SMD LED 19-217 Brilliant Yellow Datasheet - Package Dimensions - Forward Voltage 1.7-2.2V - Luminous Intensity 18-36mcd - English Technical Document

1. Product Overview

The 19-217 is a surface-mount device (SMD) LED designed for compact and high-density electronic assemblies. It utilizes AlGaInP chip technology to produce a brilliant yellow light output. Its primary advantages include a significantly reduced footprint compared to leaded LEDs, enabling smaller PCB designs and higher packing density. The lightweight construction makes it suitable for miniature and portable applications. This component is compliant with RoHS, REACH, and halogen-free standards, making it suitable for modern electronic manufacturing.

1.1 Core Features and Target Market

The LED is supplied on 8mm tape on a 7-inch diameter reel, compatible with standard automated pick-and-place equipment. It is designed for use with infrared and vapor phase reflow soldering processes. As a mono-color type, it is optimized for applications requiring a consistent, brilliant yellow indicator or backlight. Its primary target markets include consumer electronics, telecommunications equipment (for indicators and keypad backlighting), automotive dashboard and switch illumination, and general backlighting for LCDs and symbols.

2. Technical Parameter Deep-Dive

2.1 Absolute Maximum Ratings

These ratings define the limits beyond which permanent damage to the device may occur. The maximum reverse voltage (VR) is 5V. The continuous forward current (IF) should not exceed 25mA, with a peak forward current (IFP) of 60mA allowed under pulsed conditions (1/10 duty cycle at 1kHz). The maximum power dissipation (Pd) is 60mW. The device can withstand an electrostatic discharge (ESD) of 2000V (Human Body Model). The operating temperature range (Topr) is from -40°C to +85°C, and the storage temperature (Tstg) ranges from -40°C to +90°C. Soldering temperature limits are specified for both reflow (260°C max for 10 seconds) and hand soldering (350°C max for 3 seconds).

2.2 Electro-Optical Characteristics

Measured at a standard test current of 5mA and an ambient temperature of 25°C, the key performance parameters are defined. The luminous intensity (Iv) has a typical range from 18.0 mcd to 36.0 mcd. The device features a wide viewing angle (2θ1/2) of 120 degrees. The peak wavelength (λp) is typically 591 nm, with the dominant wavelength (λd) specified between 585.5 nm and 594.5 nm. The spectral bandwidth (Δλ) is approximately 15 nm. The forward voltage (VF) ranges from 1.7V to 2.2V. The reverse current (IR) is guaranteed to be less than 10 μA at the maximum reverse voltage of 5V. Important tolerances are noted: luminous intensity (±11%), dominant wavelength (±1 nm), and forward voltage (±0.05V).

3. Binning System Explanation

To ensure consistency in production, LEDs are sorted into bins based on key parameters. This allows designers to select components that meet specific application requirements for brightness and color.

3.1 Luminous Intensity Binning

LEDs are categorized into three bins (M1, M2, N1) based on their measured luminous intensity at 5mA. Bin M1 covers 18.0-22.5 mcd, M2 covers 22.5-28.5 mcd, and N1 covers 28.5-36.0 mcd.

3.2 Dominant Wavelength Binning

Color consistency is managed through dominant wavelength bins D3 (585.5-588.5 nm), D4 (588.5-591.5 nm), and D5 (591.5-594.5 nm).

3.3 Forward Voltage Binning

Forward voltage is binned in 0.1V steps from 1.7V to 2.2V, with bins labeled 19 through 23 (e.g., Bin 19: 1.7-1.8V, Bin 20: 1.8-1.9V, etc.). This helps in designing consistent current drive circuits.

4. Performance Curve Analysis

The datasheet references typical electro-optical characteristic curves. While not displayed in the provided text, these curves typically illustrate the relationship between forward current and luminous intensity, the effect of ambient temperature on light output, and the spectral power distribution. Analyzing these curves is crucial for understanding performance under non-standard conditions, such as driving the LED at currents other than 5mA or operating in elevated temperature environments. Designers should consult the full graphical datasheet for this detailed analysis.

5. Mechanical and Package Information

5.1 Package Dimensions

The 19-217 LED has a compact SMD footprint. The detailed dimensioned drawing specifies the length, width, height, pad sizes, and their relative positions. All unspecified tolerances are ±0.1 mm. Precise adherence to these dimensions is vital for PCB land pattern design to ensure proper soldering and alignment.

5.2 Polarity Identification

The component marking and/or the shape of the package typically indicates the cathode (negative) terminal. Correct polarity must be observed during assembly to prevent device failure.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

A lead-free reflow profile is recommended. Key phases include: pre-heating between 150-200°C for 60-120 seconds; a time above liquidus (217°C) of 60-150 seconds; a peak temperature not exceeding 260°C, held for a maximum of 10 seconds; and controlled cooling rates. The maximum heating rate should be 6°C/sec, and the time above 255°C should not exceed 30 seconds. Reflow should not be performed more than twice.

6.2 Hand Soldering

If hand soldering is necessary, the iron tip temperature must be below 350°C, and contact time per terminal should be limited to 3 seconds or less. Use a soldering iron with a capacity under 25W. Allow a cooling interval of at least 2 seconds between soldering each terminal to prevent thermal damage.

