SMD LED 95-21SYGC/S530-E3/TR9 Datasheet - 2.0x1.25x0.8mm - 2.0V - 40mW - Brilliant Yellow Green - English Technical Document

1. Product Overview

The 95-21SYGC/S530-E3/TR9 is a surface-mount device (SMD) LED designed for modern electronic applications requiring compact size, high reliability, and efficient performance. This component belongs to the family of miniature LEDs that have revolutionized indicator and backlighting solutions.

1.1 Core Advantages and Product Positioning

The primary advantage of this LED is its significantly reduced footprint compared to traditional leaded components. This miniaturization enables several key benefits for designers and manufacturers. Firstly, it allows for smaller printed circuit board (PCB) designs, which is critical in today's trend towards portable and miniaturized electronics. The higher packing density achievable with SMD components means more LEDs or other components can be placed in a given area, enhancing functionality without increasing size.

Secondly, the light weight of the SMD package makes it ideal for applications where mass is a concern, such as in handheld devices, wearables, and aerospace equipment. The use of automation-compatible tape and reel packaging (12mm tape on a 7-inch diameter reel) ensures high-speed, accurate placement using standard pick-and-place machines, reducing assembly time and cost while improving consistency. The product is positioned as a general-purpose indicator and backlight source for a wide range of consumer, office, and communication equipment.

1.2 Compliance and Environmental Specifications

This LED is manufactured with environmental and regulatory compliance as a priority. It is a Pb-free (lead-free) product, aligning with global restrictions on hazardous substances. The product itself remains within the compliant version of the RoHS (Restriction of Hazardous Substances) directive. It also complies with the EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulation. Furthermore, it is classified as Halogen Free, with strict limits on bromine (Br < 900 ppm), chlorine (Cl < 900 ppm), and their combined total (Br+Cl < 1500 ppm). These specifications make it suitable for markets with stringent environmental regulations.

2. In-Depth Technical Parameter Analysis

A thorough understanding of the electrical and optical parameters is essential for proper circuit design and ensuring long-term reliability.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. They are not intended for normal operation.

• Reverse Voltage (VR): 5V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (IF): 25mA. The DC current that can be applied continuously.
• Peak Forward Current (IFP): 60mA. This is the maximum allowable pulsed current, specified at a duty cycle of 1/10 and a frequency of 1kHz. It is crucial for multiplexing applications.
• Power Dissipation (Pd): 60mW. The maximum power the package can dissipate, calculated as Forward Voltage (VF) * Forward Current (IF).
• Operating & Storage Temperature: The device can operate from -40°C to +85°C and be stored from -40°C to +100°C.
• Electrostatic Discharge (ESD): 2000V (Human Body Model). Proper ESD handling procedures must be followed.
• Soldering Temperature: For reflow soldering, a peak temperature of 260°C for up to 10 seconds is specified. For hand soldering, the iron tip temperature should not exceed 350°C for 3 seconds per terminal.

2.2 Electro-Optical Characteristics (Ta=25°C)

These are the typical performance parameters under standard test conditions (20mA forward current, 25°C ambient).

• Luminous Intensity (Iv): 400mcd (Min), 630mcd (Typ). This is a measure of the perceived brightness of the light source. A ±11% tolerance is specified.
• Viewing Angle (2θ1/2): 25 degrees (Typical). This defines the angular spread at which the luminous intensity drops to half of its peak value. A 25° angle indicates a relatively focused beam, suitable for directed indicator lights.
• Peak Wavelength (λp): 575nm. The wavelength at which the spectral emission is strongest.
• Dominant Wavelength (λd): 573nm. This is the single wavelength perceived by the human eye, defining the color (brilliant yellow-green). A tolerance of ±1nm is specified.
• Spectrum Radiation Bandwidth (Δλ): 20nm. The spectral width at half the maximum intensity, indicating color purity.
• Forward Voltage (VF): 2.0V (Typ), 2.4V (Max) at 20mA. This is critical for designing the current-limiting resistor. The tolerance is ±0.1V.
• Reverse Current (IR): 10μA (Max) at VR=5V.

2.3 Device Selection and Material Composition

The LED chip is constructed from AlGaInP (Aluminum Gallium Indium Phosphide) semiconductor material. This material system is known for producing high-efficiency light in the yellow, orange, and red regions of the spectrum. The emitted color is brilliant yellow-green, and the resin encapsulating the chip is water clear, which maximizes light output and preserves the chip's color characteristics.

3. Performance Curve Analysis

The datasheet references typical electro-optical characteristic curves. While the specific graphs are not reproduced in text, their general implications are analyzed below based on standard LED behavior and the provided parameters.

3.1 Forward Current vs. Forward Voltage (I-V Curve)

For an AlGaInP LED like this one, the I-V curve exhibits a typical diode characteristic with a turn-on voltage slightly below the typical 2.0V. The curve will show an exponential increase in current once this knee voltage is exceeded. Designers must use a series resistor to set the operating current precisely at 20mA, as a small increase in voltage beyond the nominal VF can lead to a large, potentially destructive, increase in current.

