SMD LED 19-117 Blue Datasheet - Size 1.6x0.8x0.6mm - Voltage 2.6-3.0V - Power 40mW - English Technical Document

1. Product Overview

The 19-117 is a compact, surface-mount blue LED designed for modern electronic applications requiring miniaturization and high reliability. This component utilizes InGaN chip technology to produce a blue emission with a typical peak wavelength of 468nm. Its primary advantages include a significantly smaller footprint compared to leaded LEDs, enabling higher packing density on PCBs, reduced equipment size, and lighter weight for portable and miniature devices. The product is fully Pb-free, includes ESD protection, and complies with RoHS directives, making it suitable for a wide range of consumer and industrial electronics.

2. In-Depth Technical Parameter Analysis

2.1 Absolute Maximum Ratings

The device is specified for operation within strict electrical and thermal limits to ensure long-term reliability. The absolute maximum ratings define the boundaries beyond which permanent damage may occur. The reverse voltage (VR) is limited to 5V, emphasizing the need for proper circuit design to avoid accidental reverse bias. The continuous forward current (IF) is rated at 10mA, while a peak forward current (IFP) of 100mA is permissible under pulsed conditions (1/10 duty cycle at 1kHz), useful for multiplexing or brief high-brightness signaling. The maximum power dissipation (Pd) is 40mW, which is a critical parameter for thermal management, especially in densely packed boards. The device can withstand an electrostatic discharge (ESD) of 2000V per the Human Body Model (HBM), offering good handling robustness. The operating temperature range (Topr) is from -40°C to +85°C, and storage (Tstg) from -40°C to +90°C, indicating suitability for harsh environments. Soldering temperature profiles are also specified, with reflow soldering peaking at 260°C for 10 seconds maximum.

2.2 Electro-Optical Characteristics

Key performance metrics are defined at a standard test condition of 25°C ambient temperature and a forward current of 2mA. The luminous intensity (Iv) has a typical range from 5.80 mcd to 11.5 mcd, categorized into specific bins (J2, K1, K2). The viewing angle (2θ1/2) is a wide 120 degrees, providing a broad, diffuse light pattern ideal for backlighting and status indicators. The spectral characteristics include a peak wavelength (λp) of 468nm and a dominant wavelength (λd) range of 470nm to 475nm. The spectral bandwidth (Δλ) is approximately 25nm. The forward voltage (VF) ranges from 2.60V to 3.00V at 2mA, with specific voltage bins (28, 29, 30, 31) defined for tighter control in production. Tolerances are noted: ±11% for luminous intensity, ±1nm for dominant wavelength, and ±0.05V for forward voltage.

3. Binning System Explanation

The product employs a comprehensive binning system to ensure consistent performance in volume production. This system categorizes LEDs based on three key parameters:

• Luminous Intensity (CAT): Bins J2 (5.80-7.20 mcd), K1 (7.20-9.00 mcd), and K2 (9.00-11.5 mcd). This allows designers to select the appropriate brightness level for their application.
• Dominant Wavelength (HUE): A single bin 'Y' covering 470.0nm to 475.0nm, ensuring a consistent blue color output.
• Forward Voltage (REF): Bins 28 (2.60-2.70V), 29 (2.70-2.80V), 30 (2.80-2.90V), and 31 (2.90-3.00V). This is crucial for designing stable current-drive circuits and predicting power consumption accurately.

This binning information is reflected on the product label, enabling precise traceability and selection for automated assembly and quality control.

4. Performance Curve Analysis

While specific graphs are not detailed in the provided text, typical electro-optical characteristic curves for such LEDs would include:

• Forward Current vs. Forward Voltage (I-V Curve): Shows the exponential relationship, critical for determining the operating point and series resistor value.
• Luminous Intensity vs. Forward Current: Demonstrates how light output increases with current, up to the maximum rated limits.
• Luminous Intensity vs. Ambient Temperature: Illustrates the decrease in light output as junction temperature rises, a key consideration for thermal design.
• Spectral Distribution: A plot of relative intensity versus wavelength, showing the peak at ~468nm and the 25nm bandwidth.

These curves are essential for engineers to model the LED's behavior under different operating conditions and to optimize driver circuit design for efficiency and longevity.

5. Mechanical and Package Information

The 19-117 features a compact surface-mount package. The package dimensions are typically defined in a drawing with a tolerance of ±0.1mm unless otherwise specified. Key mechanical features include the overall length, width, and height, as well as the solder pad land pattern design. The polarity is indicated by a marking on the component body, such as a cathode indicator (often a green dot, notch, or similar marking). The package is designed to be compatible with standard 8mm wide carrier tape on 7-inch diameter reels, facilitating automated pick-and-place assembly processes.

6. Soldering and Assembly Guidelines

6.1 Storage and Handling

The LEDs are moisture-sensitive. Before opening, they must be stored at ≤30°C and ≤90% RH. After opening, the "floor life" is 1 year under ≤30°C and ≤60% RH. Unused parts should be resealed in moisture-proof packaging with desiccant. If the specified storage conditions or time are exceeded, a baking treatment at 60±5°C for 24 hours is required to remove absorbed moisture and prevent "popcorning" during reflow soldering.

