SMD Infrared LED 0603 Package - 1.6x0.8x0.8mm - Peak Wavelength 870nm - 65mA - 110mW - Technical Datasheet

1. Product Overview

This document details the specifications for a high-performance, miniature surface-mount infrared (IR) emitting diode. The device is housed in a compact 0603 package, making it suitable for space-constrained applications requiring reliable infrared emission. Its primary function is to emit light in the near-infrared spectrum, with a typical peak wavelength of 870 nanometers (nm), which is optimally matched to the spectral sensitivity of silicon photodiodes and phototransistors. The core material is AlGaAs (Aluminum Gallium Arsenide), known for its efficient infrared light generation.

1.1 Core Advantages and Target Market

The device offers several key advantages for modern electronic design. Its miniature double-ended SMD package allows for high-density PCB mounting and is compatible with automated pick-and-place assembly processes. It is designed to be compatible with both infrared and vapor phase reflow soldering, facilitating modern manufacturing workflows. The product is compliant with major environmental and safety standards, including RoHS (Restriction of Hazardous Substances), EU REACH regulations, and is Halogen-Free (Br <900 ppm, Cl <900 ppm, Br+Cl < 1500 ppm). This combination of small size, performance, and compliance makes it ideal for consumer electronics, industrial sensors, and communication devices.

Primary Applications Include:

• PCB-mounted infrared proximity and presence sensors.
• Infrared remote control units where higher radiant intensity is required.
• Barcode scanners and optical encoders.
• Various infrared-based data transmission and sensing systems.

2. In-Depth Technical Parameter Analysis

A thorough understanding of the electrical and optical parameters is crucial for reliable circuit design and ensuring the LED operates within its safe operating area (SOA).

2.1 Absolute Maximum Ratings

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

• Continuous Forward Current (I_F): 65 mA. Exceeding this current, even momentarily, can cause catastrophic failure due to overheating of the semiconductor junction.
• Reverse Voltage (V_R): 5 V. The LED has a low reverse breakdown voltage. Circuit designs must ensure the LED is not subjected to reverse bias exceeding this value, often requiring protection in AC or bidirectional signal environments.
• Power Dissipation (P_c): 110 mW at 25°C. This is the maximum power the package can dissipate as heat. The actual permissible power decreases as ambient temperature (T_a) increases. Derating is necessary for high-temperature applications.
• Temperature Ranges: Operating: -25°C to +85°C; Storage: -40°C to +100°C.
• Soldering Temperature (T_sol): 260°C for a maximum of 5 seconds. This defines the reflow soldering profile constraints.

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

These are the typical performance parameters under specified test conditions. Designers should use the typical or maximum/minimum values as appropriate for their design margins.

• Radiant Intensity (I_E): 1.3 mW/sr (typical) at I_F=20mA. Radiant intensity measures the optical power emitted per unit solid angle (steradian). It is a key parameter for determining the signal strength at a receiver. The minimum specified value is 1.0 mW/sr.
• Peak Wavelength (λ_p): 870 nm (typical), with a range from 860 nm to 900 nm. This is the wavelength at which the emission spectrum is strongest. Matching this to the peak sensitivity of the receiver (e.g., a silicon photodetector at ~850-950nm) maximizes system efficiency.
• Spectral Bandwidth (Δλ): 45 nm (typical). This is the full width at half maximum (FWHM) of the emission spectrum, indicating the range of wavelengths emitted.
• Forward Voltage (V_F): 1.35 V (typical) at I_F=20mA, ranging from 1.20 V to 1.70 V. This parameter is essential for calculating the current-limiting resistor value: R = (V_supply - V_F) / I_F. The variation must be accounted for in robust designs.
• Reverse Current (I_R): 10 µA (maximum) at V_R=5V.
• Viewing Angle (2θ_1/2): 140 degrees. This is the full angle where the radiant intensity drops to half of its peak value (on-axis). A wide viewing angle is beneficial for applications requiring broad coverage, such as proximity sensors.

3. Performance Curve Analysis

The provided characteristic curves offer valuable insights into the device's behavior under varying conditions, which is critical for real-world application design.

3.1 Forward Current vs. Ambient Temperature

This curve illustrates the relationship between the maximum permissible continuous forward current and the ambient temperature. It demonstrates the necessary derating of the forward current as temperature increases to stay within the power dissipation limit. At temperatures approaching the maximum operating temperature (+85°C), the allowable continuous current is significantly lower than the 65mA absolute maximum rating at 25°C.