3.2 Luminous Intensity vs. Forward Current (L-I Curve)

The light output (luminous intensity) is generally proportional to the forward current in the normal operating range (up to the rated 25mA). However, efficiency may drop at very high currents due to thermal effects. Operating at the typical 20mA ensures optimal performance and longevity.

3.3 Temperature Dependence

LED performance is temperature-sensitive. Typically, the forward voltage (VF) decreases with increasing junction temperature (a negative temperature coefficient). Conversely, the luminous intensity and dominant wavelength can shift. The specified operating temperature range of -40°C to +85°C indicates the device is designed to function across a wide environmental range, but designers should account for potential brightness and color shifts in extreme conditions.

4. Mechanical and Packaging Information

4.1 Package Outline Dimensions

The LED conforms to an industry-standard SMD package footprint. Key dimensions (with a general tolerance of ±0.1mm unless otherwise noted) define its size and solder pad layout. The package is designed for reliable surface mounting and good solder joint formation.

4.2 Polarity Identification

Proper polarity is essential for operation. The datasheet includes a diagram showing the cathode and anode terminals. Typically, the cathode may be marked by a notch, a green marking, or a different pad shape on the tape. Designers must consult the package diagram to correctly orient the component on the PCB footprint.

5. Soldering and Assembly Guidelines

Adherence to these guidelines is critical for assembly yield and long-term reliability.

5.1 Current Limiting Requirement

This is the most critical design rule: An external current-limiting resistor must always be used in series with the LED. The LED is a current-driven device. A slight increase in supply voltage above the LED's forward voltage will cause a large, uncontrolled increase in current, leading to rapid overheating and failure (burn-out). The resistor value is calculated using Ohm's Law: R = (V_supply - VF_LED) / I_desired.

5.2 Storage and Moisture Sensitivity

The LEDs are packaged in a moisture-resistant barrier bag with desiccant to prevent absorption of atmospheric moisture.

• Before Opening: Store at ≤30°C and ≤90% Relative Humidity (RH).
• After Opening: The "floor life" is 72 hours under conditions of ≤30°C and ≤60% RH. If not used within this time, unused parts must be resealed in a moisture-proof package with fresh desiccant.
• Baking: If the desiccant indicator shows saturation or the floor life is exceeded, the components must be baked at 60±5°C for 24 hours before use to drive out moisture and prevent "popcorning" during reflow soldering.

5.3 Reflow Soldering Profile (Pb-free)

A specific temperature profile is required for Pb-free solder alloys:

• Pre-heating: Ramp from ambient to 150-200°C over 60-120 seconds (max ramp rate 3°C/sec).
• Soak/Reflow: Time above liquidus (217°C): 60-150 seconds. Peak temperature must not exceed 260°C, and time above 255°C must not exceed 30 seconds. The component should be at peak temperature for a maximum of 10 seconds.
• Cooling: Maximum cool-down rate of 6°C/sec.
• Important: Reflow soldering should not be performed more than two times on the same board/component.

5.4 Hand Soldering and Rework

If hand soldering is necessary, extreme care is required. Use a soldering iron with a tip temperature ≤350°C and a power rating ≤25W. Contact time per terminal must be ≤3 seconds. Allow a cooling interval of at least 2 seconds between soldering each terminal. Avoid applying mechanical stress to the component during heating. Rework is strongly discouraged. If absolutely unavoidable, use a specialized double-head soldering iron to simultaneously heat both terminals and lift the component evenly to avoid damaging the solder pads or the LED itself.

6. Packaging and Ordering Information

6.1 Standard Packaging

The LEDs are supplied on embossed carrier tape sealed within a moisture-proof bag. The tape width is 12mm, wound on a standard 7-inch (178mm) diameter reel. Each reel contains 1000 pieces. Detailed dimensions for the carrier tape pockets and the reel are provided to ensure compatibility with automated assembly equipment.

6.2 Label Explanation

The packaging labels include several codes for traceability and binning:

• P/N: Product Number (95-21SYGC/S530-E3/TR9).
• LOT No: Manufacturing Lot Number for traceability.
• QTY: Packing Quantity (e.g., 1000).
• CAT: Luminous Intensity Rank (Binning for brightness).
• HUE: Dominant Wavelength Rank (Binning for color).
• REF: Forward Voltage Rank (Binning for VF).

7. Application Suggestions and Design Considerations

7.1 Typical Application Scenarios

Based on its specifications, this LED is well-suited for:

• Status Indicators: Power-on, standby, mode, or battery charge indicators in consumer electronics.
• Backlighting: For LCD panels in small devices, membrane switches, keypads, and instrument symbols.
• Office Equipment: Indicators and backlights in printers, scanners, copiers, and routers.
• Portable/Battery-Powered Devices: Ideal due to its low voltage (2.0V) and potential for efficient drive, extending battery life in phones, remote controls, and medical devices.
• Audio/Video Equipment: Display and function indicators on amplifiers, receivers, and set-top boxes.
• Automotive Interior: Backlighting for dashboard switches and controls (for non-critical illumination, noting the operating temperature range).
• Telecommunications: Indicator lights on telephones, fax machines, and network hardware.

