow, equipped with a matching yellow diffuser lens.

Lura: Cikakkun zane-zanen girma an ambace su a cikin littafin ƙayyadaddun bayanai, amma ba a kwafi su a nan a cikin rubutu ba. Masu zane dole ne su koma ga ainihin zane don samun cikakkun bayanai game da sanyawa da cikakkun bayanai na kunshe.

5.2 Polarity Identification

For through-hole LEDs, the cathode is typically identified by a flat edge on the LED lens, a shorter lead, or a marking on the housing. The dimension drawing in the datasheet should clearly indicate the polarity. Correct polarity is crucial; reverse connection will prevent illumination and may damage the device if the reverse voltage exceeds 5V.

5.3 Packaging Specification

Products are supplied in packaging suitable for automatic assembly or manual handling. The packaging specifications detail the quantity of components per reel, tube, or tray, as well as the orientation of components within the packaging to facilitate pick-and-place machines or prevent damage during transportation and storage.

6. Welding and Assembly Guide

Proper handling is crucial to ensure reliability and prevent damage.

6.1 Storage Conditions

For long-term storage outside the original moisture barrier bag, it is recommended to store LEDs in an environment of ≤30°C and relative humidity ≤70%. If removed from the original packaging, use within three months. For longer storage, use a sealed container with desiccant or a nitrogen environment.

6.2 Cleaning

For cleaning, use only alcohol-based solvents such as isopropyl alcohol. Avoid using strong or unknown chemical cleaners that may damage plastic lenses or housings.

6.3 Pin Forming

If pin bending is required, it must be performedbefore solderingat room temperature. The bending point should be at least 3mm away from the LED lens base. Do not use the LED body as a fulcrum. Apply minimal force when inserting into the PCB to avoid mechanical stress on the pins or epoxy seal.

6.4 Soldering Parameters

Key Rules:Maintain a minimum distance of 2mm between the solder joint and the root of the LED lens. Do not immerse the lens in solder.

• Soldering iron:Maximum temperature 350°C. Maximum contact time per pin 3 seconds. Operate only once.
• Wave soldering:
  • Preheating: up to 120°C, maximum 100 seconds.
  • Solder wave: up to 260°C.
  • Soldering time: maximum 5 seconds.
  • Immersion position: not less than 2mm from the lens root.
• Warning:Temperatures or durations that are too high can melt plastic lenses, degrade epoxy, or cause catastrophic failure of semiconductor junctions.

7. Application Design Recommendations

7.1 Drive Circuit Design

LED ni abin da ke amfani da ƙarfin lantarki. Don tabbatar da aiki mai ƙarfi da tsawon rayuwa, dole ne a haɗa resistor mai iyakancewa a jere tare da kowane LED. Ana lissafta ƙimar resistor (R) ta amfani da dokar Ohm: R = (V_{Wutar lantarki}- V_F) / I_F, where V_Fis the LED forward voltage (use typical or maximum value for design margin), I_Fis the required forward current (≤20mA).

Circuit Model A (Recommended):Each LED has its own dedicated current-limiting resistor. This provides optimal brightness uniformity and independent current control, as it compensates for the slight differences in the I-V characteristics of each LED.

Circuit Model B (not recommended for uniformity):Multiple LEDs are connected in parallel, sharing a single resistor. Due to the natural differences in the forward voltage of each LED, this can lead to significant brightness variations among the LEDs. V_FAn LED with a slightly lower forward voltage will draw more current and appear brighter, potentially leading to uneven current distribution and uneven wear.

7.2 ESD (Electrostatic Discharge) Protection

LEDs are sensitive to electrostatic discharge. Precautions must be taken during handling and assembly:

• Operators should wear grounded wrist straps or anti-static gloves.
• Toate stațiile de lucru, uneltele și echipamentele trebuie să fie corect împământate.
• Utilizați un ventilator ionic pentru a neutraliza sarcina electrostatică care se poate acumula pe lentilele din plastic.
• Implement ESD training and certification programs for personnel.

7.3 Thermal Management

Although the power consumption is low (52mW per LED), ensuring the device operates within its specified temperature range is crucial for maintaining light output and lifespan. Avoid placing LEDs near other heat-generating components. Sufficient spacing on the PCB allows for some natural convection cooling.

8. Technical Comparison and Differentiation

LTL-R42NM1H229 offers specific advantages in its niche:

• Integrated Dual Color:Two distinct common indicator colors (yellow and green/yellow-green) are integrated within a compact housing, saving board space compared to using two separate single-color LEDs.
• Right-Angle Design:The right-angle housing directs light parallel to the PCB surface, making it ideal for front-panel or side-emitting indicator applications where the viewing direction is from the side rather than from above.
• Black housing:Provides excellent contrast when the LED is off, making the illuminated state more noticeable, especially under bright ambient light conditions.
• Standard through-hole package:Compared to surface-mount devices that require more precise assembly processes, it offers mechanical robustness and facilitates manual soldering for prototyping or small-batch production.