3.2 Spectral Distribution

The spectral distribution graph shows the relative radiant power output as a function of wavelength. It confirms the peak wavelength (λ_p) of 870nm and the typical spectral bandwidth (Δλ) of approximately 45nm. The shape of this curve is important for filtering and for ensuring compatibility with the receiver's spectral response.

3.3 Peak Emission Wavelength vs. Ambient Temperature

This curve shows that the peak wavelength has a positive temperature coefficient, meaning it increases slightly with increasing junction temperature. This shift (typically around 0.1-0.3 nm/°C for AlGaAs devices) is important for precision sensing applications where wavelength stability is critical.

3.4 Forward Voltage vs. Ambient Temperature

The forward voltage (V_F) has a negative temperature coefficient; it decreases as temperature increases. This characteristic must be considered in constant-current drive circuits, as a lower V_F at high temperature could slightly affect the power dissipation calculation if using a simple series resistor.

3.5 Relative Radiant Intensity vs. Angular Displacement

This polar plot visually defines the viewing angle (140° at half-intensity points). The radiation pattern is typically Lambertian or near-Lambertian for this package style, which is useful for modeling the irradiance on a target surface at various angles and distances.

4. Mechanical and Packaging Information

4.1 Package Dimensions (0603)

The device conforms to the standard 0603 (1608 metric) footprint: approximately 1.6mm in length, 0.8mm in width, and 0.8mm in height. Detailed dimensional drawings specify pad layout, component outline, and terminal positions with a standard tolerance of ±0.1mm unless otherwise noted. Correct land pattern design is essential for reliable soldering and mechanical stability.

4.2 Polarity Identification

The datasheet includes a diagram indicating the anode and cathode terminals. Correct polarity is mandatory for device operation. Typically, the cathode may be marked by a notch, a green indicator, or a specific pad shape on the tape and reel packaging.

4.3 Tape and Reel Specifications

The product is supplied in 8mm wide embossed carrier tape on 7-inch diameter reels. The carrier tape dimensions are specified to ensure compatibility with standard SMD assembly equipment. Each reel contains 4000 pieces.

5. Soldering and Assembly Guidelines

Proper handling is critical to maintain device reliability and performance.

5.1 Moisture Sensitivity and Storage

The device is moisture-sensitive (MSL). Precautions include:

• Do not open the moisture-proof barrier bag until ready for use.
• Store unopened bags at ≤30°C and ≤90% RH.
• Use within one year of shipment.
• After opening, store at ≤30°C and ≤60% RH.
• Use within 168 hours (7 days) after opening the bag.
• If the storage time is exceeded or the desiccant indicates moisture ingress, bake at 60 ±5°C for a minimum of 24 hours before use.

5.2 Reflow Soldering Profile

A Pb-free reflow soldering profile is recommended. Key parameters include a peak temperature of 260°C, with the time above 240°C not exceeding the recommended limit (implied by the 5-second maximum at 260°C). Reflow soldering should not be performed more than two times to avoid excessive thermal stress on the epoxy package and wire bonds.

5.3 Hand Soldering and Rework

If hand soldering is necessary, use a soldering iron with a tip temperature below 350°C and apply heat to each terminal for no more than 3 seconds. Use a low-power iron (≤25W). Allow a cooling interval of more than 2 seconds between soldering each terminal. For rework, a dual-head soldering iron is recommended to simultaneously heat both terminals and avoid mechanical stress. The feasibility and impact of rework on device characteristics should be verified beforehand.

6. Application Design Considerations

6.1 Current Limiting is Mandatory

An LED is a current-driven device. A series current-limiting resistor is absolutely required. The forward voltage (V_F) has a narrow range, and a small increase in applied voltage beyond V_F causes a large, potentially destructive increase in forward current (I_F). The resistor value is calculated based on the supply voltage (V_supply), the desired forward current (I_F), and the forward voltage (V_F), using the worst-case V_F (minimum) to ensure current does not exceed the design maximum.

6.2 Thermal Management

While the package is small, power dissipation (up to 110mW) generates heat. For continuous operation at high currents or in elevated ambient temperatures, consider the thermal resistance of the PCB. Providing adequate copper area (thermal relief pads) around the solder pads helps dissipate heat and maintain a lower junction temperature, which improves long-term reliability and prevents luminous output degradation.

6.3 Optical Design

The 140-degree viewing angle provides broad emission. For applications requiring a more focused beam, external lenses or reflectors can be used. Conversely, for very wide-area coverage, the native angle may be sufficient. The water-clear lens is suitable for applications where the exact emission point is not critical; if a specific color or diffusion is needed for assembly alignment, this must be considered as the lens does not provide it.

