LTL1CHKSKNN LED Lamp Datasheet - 3.1mm Diameter - 2.4V Forward Voltage - Yellow Color - 75mW Power - English Technical Document

1. Product Overview

This document details the specifications for a through-hole LED lamp. These LEDs are offered in a 3.1mm diameter package with a water-clear lens and are constructed using AlInGaP technology to produce yellow light. They are designed for versatile mounting on printed circuit boards or panels and are suitable for a wide range of status indication applications across multiple industries.

1.1 Features

• Halogen-free product (Cl<900ppm, Br<900ppm; Cl+Br<1500ppm).
• High luminous intensity output.
• Low power consumption.
• High efficiency.
• Versatile mounting on P.C. Board or panel.
• I.C. Compatible / low current requirement.
• 3.1 mm diameter package.
• AlInGaP Yellow Lamp & Water clear lens.

1.2 Applications

• Communication equipment
• Computer peripherals
• Consumer electronics
• Home appliances
• Industrial equipment

2. Technical Parameters Deep Analysis

2.1 Absolute Maximum Ratings

The device must not be operated beyond these limits, as permanent damage may occur. All ratings are specified at an ambient temperature (TA) of 25°C.

• Power Dissipation: 75 mW
• Peak Forward Current: 60 mA (1/10 Duty Cycle, 0.1ms Pulse Width)
• DC Forward Current: 30 mA
• Current Derating: Linear from 50°C at 0.4 mA/°C
• Operating Temperature Range: -40°C to +100°C
• Storage Temperature Range: -55°C to +100°C
• Lead Soldering Temperature: 260°C for 5 seconds maximum, measured 2.0mm from the LED body.

2.2 Electrical & Optical Characteristics

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

• Luminous Intensity (Iv): Minimum 140 mcd, Typical 320 mcd, Maximum 1150 mcd. The classification code is marked on each packing bag. Guaranteed values include a ±15% testing tolerance.
• Viewing Angle (2θ1/2): 45 degrees. This is the full angle at which luminous intensity is half the axial (on-axis) intensity.
• Peak Emission Wavelength (λP): 591 nm (typical).
• Dominant Wavelength (λd): Ranges from 582 nm to 596 nm, depending on the specific bin (see Section 4).
• Spectral Line Half-Width (Δλ): 15 nm (typical).
• Forward Voltage (VF): 2.4V typical at IF=20mA, with a minimum of 2.05V.
• Reverse Current (IR): 100 µA maximum at a reverse voltage (VR) of 5V. Important: The device is not designed for reverse operation; this test condition is for characterization only.

3. Binning System Specification

The LEDs are sorted into bins based on luminous intensity and dominant wavelength to ensure consistency in applications.

3.1 Luminous Intensity Binning

Unit: mcd @ IF=20mA. Tolerance for each bin limit is ±15%.

• Bin GH: 140 – 240 mcd
• Bin JK: 240 – 400 mcd
• Bin LM: 400 – 680 mcd
• Bin NP: 680 – 1150 mcd

3.2 Dominant Wavelength Binning

Unit: nm @ IF=20mA. Tolerance for each bin limit is ±1nm.

• Bin H14: 582.0 – 584.0 nm
• Bin H15: 584.0 – 586.0 nm
• Bin H16: 586.0 – 588.0 nm
• Bin H17: 588.0 – 590.0 nm
• Bin H18: 590.0 – 592.0 nm
• Bin H19: 592.0 – 594.0 nm
• Bin H20: 594.0 – 596.0 nm

4. Mechanical & Packaging Information

4.1 Outline Dimensions

The LED features a standard 3.1mm diameter round package with two axial leads.

• All dimensions are in millimeters (inches provided in tolerance).
• Tolerance is ±0.25mm (.010\") unless otherwise specified.
• Protruded resin under the flange is 1.0 mm (.04\") maximum.
• Lead spacing is measured where the leads emerge from the package body.

4.2 Packaging Specifications

• LEDs are packed in quantities of 1000, 500, 200, or 100 pieces per anti-static bag.
• 10 packing bags are placed into one inner carton, totaling 10,000 pieces.
• 8 inner cartons are packed into one outer shipping carton, totaling 80,000 pieces.
• In every shipping lot, only the last pack may be a non-full pack.

5. Soldering & Assembly Guidelines

5.1 Storage

The recommended storage ambient should not exceed 30°C temperature or 70% relative humidity. LEDs removed from their original packaging should be used within three months. For longer storage outside the original packaging, store 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.

5.3 Lead Forming

Bend leads at a point at least 3mm from the base of the LED lens. Do not use the base of the lead frame as a fulcrum. Lead forming must be done at normal temperature and before soldering. During PCB assembly, use the minimum clinch force possible to avoid mechanical stress.

5.4 Soldering Process

Maintain a minimum clearance of 2mm from the base of the lens to the soldering point. Avoid dipping the lens into solder. Do not apply external stress to the leads while the LED is hot.

Recommended Conditions:

• Soldering Iron: 350°C max, 3 seconds max (one time only).
• Wave Soldering:
  • Pre-heat: 100°C max for 60 seconds max.
  • Solder Wave: 260°C max for 5 seconds max.
  • Dipping Position: No lower than 2mm from the base of the epoxy bulb.

Warning: Excessive temperature or time can deform the lens or cause catastrophic failure. IR reflow is not suitable for this through-hole LED product.