6.2 Soldering Process

The device is compatible with infrared and vapor phase reflow processes. A specific Pb-free reflow profile is recommended: pre-heating at 150-200°C for 60-120 seconds, a time above liquidus (217°C) of 60-150 seconds, a peak temperature of 260°C maximum held for no more than 10 seconds, and controlled ramp-up/cool-down rates (max 6°C/sec and 3°C/sec respectively). Reflow should not be performed more than twice. During hand soldering, the iron tip temperature must be below 350°C, applied for no more than 3 seconds per terminal, using a low-power iron (<25W). Stress on the LED body during heating must be avoided, and board warpage after soldering is prohibited.

6.3 Circuit Protection

A current-limiting resistor is mandatory in series with the LED. The forward voltage has a negative temperature coefficient, meaning a slight increase in voltage (or decrease in Vf due to temperature rise) can cause a large, potentially destructive increase in current if not properly limited by an external resistor.

7. Packaging and Ordering Information

The standard packaging consists of 3000 pieces per reel. The carrier tape dimensions are specified to ensure compatibility with automated equipment. The product is shipped in a moisture-resistant aluminum bag containing desiccant and a humidity indicator card. The reel label contains critical information for identification and traceability, including the product number (P/N), quantity (QTY), and the specific bin codes for luminous intensity (CAT), dominant wavelength (HUE), and forward voltage (REF).

8. Application Recommendations

The 19-117 LED is well-suited for a variety of low-power indicator and backlighting applications. Its small size and wide viewing angle make it ideal for:

• Backlighting: Illumination for dashboard instruments, membrane switches, keypads, and LCD displays in consumer electronics.
• Status Indicators: Power, connectivity, or function status lights in telecommunications equipment (phones, fax machines), computer peripherals, and home appliances.
• General Purpose Signaling: Any application requiring a compact, reliable, blue visual indicator.

Design Considerations: Always use a series current-limiting resistor. Consider the effects of temperature on luminous intensity and forward voltage. Ensure the PCB layout provides adequate heat dissipation, especially if operating near maximum ratings. Adhere strictly to the recommended soldering profile and storage conditions to prevent damage.

9. Technical Comparison and Differentiation

Compared to older through-hole LEDs, the 19-117 offers significant advantages in size, weight, and suitability for automated assembly. Within the SMD blue LED category, its key differentiators are its specific combination of a 120-degree viewing angle, defined binning structure for consistent color and brightness, integrated ESD protection, and a robust moisture sensitivity level (MSL) with clear handling guidelines. The specified 2000V ESD rating provides better handling robustness than many basic LEDs.

10. Frequently Asked Questions (FAQ)

Q: What resistor value should I use with this LED?
A: The value depends on your supply voltage (Vs) and desired forward current (If, max 10mA continuous). Use Ohm's Law: R = (Vs - Vf) / If. Use the maximum Vf from the datasheet (3.00V) for a conservative design that ensures current never exceeds the limit.

Q: Can I use this LED outdoors?
A: The operating temperature range (-40°C to +85°C) allows for use in many outdoor environments. However, the package is not specifically rated for waterproofing or UV resistance. For direct exposure to weather, additional conformal coating or an enclosure is necessary.

Q: Why is the storage condition so important?
A: SMD packages can absorb moisture from the air. During the high heat of reflow soldering, this moisture can vaporize rapidly, causing internal delamination or cracking ("popcorning"), which destroys the LED. The storage and baking procedures prevent this.

Q: What does the bin code on the label mean?
A: It tells you the specific performance group for that reel of LEDs. For example, a code of K2-Y-30 indicates Luminous Intensity bin K2 (9.00-11.5 mcd), Dominant Wavelength bin Y (470-475nm), and Forward Voltage bin 30 (2.80-2.90V). This ensures consistency in your production run.

11. Practical Application Example

Scenario: Designing a low-power status indicator for a USB device.
The device operates from a 5V USB bus. The goal is to indicate "power on" with a blue LED. A forward current of 5mA is chosen for adequate brightness and low power consumption.
Calculation: Using the maximum Vf of 3.00V for safety: R = (5V - 3.00V) / 0.005A = 400 Ohms. The nearest standard value is 390 Ohms. The actual current would be: I = (5V - ~2.8V_typical) / 390Ω ≈ 5.64mA, which is safe and within spec. The LED would be placed in series with this 390Ω resistor between the 5V rail and ground (observing correct polarity). The PCB footprint would match the recommended land pattern from the package drawing.

12. Technical Principle Introduction

This LED is based on a semiconductor heterostructure using Indium Gallium Nitride (InGaN) as the active layer. When a forward voltage is applied across the p-n junction, electrons and holes are injected into the active region. Their recombination releases energy in the form of photons (light). The specific composition of the InGaN alloy determines the bandgap energy, which directly correlates to the wavelength of the emitted light—in this case, blue (~468nm). The epoxy resin lens encapsulates the chip, providing mechanical protection, shaping the light output beam (120-degree angle), and often containing phosphors if a different color (like white) were to be produced.

13. Industry Trends and Context

The 19-117 represents a mature product in the SMD LED market. Current industry trends focus on several areas beyond basic indicators: increased luminous efficacy (more light per watt), higher maximum drive currents for brighter outputs in smaller packages, improved color rendering and consistency, and integration of control electronics (like constant-current drivers) within the LED package itself. There is also a strong drive towards even higher reliability for automotive and specialized industrial applications. While this component is optimized for general-purpose use, newer generations push the boundaries in terms of power density, thermal performance, and smart features. The principles of proper circuit design, thermal management, and careful handling outlined in this datasheet remain universally applicable across all LED technologies.