6.3 Storage and Moisture Sensitivity

The LEDs are packaged in moisture-resistant bags with desiccant. The bag must not be opened until the components are ready for use. After opening, unused LEDs should be stored at ≤30°C and ≤60% relative humidity and used within 168 hours (7 days). If the storage time is exceeded or the desiccant indicates moisture absorption, a baking treatment at 60±5°C for 24 hours is required before use.

7. Packaging and Ordering Information

7.1 Reel and Tape Specifications

The components are supplied on 8mm carrier tape wound on a 7-inch diameter reel. Each reel contains 3000 pieces. Detailed reel and carrier tape dimensions are provided, with standard tolerances of ±0.1mm unless otherwise specified.

7.2 Label Explanation

The reel label contains critical information: Customer's Product Number (CPN), Product Number (P/N), Packing Quantity (QTY), Luminous Intensity Rank (CAT), Chromaticity/Dominant Wavelength Rank (HUE), Forward Voltage Rank (REF), and Lot Number (LOT No).

8. Application Suggestions

8.1 Typical Application Scenarios

• Automotive: Backlighting for dashboard instruments, switches, and control panels.
• Telecommunications: Status indicators and keypad backlighting in phones and fax machines.
• Consumer Electronics: Flat backlighting for small LCD displays, switch illumination, and symbolic indicators.
• General Purpose: Any application requiring a small, reliable, brilliant yellow indicator light.

8.2 Design Considerations

Current Limiting: An external current-limiting resistor is mandatory. The LED's forward voltage has a negative temperature coefficient, meaning a slight increase in voltage can cause a large, potentially destructive increase in current. The resistor value should be calculated based on the supply voltage, the LED's forward voltage (use the maximum value from the bin or datasheet for safety), and the desired forward current (not to exceed 25mA continuous).

Thermal Management: While the power dissipation is low, ensuring adequate PCB copper area around the thermal pads (if any) and avoiding placement near other heat-generating components will help maintain LED performance and longevity, especially at high ambient temperatures.

ESD Protection: Although rated for 2000V HBM, standard ESD handling precautions should be followed during assembly and handling.

9. Technical Comparison and Differentiation

The 19-217 LED's primary differentiation lies in its combination of AlGaInP technology for high-efficiency yellow light, a compact SMD package for space savings, and compliance with modern environmental regulations (RoHS, Halogen-Free). Compared to older through-hole yellow LEDs, it offers superior placement speed, reliability, and design flexibility. Its wide 120-degree viewing angle makes it suitable for applications where light needs to be visible from a broad range of perspectives.

10. Frequently Asked Questions (FAQs)

Q: Can I drive this LED without a series resistor?
A: No. The datasheet explicitly warns that a slight voltage shift can cause a large current change, leading to burnout. A current-limiting resistor is essential for reliable operation.

Q: What is the difference between peak wavelength and dominant wavelength?
A: Peak wavelength (λp) is the single wavelength where the spectral output is highest. Dominant wavelength (λd) is the single wavelength of monochromatic light that would produce the same perceived color. λd is more relevant for color specification in lighting applications.

Q: How do I interpret the bin codes on the label?
A: The CAT code corresponds to the luminous intensity bin (M1, M2, N1). The HUE code corresponds to the dominant wavelength bin (D3, D4, D5). The REF code corresponds to the forward voltage bin (19-23). Matching these codes allows for consistent performance across multiple units in a production run.

Q: Why is there a strict 7-day usage window after opening the moisture-proof bag?
A> SMD components can absorb moisture from the atmosphere. During reflow soldering, this trapped moisture can rapidly vaporize, causing internal delamination or \"popcorning,\" which damages the device. The 7-day window assumes standard factory floor conditions.

11. Practical Design and Usage Case

Case: Designing a Status Indicator Panel
A designer is creating a compact control panel with multiple yellow status indicators. They select the 19-217 LED for its small size and brilliant color. Using the maximum forward voltage (2.2V) from the datasheet and a target current of 20mA (within the 25mA limit) with a 5V supply, they calculate the series resistor: R = (Vsupply - Vf) / If = (5V - 2.2V) / 0.020A = 140 Ohms. A standard 150 Ohm resistor is chosen. The PCB land pattern is designed exactly per the package dimension drawing. During assembly, the reels are kept sealed until loaded into the pick-and-place machine. The specified reflow profile is used. After assembly, the panel provides bright, uniform yellow indicators with a wide viewing angle for operators.

12. Operating Principle Introduction

The 19-217 LED is a solid-state light source based on a semiconductor chip made from Aluminum Gallium Indium Phosphide (AlGaInP). When a forward voltage is applied across the P-N junction, electrons and holes are injected into the active region where they recombine. This recombination process releases energy in the form of photons (light). The specific composition of the AlGaInP alloy determines the bandgap energy, which in turn defines the wavelength (color) of the emitted light—in this case, brilliant yellow (~591 nm). The epoxy resin encapsulant serves to protect the chip, shape the light output beam (achieving the 120-degree viewing angle), and provide mechanical stability.

13. Technology Trends and Developments

The trend in SMD LEDs like the 19-217 continues towards higher efficiency (more lumens or millicandelas per watt), improved color consistency through tighter binning, and even smaller package sizes to enable further miniaturization of end products. There is also a strong focus on enhancing reliability and longevity under a wider range of environmental stresses, including higher temperature operation for automotive applications. The drive for sustainability pushes for full compliance with evolving environmental directives and the reduction or elimination of rare-earth materials where possible. The underlying AlGaInP technology remains a mature and reliable choice for producing high-quality red, orange, and yellow light.