SMD LED 19-217/Y5C-AP1Q2/3T Datasheet - Brilliant Yellow - 2.0x1.25x0.8mm - 2.0V - 25mA - English Technical Document

1. Product Overview

The 19-217/Y5C-AP1Q2/3T is a surface-mount device (SMD) LED designed for high-density electronic assemblies. This component utilizes AlGaInP (Aluminum Gallium Indium Phosphide) semiconductor technology to produce a brilliant yellow light output. Its compact form factor enables significant reductions in printed circuit board (PCB) size and overall equipment dimensions, making it ideal for space-constrained applications.

1.1 Core Advantages

• Miniaturization: The SMD package is significantly smaller than traditional lead-frame LEDs, allowing for higher component packing density on PCBs.
• Lightweight: The reduced mass is advantageous for portable and miniature electronic devices.
• Compatibility: Designed for compatibility with standard automated pick-and-place assembly equipment, streamlining the manufacturing process.
• Environmental Compliance: The product is Pb-free, compliant with RoHS, EU REACH, and halogen-free standards (Br <900 ppm, Cl <900 ppm, Br+Cl < 1500 ppm).
• Soldering: Suitable for both infrared and vapor phase reflow soldering processes.

1.2 Target Applications

This LED is suited for a variety of indicator and backlighting functions, including:

• Dashboard and switch backlighting in automotive and industrial controls.
• Status indicators and keypad backlighting in telecommunication equipment (telephones, fax machines).
• Flat backlighting for liquid crystal displays (LCDs), switches, and symbols.
• General-purpose indicator applications in consumer and industrial electronics.

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

These ratings define the limits beyond which permanent damage to the device may occur. Operation under these conditions is not guaranteed.

• Reverse Voltage (V_R): 5 V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (I_F): 25 mA. The maximum DC current for reliable long-term operation.
• Peak Forward Current (I_FP): 60 mA (Duty Cycle 1/10 @ 1 kHz). For pulsed operation only.
• Power Dissipation (P_d): 60 mW. The maximum power the package can dissipate at Ta=25\u00b0C.
• Electrostatic Discharge (ESD): Human Body Model (HBM) 2000 V. Indicates moderate ESD sensitivity; proper handling procedures are required.
• Operating Temperature (T_opr): -40 to +85 \u00b0C. The ambient temperature range for normal operation.
• Storage Temperature (T_stg): -40 to +90 \u00b0C.
• Soldering Temperature: Reflow: 260\u00b0C peak for 10 seconds max. Hand soldering: 350\u00b0C for 3 seconds max per terminal.

2.2 Electro-Optical Characteristics

Measured at a forward current (I_F) of 20 mA and an ambient temperature (T_a) of 25\u00b0C, unless otherwise specified. These are the key performance parameters.

• Luminous Intensity (I_v): 45.0 to 112.0 mcd (millicandela). The perceived brightness of the LED. The wide range is managed through binning (see Section 3).
• Viewing Angle (2\u03b8_1/2): 120 degrees (typical). This wide viewing angle makes the LED suitable for applications requiring broad visibility.
• Peak Wavelength (\u03bb_p): 591 nm (typical). The wavelength at which the spectral power distribution is maximum.
• Dominant Wavelength (\u03bb_d): 585.5 to 594.5 nm. This wavelength correlates most closely with the perceived color (brilliant yellow).
• Spectral Bandwidth (\u0394\u03bb): 15 nm (typical). The width of the emitted spectrum at half the maximum intensity (FWHM).
• Forward Voltage (V_F): 1.70 to 2.40 V (at I_F=20mA). The voltage drop across the LED when operating. A current-limiting resistor is mandatory.
• Reverse Current (I_R): 10 \u03bcA max (at V_R=5V). A small leakage current when reverse biased. The device is not intended for reverse operation.

3. Binning System Explanation

To ensure consistency in brightness and color for production runs, LEDs are sorted into bins. The part number 19-217/Y5C-AP1Q2/3T indicates specific bin selections.

3.1 Luminous Intensity Binning

Bins are defined by minimum and maximum luminous intensity values measured at I_F=20mA. The tolerance is \u00b111%.

