LTST-FS63HBGED SMD LED Datasheet - Side Looking Full Color - 0.30mm Thin - Blue/Green/Red - English Technical Document

1. Product Overview

The LTST-FS63HBGED is a highly integrated, surface-mount device (SMD) LED lamp designed for modern, space-constrained electronic applications. It represents a specialized configuration within the miniature LED family, engineered specifically for automated printed circuit board (PCB) assembly processes. This device combines three distinct semiconductor light sources within a single, exceptionally thin package, enabling full-color capability in a minimal footprint.

1.1 Core Advantages and Product Positioning

This LED's primary competitive advantage lies in its ultra-thin profile of 0.30 mm, making it a side-looking component. This form factor is critical for applications where vertical space is severely limited, such as in ultra-slim mobile devices, wearable technology, and edge-lit panels. The integration of Blue (InGaN), Green (InGaN), and Red (AlInGaP) chips allows for the generation of a broad spectrum of colors through individual or combined control, eliminating the need for multiple discrete single-color LEDs. The package utilizes a white diffused lens, which helps to blend the light from the three chips and provides a more uniform appearance when viewed off-axis.

1.2 Target Market and Applications

The device is targeted at a wide array of electronic equipment manufacturers. Its key application segments include:

• Consumer Electronics: Backlighting for keypads, keyboards, and status indicators in cordless/cellular phones, notebook computers, tablets, and remote controls.
• Office Automation & Network Systems: Status and activity indicators in routers, switches, modems, printers, and external storage devices.
• Home Appliances & Industrial Equipment: User interface illumination, operational status lights, and symbolic indicators on control panels.
• Display Technology: Suitable for microdisplays and as a compact luminary source for small-scale signal and symbol illumination.

The device is fully compatible with high-volume, automated placement equipment and infrared (IR) reflow soldering processes, aligning with modern, RoHS-compliant manufacturing lines.

2. In-Depth Technical Parameter Analysis

A thorough understanding of the electrical and optical characteristics is essential for reliable circuit design and achieving desired performance.

2.1 Absolute Maximum Ratings

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

• Power Dissipation (Pd): Varies by color: Blue: 97.5 mW, Green: 100.5 mW, Red: 81.0 mW. This parameter, combined with thermal resistance (implied by derating curves), dictates the maximum sustainable forward current at elevated ambient temperatures.
• Forward Current: Continuous DC forward current is rated at 30 mA for all three colors. A higher peak forward current of 100 mA is permissible but only under pulsed conditions (1/10 duty cycle, 0.1ms pulse width) to manage junction temperature.
• Electrostatic Discharge (ESD) Threshold: Rated at 2000V (Human Body Model). This is a standard level for consumer-grade components, necessitating standard ESD handling precautions during assembly.
• Temperature Ranges: Operating: -40°C to +85°C; Storage: -40°C to +100°C. The wide operating range makes it suitable for both consumer and some industrial environments.
• Soldering Condition: Withstands IR reflow at 260°C peak temperature for 10 seconds, compatible with lead-free (Pb-free) solder processes.

2.2 Electrical & Optical Characteristics (Typical at Ta=25°C)

These are the standard test conditions and typical performance values used for design and binning.

• Luminous Intensity (Iv): Measured at specific test currents (Blue: 12mA, Green: 30mA, Red: 30mA). The typical value is 2750 mcd (millicandela), with a minimum of 1735 mcd and a maximum of 4265 mcd. The variation is addressed by the binning system.
• Viewing Angle (2θ1/2): A very wide 130 degrees (typical). This is the full angle at which luminous intensity drops to half its on-axis value, characteristic of a side-emitting LED with a diffused lens, providing broad, even illumination.
• Wavelength Parameters:
  • Peak Emission Wavelength (λP): Blue: 466 nm, Green: 516 nm, Red: 632 nm (typical).
  • Dominant Wavelength (λd): The range defines the perceived color. Blue: 467-477 nm, Green: 516-526 nm, Red: 618-628 nm.
  • Spectral Line Half-Width (Δλ): Blue: 25 nm, Green: 35 nm, Red: 20 nm (typical). This indicates the spectral purity; a smaller Δλ means a more monochromatic light.
• Forward Voltage (Vf): The voltage drop across the LED at the test current. Ranges are: Blue: 2.45-3.25V, Green: 2.55-3.35V, Red: 1.90-2.70V. This range must be considered for driver design, especially for constant-voltage supplies.
• Reverse Current (Ir): Maximum of 10 μA at a reverse voltage (Vr) of 5V. This test is for quality assurance; the device is not designed for operation in reverse bias.

3. Binning System Explanation

To ensure color and brightness consistency in production, LEDs are sorted into bins. The LTST-FS63HBGED uses two primary binning criteria.

