T-1 Through Hole LED Lamp LTLR1DESTBKJ Specification - Blue & Yellow - 3.2V/2.1V - 70mW/75mW - English Technical Document

1. Product Overview

This document details the specifications for a through-hole LED lamp identified by part number LTLR1DESTBKJ. The device is offered in a standard T-1 type package, which is a common form factor for status indication and panel lighting applications. The product is designed to provide reliable performance with low power consumption and is compliant with environmental regulations.

1.1 Core Advantages

• Low Power Consumption & High Efficiency: Optimized for energy-sensitive applications.
• Environmental Compliance: The product is lead-free, RoHS compliant, and halogen-free (Cl<900 ppm, Br<900 ppm, Cl+Br<1500 ppm).
• Package Variety: Available in a T-1 through-hole package suitable for manual or automated insertion.
• Chip Technology: Utilizes InGaN technology for the blue emitter and AlInGaP technology for the yellow emitter, combined with a white diffused lens for a uniform appearance.

1.2 Target Applications

This LED is suitable for a wide range of applications requiring clear visual status indication, including but not limited to:

• Communication equipment
• Computer peripherals and motherboards
• Consumer electronics
• Home appliances

2. In-Depth Technical Parameter Analysis

The following sections provide a detailed breakdown of the device's operational limits and performance characteristics.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. Operation at or near these limits is not recommended for extended periods.

2.2 Electrical & Optical Characteristics

These are the typical performance parameters measured under standard test conditions (TA=25°C, IF=10mA).

Key Notes:

• Luminous intensity is measured per the CIE eye-response curve.
• The viewing angle (2θ1/2) is 40 degrees, indicating a moderately wide beam.
• The device is not designed for reverse voltage operation; the IR test is for characterization only.

3. Binning System Specification

To ensure color and brightness consistency in production, LEDs are sorted into bins. The bin codes for this product are defined below.

3.1 Luminous Intensity Binning

Tolerance of each bin limit is ±30%.

3.2 Dominant Wavelength Binning

Tolerance of each bin limit is ±1nm.

4. Mechanical & Packaging Information

4.1 Outline Dimensions

The LED uses a standard T-1 (3mm) radial leaded package. Key dimensional notes include:

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

4.2 Packing Specification

The product is packed to facilitate handling and automated assembly.

• Basic Unit: 500, 200, or 100 pieces per packing bag.
• Inner Carton: 10 packing bags per inner carton (total 5,000 pieces).
• Outer Carton: 8 inner cartons per outer carton (total 40,000 pieces).
• In every shipping lot, only the last pack may be a non-full pack.

5. Soldering & Assembly Guidelines

Proper handling is critical to maintain LED performance and reliability.

5.1 Storage

Store LEDs in an environment not exceeding 30°C and 70% relative humidity. If removed from the original packaging, use within three months. For extended storage, use a sealed container with desiccant or a nitrogen ambient.

5.2 Cleaning

Use alcohol-based solvents like isopropyl alcohol if cleaning is necessary.

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.
• Perform lead forming at normal temperature and before soldering.
• Use minimum clinch force during PCB assembly to avoid mechanical stress.

5.4 Soldering Process

Maintain a minimum clearance of 2mm from the base of the lens to the solder point. Avoid dipping the lens into solder.

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

6. Application Design Considerations

6.1 Drive Circuit Design

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 A). Using a single resistor for multiple parallel LEDs (Circuit B) is not recommended due to variations in individual LED forward voltage (VF), which will cause uneven brightness.

6.2 ESD (Electrostatic Discharge) Protection

Static electricity can damage the LED. Implement the following precautions:

• Use a conductive wrist strap or anti-static gloves when handling.
• Ensure all equipment, worktables, and storage racks are properly grounded.
• Use an ionizer to neutralize static charge in the work area.

7. Performance Curves & Typical Characteristics

The datasheet references typical performance curves which graphically represent the relationship between key parameters. While the specific graphs are not reproduced in text, they typically include:

• Relative Luminous Intensity vs. Forward Current: Shows how light output increases with current, up to the maximum rating.
• Forward Voltage vs. Forward Current: Illustrates the diode's I-V characteristic curve.
• Relative Luminous Intensity vs. Ambient Temperature: Demonstrates the decrease in light output as junction temperature rises.
• Spectral Distribution: Depicts the relative power emitted across wavelengths, showing the peak emission wavelength (λP).

Designers should consult these curves to understand device behavior under non-standard conditions (e.g., different drive currents or temperatures).

8. Technical Comparison & Differentiation

This T-1 LED offers a balance of performance and cost for general-purpose indication. Key differentiators in its class include:

• Dual-Chip Technology: The use of InGaN for blue and AlInGaP for yellow provides efficient, saturated colors compared to older technologies like phosphor-converted white or less efficient chip materials.
• Halogen-Free Construction: Exceeds basic RoHS compliance, making it suitable for applications with stricter environmental requirements.
• Clear Binning Structure: Well-defined intensity and wavelength bins allow for tighter color and brightness matching in applications requiring multiple LEDs.

9. Frequently Asked Questions (FAQs)

9.1 What is the recommended operating current?

While the absolute maximum DC current is 20mA (Blue) and 30mA (Yellow), the standard test condition and typical performance data are given at 10mA. For most applications aiming for a balance of brightness and longevity, operating at or near 10mA is advisable. Always refer to the derating curves if operating at higher ambient temperatures.

9.2 Can I drive multiple LEDs with one resistor?

It is not recommended. Due to natural variations in the forward voltage (VF) of individual LEDs, connecting them in parallel with a single series resistor will result in uneven current distribution and thus uneven brightness. Always use a separate current-limiting resistor for each LED when connecting in parallel.

9.3 Is this LED suitable for outdoor use?

The datasheet states it is good for indoor and outdoor signs. However, the operating temperature range is -30°C to +85°C. For harsh outdoor environments with direct weather exposure, additional design considerations are necessary, such as conformal coating on the PCB, UV-stable lenses if applicable, and ensuring the operating temperature within the enclosure stays within limits.

9.4 What does the ±30% tolerance on luminous intensity mean?

This means the actual measured luminous intensity of any given LED can vary by up to 30% from the nominal bin value. For example, an LED from the "HJ" bin for Blue (180-310 mcd) could measure as low as 126 mcd (70% of 180) or as high as 403 mcd (130% of 310) and still be within specification. This is why binning is important for consistency.

10. Practical Application Example

Scenario: Designing a status indicator panel for a network router using a blue LED (LTLR1DESTBKJ, Blue, Bin HJ).

1. Circuit Design: The system power is 5V. Target forward current (IF) is 10mA for adequate brightness and efficiency. Using the typical forward voltage (VF) of 3.2V for Blue:
   Required series resistor R = (Vsupply - VF) / IF = (5V - 3.2V) / 0.01A = 180 Ω.
   The nearest standard value of 180 Ω or 220 Ω can be used. The resistor power rating: P = I²R = (0.01)² * 180 = 0.018W, so a standard 1/8W or 1/10W resistor is sufficient.
2. PCB Layout: Place the LED on the board, ensuring the hole spacing matches the LED's lead spacing. Keep the solder pads at least 2mm away from the LED body outline to respect the soldering clearance requirement.
3. Assembly: Insert the LED, form the leads (if necessary) at >3mm from the body, and solder using a controlled iron at 350°C for less than 3 seconds per lead.

This example ensures reliable operation within all specified parameters.