• P1: 45.0 \u2013 57.0 mcd
• P2: 57.0 \u2013 72.0 mcd
• Q1: 72.0 \u2013 90.0 mcd
• Q2: 90.0 \u2013 112.0 mcd (This bin is specified in the part number)

3.2 Dominant Wavelength Binning

Bins ensure color consistency. The tolerance is \u00b11 nm.

• D3: 585.5 \u2013 588.5 nm
• D4: 588.5 \u2013 591.5 nm
• D5: 591.5 \u2013 594.5 nm

4. Performance Curve Analysis

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

• I-V (Current-Voltage) Curve: Shows the exponential relationship between forward voltage and current. The knee voltage is around 1.8-2.0V for AlGaInP yellow LEDs.
• Luminous Intensity vs. Forward Current: Intensity typically increases linearly with current up to a point, after which efficiency may drop due to heating.
• Luminous Intensity vs. Ambient Temperature: Output generally decreases as temperature increases. The derating factor is crucial for high-temperature applications.
• Spectral Distribution: A bell-shaped curve centered around the peak wavelength (591 nm) with a typical FWHM of 15 nm.

5. Mechanical and Package Information

5.1 Package Dimensions

The LED is housed in a standard SMD package. Key dimensions (tolerance \u00b10.1 mm unless noted) include:

• Package footprint suitable for high-density placement.
• Clear resin body for optimal light extraction.
• Anode and cathode terminals are clearly designated for correct PCB layout.

5.2 Polarity Identification

Correct polarity is essential. The package includes a marking (such as a notch, dot, or cut corner) to identify the cathode terminal. The PCB footprint design must mirror this orientation.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile (Pb-free)

A critical process for reliable assembly:

• Pre-heating: 150\u2013200\u00b0C for 60\u2013120 seconds to minimize thermal shock.
• Time Above Liquidus (TAL): >217\u00b0C for 60\u2013150 seconds.
• Peak Temperature: 260\u00b0C maximum, held for 10 seconds maximum.
• Heating Rate: Maximum 6\u00b0C/second up to 255\u00b0C.
• Cooling Rate: Maximum 3\u00b0C/second.
• Reflow Limit: The assembly should not undergo reflow soldering more than two times.

6.2 Hand Soldering

If necessary, use a soldering iron with a tip temperature <350\u00b0C, applied for <3 seconds per terminal. Use a low-power iron (<25W) and allow a cooling interval of >2 seconds between terminals. Avoid mechanical stress on the package during soldering.

6.3 Storage and Moisture Sensitivity

The product is packaged in a moisture-resistant bag with desiccant.

• Before Use: Do not open the moisture-proof bag until ready for assembly.
• After Opening: Use within 168 hours (7 days). Store unused parts at ≤30\u00b0C and ≤60% RH.
• Rebaking: If the exposure time is exceeded or desiccant is saturated, bake at 60 \u00b1 5\u00b0C for 24 hours before use.

7. Packaging and Ordering Information

7.1 Standard Packaging

The LEDs are supplied in 8mm tape on 7-inch diameter reels, compatible with automated equipment. Each reel contains 3000 pieces.

7.2 Label Explanation

Reel labels contain critical information for traceability and correct application:

• P/N: Product Number (e.g., 19-217/Y5C-AP1Q2/3T).
• CAT: Luminous Intensity Rank (e.g., Q2).
• HUE: Chromaticity Coordinates & Dominant Wavelength Rank.
• REF: Forward Voltage Rank.
• LOT No: Manufacturing lot number for quality tracking.

8. Application Design Considerations

8.1 Current Limiting is Mandatory

LEDs are current-driven devices. A series resistor must always be used to limit the forward current to the desired value (e.g., 20 mA). The resistor value is calculated using Ohm's Law: R = (V_supply - V_F) / I_F. Without this resistor, a small increase in supply voltage can cause a large, destructive increase in current.

8.2 Thermal Management

While the power dissipation is low, maintaining the junction temperature within limits is vital for longevity and stable light output. Ensure adequate PCB copper area or thermal vias if operating at high ambient temperatures or near maximum current.