3.1 Luminous Intensity (Iv) Rank

LEDs are sorted based on their measured luminous intensity at the standard test currents. The bins are defined as:
- Bin BB: 1735 mcd (Min) to 2340 mcd (Max).
- Bin CC: 2340 mcd (Min) to 3160 mcd (Max).
- Bin DD: 3160 mcd (Min) to 4265 mcd (Max).
A tolerance of +/-15% is applied within each bin. Designers must specify the required bin to guarantee a minimum brightness level for their application.

3.2 Hue (Color Chromaticity) Rank

This is a more complex two-dimensional binning based on the CIE 1931 (x, y) chromaticity coordinates. The datasheet provides a matrix of bins (e.g., B0, B1, B2, B3, C0, C1... D3). Each bin is defined by a quadrilateral area on the color chart. For example, Bin B0 covers coordinates within the boundaries defined by (x: 0.2685-0.2885, y: 0.2730-0.3010). A tolerance of +/- 0.01 is allowed on each (x, y) coordinate within a bin. This system ensures that all LEDs within a specific Hue bin will appear visually identical in color under standard conditions, which is critical for applications requiring uniform color appearance across multiple indicators.

4. Performance Curve Analysis

The provided characteristic curves offer deeper insight into device behavior under varying conditions.

4.1 Relative Intensity vs. Wavelength (Fig.1)

This spectral distribution curve shows the relative light output power at each wavelength. It visually confirms the peak wavelengths (λP) and spectral half-widths (Δλ) for each color chip. The curves for InGaN (Blue and Green) typically show a sharper peak compared to AlInGaP (Red), which may have a slightly broader spectrum.

4.2 Forward Current vs. Forward Voltage (Fig.2)

This IV curve is non-linear and exponential in nature, typical of a diode. The curve will show different turn-on voltages for the Red (AlInGaP, ~1.9V) versus the Blue/Green (InGaN, ~2.5-3.0V). The slope of the curve in the operating region represents the dynamic resistance of the LED. This graph is crucial for designing constant-current drivers to ensure stable operation across the forward voltage range.

4.3 Forward Current Derating Curve (Fig.3)

This is one of the most critical graphs for reliability. It shows the maximum allowable continuous forward current as a function of the ambient temperature (Ta). As Ta increases, the maximum current must be reduced to prevent the LED junction temperature from exceeding its limit, which would accelerate lumen depreciation and reduce lifespan. The curve typically shows a linear derating from a specified current at 25°C down to zero at the maximum junction temperature (implied by the max operating temperature).

4.4 Relative Luminous Intensity vs. Forward Current (Fig.4)

This curve shows that light output (luminous intensity) increases with forward current, but the relationship is not perfectly linear, especially at higher currents where efficiency may drop due to increased heat. It helps designers choose an operating current that balances brightness with efficiency and longevity.

4.5 Radiation Pattern (Fig.5 & Fig.6)

These polar diagrams illustrate the spatial distribution of light intensity. A side-looking LED with a diffused lens typically shows a wide, lambertian-like emission pattern. Fig.5 (Horizontal) and Fig.6 (Vertical) would show the intensity as a function of angle from the central axis, confirming the 130-degree viewing angle. The pattern should be symmetrical for consistent off-axis appearance.

5. Mechanical, Packaging & Assembly Information

5.1 Package Dimensions and Pin Assignment

The device conforms to an EIA standard package outline. Critical dimensions include the overall length, width, and the ultra-critical thickness of 0.30 mm. The pin assignment is clearly defined: Pin 3 is the common cathode (or anode, depending on internal construction; the datasheet specifies it as the common pin for all three colors). The anode for the Red chip is Pin 1, for Green is Pin 2, and for Blue is Pin 4. This information is vital for correct PCB layout and orientation during assembly.

5.2 Recommended PCB Pad Design & Soldering Direction

The datasheet includes a land pattern recommendation. This shows the optimal size and shape of the copper pads on the PCB to ensure a reliable solder joint while minimizing tombstoning (component standing up on one end during reflow). It also indicates the proper orientation of the LED on the tape relative to the PCB for automated pick-and-place machines.

5.3 Tape and Reel Packaging Specifications

The LEDs are supplied on 8mm wide embossed carrier tape wound onto 7-inch (178 mm) diameter reels. Key specifications include:
- Pocket Dimensions: Precise cavity size to hold the LED securely.
- Pitch: The distance between component pockets (e.g., 4mm).
- Reel Dimensions: Hub diameter, flange diameter, and overall width.
- Quantity: 4000 pieces per full reel.
- Cover Tape: Used to seal the pockets; it must have the correct peel strength for the placement machine.
- Packaging Standards: Complies with ANSI/EIA-481.
- Quality Rules: Maximum of two consecutive missing components allowed; minimum pack quantity for remnants is 500 pieces.

