Mini Top View LED 65-21 Series - Dimensions 2.0x1.25x0.7mm - Voltage 2.7-3.5V - Blue Color - 0.11W Power - English Technical Document

1. Product Overview

The 65-21 series represents a family of Mini Top View Surface-Mount Device (SMD) Light Emitting Diodes (LEDs). These components are designed as compact, efficient optical sources primarily for indication and backlighting purposes. The series is characterized by its white surface-mount package, which houses the LED chip and provides environmental protection.

The core advantage of this series lies in its optical design. The package incorporates features that create a wide viewing angle, measured at a typical 120 degrees (2θ1/2). This is achieved through an optimized inter-reflector design within the package, which enhances light extraction and distribution. This characteristic makes these LEDs particularly well-suited for applications involving light pipes or light guides, where efficient coupling and uniform illumination are critical.

The target market includes consumer electronics, automotive interiors, industrial controls, and general lighting applications where reliable, low-power indicator lighting is required.

2. In-Depth Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device is specified to operate reliably within the following limits, beyond which permanent damage may occur:

• Reverse Voltage (V_R): 5 V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (I_F): 30 mA. The maximum DC current for continuous operation.
• Peak Forward Current (I_FP): 100 mA. This is permissible only under pulsed conditions with a duty cycle of 1/10 at 1 kHz.
• Power Dissipation (P_d): 110 mW. The maximum power the package can dissipate at an ambient temperature of 25°C.
• Operating Temperature (T_opr): -40°C to +85°C. The ambient temperature range for normal operation.
• Storage Temperature (T_stg): -40°C to +90°C.
• Soldering Temperature: For IR reflow, peak temperature should not exceed 260°C for 10 seconds. For hand soldering, the iron tip temperature should not exceed 350°C for 3 seconds.

2.2 Electro-Optical Characteristics

Key performance parameters are measured at an ambient temperature (T_a) of 25°C and a forward current (I_F) of 20 mA, unless otherwise stated.

• Luminous Intensity (I_v): Ranges from a minimum of 180 mcd to a maximum of 360 mcd, with a typical tolerance of ±11%. This defines the perceived brightness of the LED.
• Viewing Angle (2θ1/2): 120 degrees (typical). This is the full angle at which the luminous intensity drops to half of its peak value.
• Peak Wavelength (λ_p): 468 nm (typical). The wavelength at which the spectral power distribution is maximum.
• Dominant Wavelength (λ_d): Ranges from 464 nm to 472 nm, with a tolerance of ±1 nm. This defines the perceived color (blue).
• Spectral Bandwidth (Δλ): 20 nm (typical). The width of the emitted spectrum at half its maximum power.
• Forward Voltage (V_F): Ranges from 2.7 V (min) to 3.5 V (max) at 20 mA, with a typical tolerance of ±0.05V.
• Reverse Current (I_R): Maximum of 50 μA when a reverse voltage of 5V is applied.

3. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins based on key parameters.

3.1 Luminous Intensity Binning

LEDs are categorized into three bins (S1, S2, T1) based on their measured luminous intensity at I_F=20mA:
- Bin S1: 180 mcd to 225 mcd
- Bin S2: 225 mcd to 285 mcd
- Bin T1: 285 mcd to 360 mcd

3.2 Dominant Wavelength Binning

The blue color is controlled through four wavelength groups (AA1 to AA4):
- Group AA1: 464.0 nm to 466.0 nm
- Group AA2: 466.0 nm to 468.0 nm
- Group AA3: 468.0 nm to 470.0 nm
- Group AA4: 470.0 nm to 472.0 nm

3.3 Forward Voltage Binning

Forward voltage is sorted into eight bins (B34 to B41), each covering a 0.1V range from 2.70V to 3.50V. This allows designers to select LEDs with matched V_F for current-sharing in parallel circuits.

4. Performance Curve Analysis

The datasheet provides several characteristic curves that are essential for design.

• Forward Current vs. Forward Voltage (I-V Curve): Shows the exponential relationship. The curve indicates the voltage required to achieve a specific drive current, crucial for selecting current-limiting resistors or designing driver circuits.
• Relative Luminous Intensity vs. Forward Current: Demonstrates that light output increases with current but may not be perfectly linear, especially at higher currents where efficiency can drop due to heating.
• Relative Luminous Intensity vs. Ambient Temperature: Shows the thermal derating of light output. Luminous intensity decreases as ambient temperature rises, which must be accounted for in high-temperature environments.
• Forward Voltage vs. Ambient Temperature: Indicates that V_F has a negative temperature coefficient, decreasing slightly as temperature increases.
• Radiation Pattern: A polar diagram illustrating the spatial distribution of light intensity, confirming the wide, Lambertian-like emission pattern.
• Spectral Distribution: A graph plotting relative intensity against wavelength, showing the characteristic narrow blue emission peak centered around 468 nm.

5. Mechanical and Package Information

5.1 Package Outline Dimensions

The LED has a compact SMD footprint. Key dimensions include a body length of approximately 2.0 mm, a width of 1.25 mm, and a height of 0.7 mm. The anode and cathode pads are clearly defined. All unspecified tolerances are ±0.1 mm.

5.2 Recommended Solder Pad Design

A land pattern design is provided to ensure reliable soldering and proper alignment during the reflow process. Adhering to this recommended footprint helps prevent tombstoning and ensures good thermal and electrical connection.

5.3 Polarity Identification

The package features a polarity marker, typically a notch or a dot near the cathode (negative) terminal. Correct orientation is vital for circuit functionality.

6. Soldering and Assembly Guidelines

The primary soldering method is Infrared (IR) Reflow Soldering.