8.3 Optical Design

The 120-degree viewing angle provides wide emission. For applications requiring focused light, secondary optics (lenses, light guides) may be necessary. The water-clear resin minimizes light absorption within the package.

9. Technical Comparison and Differentiation

Compared to older through-hole LEDs or other SMD packages:

• Size Advantage: The 19-217 package offers a very small footprint, enabling more compact designs than larger SMD LEDs (e.g., 3528, 5050) or through-hole parts.
• Material Technology: The use of AlGaInP semiconductor material provides high efficiency and excellent color purity in the yellow/orange/red spectrum compared to older technologies.
• Process Compatibility: Its full compatibility with standard SMT assembly lines offers a significant manufacturing cost and reliability advantage over manual insertion of through-hole components.

10. Frequently Asked Questions (FAQ)

10.1 What resistor value should I use for a 5V supply?

Using the typical V_F of 2.0V and a target I_F of 20 mA: R = (5V - 2.0V) / 0.020A = 150 \u03a9. A standard 150 \u03a9 resistor would be appropriate. Always calculate based on the maximum V_F from the datasheet to ensure current does not exceed limits under worst-case conditions.

10.2 Can I drive this LED without a current-limiting resistor if I use a constant current source?

Yes, a constant current driver set to 20 mA is an excellent alternative to a resistor and provides more stable performance over voltage and temperature variations. The resistor is simply the most common and cost-effective method.

10.3 Why is the storage time after opening the bag limited to 7 days?

SMD packages 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 floor life is a standard precaution for moisture-sensitive devices at this sensitivity level.

10.4 What does the \"Q2/3T\" in the part number signify?

This is the bin code. \"Q2\" specifies the luminous intensity bin (90-112 mcd). The \"3T\" likely refers to a specific forward voltage bin or other internal classification. Designers should specify the full part number to ensure they receive components with the desired brightness and color characteristics.

11. Practical Design and Usage Examples

11.1 Dashboard Illumination Cluster

In an automotive dashboard, multiple 19-217 LEDs can be used to backlight gauges and warning symbols. Their small size allows them to be placed directly behind icon masks on a thin PCB. The wide viewing angle ensures the symbols are evenly lit from various driver positions. A PWM (Pulse Width Modulation) signal from the vehicle's body control module can be used to dim the LEDs for night driving.

11.2 Consumer Appliance Status Indicator

For a coffee maker or router, a single 19-217 LED can serve as a \"power on\" or \"network activity\" indicator. The design involves a simple circuit: the main board's 3.3V rail, a 68 \u03a9 current-limiting resistor (for ~20mA at typical V_F), and the LED placed near a light pipe that directs the light to the front panel. Its low power consumption and reliability make it ideal for such always-on applications.

12. Operating Principle

The 19-217 LED operates on the principle of electroluminescence in a semiconductor p-n junction. When a forward voltage exceeding the junction's built-in potential is applied, electrons from the n-type AlGaInP layer are injected across the junction into the p-type layer, and holes are injected in the opposite direction. These charge carriers recombine in the active region near the junction. In AlGaInP materials, this recombination releases energy primarily in the form of photons (light) with a wavelength corresponding to the energy bandgap of the material, which is engineered to produce brilliant yellow light (~591 nm). The water-clear epoxy resin encapsulant protects the semiconductor chip and acts as a lens to shape the light output.

13. Technology Trends

The development of SMD LEDs like the 19-217 follows broader industry trends:

• Increased Efficiency: Ongoing research in epitaxial growth and chip design continues to improve the lumens-per-watt (efficacy) of AlGaInP LEDs, reducing power consumption for the same light output.
• Miniaturization: The drive for smaller devices pushes package sizes even smaller (e.g., 0402, 0201 metric packages), although these may trade off some optical performance and power handling.
• Improved Color Consistency: Advances in wafer manufacturing and binning algorithms allow for tighter control of dominant wavelength and luminous intensity, giving designers more consistent results across production batches.
• Integration: A trend towards integrating multiple LED chips (RGB, or multiple whites) into a single package, or combining the LED with driver ICs, to create more functional and simpler-to-use light sources.