6. Assembly, Handling, and Application Guidelines

6.1 Soldering Process

The device is qualified for infrared (IR) reflow soldering with a lead-free profile. The critical parameter is a peak temperature of 260°C for a duration of 10 seconds, as defined in the absolute maximum ratings. Designers must ensure their reflow oven profile stays within these limits to avoid damaging the plastic package or the internal wire bonds.

6.2 Cleaning

Post-solder cleaning must be performed with care. Only specified solvents should be used. The datasheet recommends immersion in ethyl alcohol or isopropyl alcohol at normal room temperature for less than one minute. Harsher chemicals or prolonged exposure can damage the epoxy lens or package markings.

6.3 Electrostatic Discharge (ESD) Precautions

Although rated at 2000V HBM, the device is susceptible to ESD damage. Proper handling procedures are mandatory: use grounded wrist straps, anti-static mats, and ensure all equipment is properly grounded. The LED should not be handled directly with bare hands.

6.4 Storage Conditions

To preserve shelf life, the LEDs should be stored in their original moisture-barrier bag at conditions of 30°C or less and 90% relative humidity or less. The recommended use-within period is one year from the date of shipment while stored under these conditions. If the bag has been opened or the humidity indicator card shows excessive moisture exposure, baking may be required before reflow to prevent \"popcorning\" (package cracking due to rapid vapor expansion).

6.5 Application Cautions

The datasheet explicitly states the intended use for \"ordinary electronic equipment.\" For applications requiring exceptional reliability where failure could jeopardize life or health (aviation, medical, transportation safety systems), prior consultation and qualification with the manufacturer is required. This highlights the component's classification for commercial/industrial use, not necessarily for safety-critical applications without further vetting.

7. Design Considerations and Typical Application Circuits

7.1 Driving the LED

Due to the exponential IV characteristic, LEDs must be driven by a current source, not a voltage source, for stable light output. The simplest method is to use a series current-limiting resistor with a voltage supply. The resistor value (R) is calculated as R = (V_supply - Vf_LED) / If, where Vf_LED is the forward voltage of the specific color chip at the desired current (If). Since Vf has a range, the resistor should be chosen to ensure If does not exceed the maximum rating even with the minimum Vf. For precision or battery-powered applications, a dedicated constant-current LED driver IC is recommended. Each color chip must be driven independently to enable full-color mixing.

7.2 Thermal Management

Despite its small size, managing junction temperature is key to longevity. The primary path for heat dissipation is through the solder pads into the PCB copper. Therefore, using the recommended pad layout and maximizing the copper area connected to the pads (thermal relief) is important. Avoid operating at the absolute maximum current, especially in high ambient temperatures, and refer to the derating curve.

7.3 Optical Integration

The white diffused lens provides a blended light output. For applications requiring specific beam patterns, secondary optics (light guides, reflectors) may be designed around the LED. The wide viewing angle makes it suitable for edge-lighting thin light guides commonly used in button backlighting.

8. Technical Comparison and Differentiation

The LTST-FS63HBGED's main differentiators in the market are:
1. Form Factor: The 0.30mm thickness is a key enabler for ultra-thin designs, distinguishing it from standard top-emitting SMD LEDs which are typically taller.
2. Integration: Combining three primary color chips in one package saves PCB space and simplifies assembly compared to using three separate LEDs.
3. Performance: The use of InGaN for blue/green and AlInGaP for red provides high efficiency and good color saturation.
4. Manufacturability: Full compatibility with automated, high-speed SMT assembly lines makes it cost-effective for mass production.

9. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive all three colors simultaneously at their maximum DC current of 30mA each?
A: No. The total power dissipation must be considered. Simultaneous operation at 30mA each would likely exceed the package's total power dissipation capability, leading to overheating. The derating curve and individual Pd ratings must be used to determine safe simultaneous operating currents based on ambient temperature.

Q: Why are the test currents different for the Blue (12mA) versus Green/Red (30mA) chips?
A> This is related to the inherent efficiency and operating characteristics of the different semiconductor materials (InGaN vs. AlInGaP). The manufacturer has chosen test currents that represent a typical, efficient operating point for each chip to achieve the target luminous intensity while managing heat and longevity.

Q: How do I achieve white light with this RGB LED?
A: White light is created by mixing the three primary colors at specific intensity ratios. This requires independent pulse-width modulation (PWM) or analog current control of each chip. The exact ratios depend on the chromaticity bins of the specific LEDs used and the target white point (e.g., cool white, warm white).

Q: Is reverse voltage protection required?
A> While the device can withstand a 5V reverse bias test, it is not designed for operation in reverse. If there is any possibility of reverse voltage being applied in the circuit (e.g., in an inductive load or with an AC-coupled signal), an external protection diode in series or parallel (depending on configuration) should be used.