6. Application & Design Recommendations

6.1 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 individual LED (Circuit A). Using a single resistor for multiple parallel LEDs (Circuit B) is not recommended, as differences in the forward voltage (I-V) characteristics of individual LEDs will cause uneven current distribution and thus uneven brightness.

6.2 ESD (Electrostatic Discharge) Protection

This LED is susceptible to damage from static electricity or power surges.

• Use a conductive wrist strap or anti-static gloves when handling.
• Ensure all equipment, workstations, and storage racks are properly grounded.
• Use an ion blower to neutralize static charge that may build up on the plastic lens.
• Ensure personnel working in static-safe areas are properly trained and ESD-certified.

6.3 Application Suitability

This LED lamp is suitable for indoor and outdoor signage, as well as ordinary electronic equipment. Its halogen-free construction, wide operating temperature range, and robust packaging make it a reliable choice for demanding environments.

7. Performance Curves & Typical Characteristics

The datasheet references typical characteristic curves which would normally illustrate the relationship between key parameters. Designers should consider the following based on the provided data:

• Luminous Intensity vs. Current: Intensity increases with forward current but is subject to the absolute maximum ratings for power and current.
• Forward Voltage vs. Current: The VF is specified at 20mA. Design the driving circuit to account for the typical 2.4V drop and potential variation.
• Temperature Dependence: The DC forward current must be derated linearly above 50°C ambient at 0.4 mA/°C. Luminous intensity typically decreases with increasing junction temperature.
• Spectral Characteristics: The dominant wavelength defines the perceived yellow color. The 15nm spectral half-width indicates a relatively pure color emission typical of AlInGaP technology.

8. Technical Comparison & Design Considerations

8.1 Key Differentiators

• Material Technology: Uses AlInGaP (Aluminum Indium Gallium Phosphide) for yellow emission, which generally offers higher efficiency and better temperature stability compared to older technologies like GaAsP.
• Halogen-Free: Compliant with environmental regulations restricting halogenated materials (Cl, Br).
• Wide Binning: The extensive luminous intensity and wavelength binning allows designers to select the precise performance grade needed for cost-optimization or performance matching.

8.2 Design Checklist

1. Verify the required luminous intensity and select the appropriate bin (GH, JK, LM, NP).
2. Determine if a specific yellow hue (dominant wavelength bin H14-H20) is critical for the application.
3. Calculate the series resistor value based on the supply voltage, typical VF (2.4V), and desired operating current (≤ 30mA DC).
4. In the PCB layout, ensure the recommended 2mm clearance from the LED body to the solder pad is maintained.
5. Plan for ESD protection during handling and assembly.
6. Consider thermal management if operating near the maximum temperature or current limits.

9. Frequently Asked Questions (FAQs)

9.1 Can I drive this LED without a current-limiting resistor?

No. An LED is a diode with a non-linear I-V curve. Connecting it directly to a voltage source will typically cause excessive current to flow, exceeding the Absolute Maximum Rating and destroying the device. A series resistor is mandatory for constant-voltage drive.

9.2 What is the difference between Peak Wavelength and Dominant Wavelength?

Peak Wavelength (λP) is the wavelength at which the spectral power distribution is highest. Dominant Wavelength (λd) is derived from the CIE chromaticity diagram and represents the single wavelength that best matches the perceived color of the light. For monochromatic LEDs like this yellow one, they are often close, but λd is the more relevant parameter for color specification.

9.3 Why is there a 15% tolerance on the luminous intensity bin limits?

This tolerance accounts for measurement uncertainty in the production test equipment. It means a device from the \"JK\" bin (240-400 mcd) could test as low as 204 mcd or as high as 460 mcd at the customer's facility and still be within the specified binning system. Designers must account for this potential spread in brightness.

9.4 Can I use IR reflow soldering for this LED?

No. The datasheet explicitly states that IR reflow is not a suitable process for this through-hole type LED lamp. The recommended methods are hand soldering with an iron or wave soldering, adhering strictly to the time and temperature limits provided.

10. Practical Application Example

10.1 Status Indicator Panel

Scenario: Designing a control panel with 10 yellow status indicators, powered from a 5V DC rail. Uniform brightness is important.

Design Steps:

1. LED Selection: Choose LEDs from a single luminous intensity bin (e.g., LM bin for medium-high brightness) to minimize variation.
2. Current Setting: Select a safe operating current. Using the typical current of 20mA is standard and well within the 30mA maximum.
3. Resistor Calculation: For each LED:
   • Supply Voltage (Vs) = 5V
   • LED Forward Voltage (Vf) = 2.4V (typical)
   • Desired Current (If) = 0.020 A
   • Resistor Value R = (Vs - Vf) / If = (5 - 2.4) / 0.02 = 130 Ohms.
   • Resistor Power P = (Vs - Vf) * If = (2.6) * 0.02 = 0.052W. A standard 1/8W (0.125W) resistor is sufficient.
4. Layout: Place each LED and its 130-ohm resistor in series on the PCB. Ensure the LED polarity is correct (anode typically connected to the positive supply via the resistor). Maintain the 2mm solder pad clearance.
5. Assembly: Follow the lead forming, soldering, and ESD guidelines during production.

This approach ensures reliable, consistent, and long-lasting operation of all indicator LEDs.