6.4 Circuit Protection

In environments where reverse voltage transients are possible (e.g., inductive loads, hot-plugging), consider adding a protection diode in parallel with the LED (cathode to anode) to clamp any reverse voltage below the 5V maximum rating.

7. Comparison and Selection Guidance

This device is part of a family of IR LEDs. The key selection criteria from the provided guide is the chip material (AlGaAs) and lens color (Water Clear). When selecting an IR LED, engineers must compare key parameters:

• Wavelength (λ_p): Match to the peak sensitivity of the receiver (photodiode, phototransistor, or IC). 870nm is a common standard.
• Radiant Intensity (I_E): Higher intensity provides a stronger signal, allowing for longer range or lower drive current.
• Viewing Angle: A narrow angle provides longer range and more focused light; a wide angle provides broader coverage.
• Package Size: The 0603 package offers a very small footprint for miniaturized designs.
• Forward Voltage: Lower V_F can be advantageous in low-voltage battery-operated circuits.

The primary differentiator of this specific part is its combination of a standard 0603 footprint with a relatively high radiant intensity and wide viewing angle, suitable for general-purpose IR sensing and communication.

8. Frequently Asked Questions (Based on Technical Parameters)

8.1 What is the purpose of the 870nm wavelength?

870nm is in the near-infrared spectrum, invisible to the human eye. It is efficiently detected by inexpensive and common silicon-based photodetectors, which have peak sensitivity around 800-950nm. This makes it ideal for sensing, remote control, and optical isolation applications.

8.2 Can I drive this LED directly from a 3.3V or 5V microcontroller pin?

No. You must use a current-limiting resistor. For example, to drive at I_F=20mA from a 3.3V supply, assuming a typical V_F of 1.35V: R = (3.3V - 1.35V) / 0.020A = 97.5Ω. Use a standard 100Ω resistor. Always verify the current does not exceed the maximum under worst-case V_F conditions.

8.3 How does temperature affect performance?

As temperature increases: Radiant output typically decreases, forward voltage decreases, and peak wavelength increases slightly. For stable operation, design drive circuitry that accounts for these variations, especially if operating over the full -25°C to +85°C range.

8.4 Is a heat sink required?

For continuous operation at the absolute maximum current (65mA) at room temperature, the power dissipation is P = V_F * I_F ≈ 1.35V * 0.065A ≈ 88mW, which is below the 110mW rating. However, at high ambient temperatures, derating is necessary. Good PCB thermal design (copper pads) usually suffices; a separate heat sink is not typical for 0603 packages.

9. Practical Application Example: Simple IR Proximity Sensor

A common use case is a reflective object sensor. The IR LED is placed adjacent to a phototransistor. A microcontroller pulses the LED (e.g., at 20mA). The light reflects off a nearby object and is detected by the phototransistor, whose output is read by the microcontroller. Design steps:

1. LED Drive: Use a GPIO pin and an NPN transistor (or a MOSFET) with a series resistor to pulse the LED at the desired current. Pulsing allows for higher instantaneous current (for stronger signal) while keeping average power low.
2. Receiver Circuit: The phototransistor is connected in a common-emitter configuration with a pull-up resistor to create a voltage output. The value of the collector resistor determines sensitivity and response speed.
3. Optical Considerations: A small barrier between the LED and phototransistor on the PCB helps reduce direct crosstalk. The wide 140° viewing angle of the LED helps illuminate a broad area in front of the sensor.
4. Signal Processing: The microcontroller can use synchronous detection (only reading the receiver during the LED pulse) to reject ambient light interference.

10. Operating Principle and Technology Trends

10.1 Basic Operating Principle

An infrared LED is a semiconductor p-n junction diode. When forward biased, electrons from the n-region recombine with holes from the p-region in the active region (made of AlGaAs). This recombination process releases energy in the form of photons (light). The specific bandgap energy of the AlGaAs material determines the wavelength of the emitted photons, which in this case is in the 870nm infrared range. The water-clear epoxy package encapsulates the chip, provides mechanical protection, and acts as a lens shaping the emission pattern.

10.2 Industry Trends

The trend in SMD infrared LEDs continues toward higher efficiency (more radiant output per unit electrical input), smaller package sizes for greater design flexibility, and increased integration. This includes devices with built-in drivers, modulated output for improved noise immunity, and multi-chip packages combining different wavelengths or combining an emitter and detector in a single package. There is also a strong focus on improving high-temperature performance and reliability for automotive and industrial applications. The device described here represents a mature, reliable, and widely adopted solution within this evolving landscape.