7.2 Design Considerations

• Current Drive: Always use a constant current source or, more commonly, a voltage source with a series resistor. PWM (Pulse Width Modulation) can be used for dimming.
• Thermal Management: While the power is low (40mW at 20mA), ensure the PCB has adequate thermal relief, especially if multiple LEDs are clustered or if the ambient temperature is high.
• Optical Design: The 25° viewing angle provides a directed beam. For wider illumination, a diffuser lens or reflector may be needed in the housing.
• ESD Protection: Incorporate ESD protection diodes on sensitive input lines if the LED is user-accessible.

8. Technical Comparison and Differentiation

Compared to older through-hole LED technologies, this SMD LED offers superior size, weight, and assembly advantages. Within the SMD yellow-green LED segment, its key differentiators are its specific combination of a relatively high luminous intensity (630mcd) at a low forward current (20mA), a standard 2.0V forward voltage compatible with many logic-level voltages, and its compliance with modern environmental standards (RoHS, REACH, Halogen-Free). The AlGaInP chip technology provides good efficiency and color stability for the yellow-green spectrum.

9. Frequently Asked Questions (Based on Technical Parameters)

9.1 What resistor value should I use with a 5V supply?

Using the typical VF of 2.0V and desired IF of 20mA: R = (5V - 2.0V) / 0.020A = 150 Ohms. The nearest standard value is 150Ω. The power dissipated in the resistor is (3V * 0.02A) = 0.06W, so a standard 1/8W (0.125W) or 1/4W resistor is sufficient.

9.2 Can I drive this LED directly from a 3.3V microcontroller pin?

Possibly, but caution is needed. The typical VF is 2.0V, and a microcontroller GPIO pin can often source 20mA. However, you must verify the microcontroller's absolute maximum per-pin current and total port current. It is generally safer and more reliable to use the GPIO pin to control a transistor (e.g., a small NPN or a MOSFET) which then drives the LED with current from the main power rail.

9.3 Why is the storage temperature higher than the operating temperature?

The storage temperature (up to 100°C) refers to the non-operating, ambient temperature the component can withstand without degradation when no electrical power or current-induced heat is present. The operating temperature (up to 85°C) includes the additional heat generated by the LED's own power dissipation during use. The junction temperature during operation will be higher than the ambient, so the allowable ambient is lower to keep the junction within safe limits.

10. Practical Design and Usage Case

Scenario: Designing a multi-LED status panel for a portable data logger.

The device has a 3.7V Li-ion battery and needs 5 yellow-green LEDs to indicate recording, memory full, battery low, Bluetooth connection, and GPS lock. Using the 95-21SYGC LED, the designer would:

1. Calculate the series resistor for each LED: R = (3.7V - 2.0V) / 0.020A = 85 Ohms. Use a standard 82Ω or 100Ω resistor, adjusting for desired brightness vs. battery life.
2. Place the LEDs on the PCB with correct polarity according to the footprint diagram.
3. Drive each LED via a GPIO pin of the system's microcontroller through the calculated resistor.
4. In the firmware, implement logic to turn LEDs on/off or blink them as needed.
5. Ensure the PCB layout provides some spacing between LEDs to prevent thermal coupling and includes a ground plane for stability.
6. Specify that the assembly house follows the provided reflow soldering profile.

This approach yields a compact, reliable, and low-power indicator system suitable for the portable application.

11. Operating Principle Introduction

Light Emitting Diodes (LEDs) are semiconductor devices that emit light through a process called electroluminescence. When a forward voltage is applied across the p-n junction of the semiconductor material (in this case, AlGaInP), electrons from the n-type region and holes from the p-type region are injected into the junction region. These charge carriers recombine, releasing energy in the form of photons (light). The specific wavelength (color) of the emitted light is determined by the bandgap energy of the semiconductor material. AlGaInP has a bandgap that corresponds to light in the yellow, orange, and red parts of the visible spectrum. The "water clear" epoxy resin encapsulant protects the chip and acts as a lens, shaping the light output beam.

12. Technology Trends and Context

The component described represents a mature and widely adopted technology within the broader LED industry. Key ongoing trends influencing such components include:

• Further Miniaturization: While the 95-21 package is small, even smaller chip-scale package (CSP) LEDs are emerging for ultra-compact designs.
• Increased Efficiency: Continuous improvements in epitaxial growth and chip design lead to higher luminous efficacy (more light output per electrical watt), allowing for lower drive currents and reduced power consumption.
• Enhanced Reliability and Lifetime: Improvements in packaging materials and thermal management are extending operational lifetimes, making LEDs suitable for more critical applications.
• Integration: Trends include integrating multiple LED chips (RGB) into a single package or combining the LED with a driver IC for simplified system design.
• Stricter Compliance: Environmental regulations like RoHS and REACH continue to evolve, pushing manufacturers towards even cleaner material sets and processes.

This datasheet reflects a reliable, standardized component that sits at the intersection of these trends, offering a balance of performance, size, cost, and compliance for a vast array of electronic products.