9. Frequently Asked Questions (Based on Technical Parameters)

Q1: Can I drive this LED with 30mA for extra brightness?
A: A'a. Matsakaicin ƙimar ƙarfin kai tsaye na DC shine 20mA. Yin aiki a 30mA ya wuce wannan ƙimar, wanda zai ƙara yawan zafin jiki, hanzarta raguwar haske, kuma yana iya haifar da gazawa da wuri. Da fatan za a ci gaba da cikin sharuɗɗan aiki da aka ba da shawarar.

Q2: An jera ƙarfin kai tsaye a matsayin 2.0V (na al'ada) zuwa 2.5V (matsakaicin). Wane ƙimar ne ya kamata in yi amfani da shi don ƙididdige resistor na iyakancewar kwarara?
A: Don ƙirar ƙarfi, tabbatar da cewa kwarara ba zai taɓa wuce matsakaicin ƙimar ba ko da a cikin yanayin ƙimar kayan aiki, yi amfani daMaximum value V_F(2.5V). This ensures that even if the V_Fis at the low end of its range, the actual current will be at or below your target value.

Q3: What is the difference between peak wavelength and dominant wavelength?
A:Peak Wavelength (λ_P)It is the physical wavelength at which the spectral power output is highest.Dominant Wavelength (λ_d)It is a calculated value based on human color perception (CIE chromaticity diagram); it is the wavelength of a pure monochromatic light that appears the same color as the LED. λ_dIt is more relevant for describing the perceived color.

Q4: Ina iya amfani da wannan LED a waje?
A: Takardar ƙayyadaddun bayanai ta nuna cewa ta dace da alamomin cikin gida da na waje. Duk da haka, don muhallin waje mai tsanani wanda ke fuskantar hasken UV kai tsaye, ɗanɗano, da sauye-sauyen yanayin zafi, ana buƙatar ƙarin la'akari da ƙira, kamar shafa PCB da kariya uku, amfani da harsashi na kariya, da tabbatar da aiki a cikin yanayin zafi mai tsanani.

10. Practical Design and Usage Cases

Scenario: Designing a dual-state indicator light for a network router.
LTL-R42NM1H229 is an ideal choice. The green LED can indicate "Power On/System Normal", while the yellow LED can indicate "Network Activity" or "Warning".

Implementation Plan:
1. Place components on the PCB near the front panel.
2. Design two independent drive circuits, each with a current-limiting resistor. Using a 5V supply for a 15mA drive current (well below the 20mA limit), calculate: R = (5V - 2.5V) / 0.015A ≈ 167Ω (use a standard 180Ω or 150Ω resistor).
3. Connect the anode of the green LED to a GPIO pin, which is set high in the "normal" state.
4. Connect the anode of the yellow LED to another GPIO pin, which toggles with data activity.
5. Ensure the PCB layout maintains a 2mm gap from the solder pad to the lens.
6. During assembly, strictly adhere to ESD, pin forming, and soldering guidelines.

Thus, using a single component package enables a concise, professional, and reliable status indication system.

11. Introduction to Working Principles

Light-emitting diode (LED) is a semiconductor device that emits light through electroluminescence. When a forward voltage is applied across the p-n junction, electrons from the n-type material recombine with holes from the p-type material in the active region. This recombination process releases energy in the form of photons (light). The specific color (wavelength) of the emitted light is determined by the energy band gap of the semiconductor material constituting the LED chip. The yellow and green in this device are achieved by using different semiconductor material compositions (e.g., AlInGaP for yellow, InGaN for green). The diffused plastic lens above the chip is used to scatter the light, creating a wide viewing angle of 100 degrees.

12. Teknoloji Trendleri

Through-hole LED indicators remain mainstream in electronics due to their simplicity and durability, especially in applications requiring high mechanical strength or where manual assembly is common. However, the overall industry trend is shifting toward surface-mount device (SMD) LEDs, which offer smaller package sizes, lower profile heights, and compatibility with high-speed automated pick-and-place assembly lines, thereby reducing manufacturing costs for high-volume products. Furthermore, advancements in LED chip technology continuously improve luminous efficacy (more light output per watt of electrical input), allowing the same brightness to be achieved with lower drive currents, thus enhancing energy efficiency and thermal performance. The principles of careful current control, thermal management, and ESD protection remain crucial across all LED package types.