• Reflow Profile: The maximum peak temperature must not exceed 260°C, and the time above 260°C should be limited to 10 seconds maximum to prevent damage to the plastic package and the internal wire bonds.
• Hand Soldering: If necessary, a soldering iron with a tip temperature not exceeding 350°C may be used, with the soldering time limited to 3 seconds per lead.
• Storage Conditions: Components are packaged in moisture-resistant bags with desiccant. If the bag has been opened for more than 72 hours in an environment exceeding 30°C/60%RH, baking may be required before reflow to prevent \"popcorn\" effect during soldering.

7. Packaging and Ordering Information

7.1 Packaging Specifications

The LEDs are supplied on tape and reel for automated assembly. The carrier tape accommodates the components, and the reel dimensions are standardized. Each reel contains 2000 pieces. The packaging includes a moisture-proof aluminum bag with a desiccant and a humidity indicator card.

7.2 Label Explanation

The reel label contains critical information:
- CAT: Luminous Intensity Bin code (e.g., S1, T1).
- HUE: Dominant Wavelength Group code (e.g., AA2, AA4).
- REF: Forward Voltage Bin code (e.g., B36, B40).
- Part Number (PN), Quantity (QTY), and Lot Number (LOT NO) are also included.

8. Application Recommendations

8.1 Typical Application Scenarios

• Optical Indicators: Status lights on consumer electronics, appliances, and industrial equipment.
• Coupling into Light Guides/Light Pipes: The wide viewing angle and package design make it ideal for transferring light from the PCB to a front panel or display via an acrylic or polycarbonate light pipe.
• Backlighting: For LCD displays, keypads, membrane switches, and symbols.
• Interior Automotive Lighting: Dashboard backlighting, switch illumination, and other low-power interior lighting functions, considering the operating temperature range extends to +85°C.

8.2 Design Considerations

• Current Limiting: Always use a series resistor or constant current driver to limit I_F to the desired value (≤30 mA DC). Calculate the resistor using R = (V_supply - V_F) / I_F.
• Thermal Management: While power dissipation is low, ensure adequate PCB copper area or thermal vias if operating at high ambient temperatures or high currents to maintain performance and longevity.
• ESD Protection: The device is rated for 1000V (HBM). Implement standard ESD handling precautions during assembly. For sensitive applications, consider adding transient voltage suppression on the lines.

9. Reliability and Quality Assurance

The product undergoes a comprehensive suite of reliability tests conducted with a 90% confidence level and a Lot Tolerance Percent Defective (LTPD) of 10%. Test items include:
- Reflow Soldering Resistance
- Temperature Cycling (-40°C to +100°C)
- Thermal Shock (-10°C to +100°C)
- High & Low Temperature Storage
- DC Operating Life (1000 hrs at 20mA)
- High Temperature/High Humidity (85°C/85% RH)
These tests validate the LED's robustness under various environmental and operational stresses.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the difference between peak wavelength and dominant wavelength?
A: Peak wavelength (λ_p) is the physical wavelength of maximum spectral emission. Dominant wavelength (λ_d) is the wavelength of a monochromatic light that would appear to have the same color as the LED to the human eye. λ_d is more relevant for color specification.

Q: Can I drive this LED at 30mA continuously?
A: Yes, 30mA is the maximum continuous forward current rating. However, for optimal longevity and to account for potential thermal rise in the application, driving it at a lower current like 20mA is common practice and provides a good balance of brightness and reliability.

Q: How do I interpret the binning codes on the label?
A: The three-letter codes (e.g., CAT:T1, HUE:AA3, REF:B38) allow you to select LEDs with tightly controlled characteristics. For consistent appearance in a product, specify and use LEDs from the same or adjacent bins for luminous intensity and dominant wavelength.

11. Practical Design Case Study

Scenario: Designing a status indicator for a consumer router using a light pipe.
1. Selection: Choose an LED from the 65-21 series for its wide viewing angle, which couples efficiently into the light pipe.
2. Circuit Design: The router's logic supply is 3.3V. Targeting I_F = 15 mA for adequate brightness and lower power. Using a typical V_F of 3.0V (from bin B36), calculate the series resistor: R = (3.3V - 3.0V) / 0.015A = 20 Ω. Use a standard 20 Ω, 1/10W resistor.
3. Layout: Place the LED on the PCB according to the recommended pad layout. Position it precisely under the entrance of the light pipe. Ensure no tall components cast a shadow.
4. Thermal: Power dissipation is minimal (P = V_F * I_F ≈ 45 mW), so no special heatsinking is required in this indoor application.

12. Technical Principle Introduction

This LED is based on an Indium Gallium Nitride (InGaN) semiconductor chip. When a forward voltage exceeding the diode's junction potential is applied, electrons and holes recombine in the active region of the chip, releasing energy in the form of photons. The specific composition of the InGaN alloy determines the bandgap energy, which in turn defines the wavelength of the emitted light—in this case, in the blue spectrum (~468 nm). The package's epoxy resin lens is water-clear to maximize light transmission and is shaped to control the beam angle.

13. Industry Trends and Context

The 65-21 series fits into the ongoing trend of miniaturization and efficiency in optoelectronics. SMD LEDs continue to replace through-hole versions due to their suitability for automated assembly, smaller footprint, and lower profile. The wide viewing angle feature addresses the growing need for components that work effectively with light guides in modern, sleek product designs where the light source is often hidden. Furthermore, the availability of precise binning allows for greater color and brightness consistency in mass production, which is increasingly important for consumer electronics and automotive applications where aesthetic uniformity is demanded.