IR LED 3.8x3.8x2.28mm 850nm 2W EMC Package - Forward Voltage 1.8V - Radiant Flux 800mW - English Datasheet

1. Product Overview

The RF-E38A8-IR3-FR is an infrared LED designed for high-reliability applications. It uses an EMC (Epoxy Molding Compound) package, offering robustness and efficient thermal management. With a compact size of 3.80mm × 3.80mm × 2.28mm, it fits into various compact optical designs. The LED emits at a peak wavelength of 850nm, making it ideal for security surveillance, infrared illumination, and sensor systems. It is RoHS compliant and moisture sensitive level 3.

2. Technical Parameters In-Depth Analysis

2.1 Electrical and Optical Characteristics (at Ts=25°C)

The device operates with a forward voltage (VF) typically 1.8V and maximum 2.3V at 1000mA forward current (IF). Reverse current (IR) is limited to 10µA at VR=5V. The total radiant flux (Φe) is typically 800mW, with a maximum of 1120mW. The viewing angle (2θ1/2) is 80 degrees, providing a wide radiation pattern suitable for area illumination. The peak wavelength is 850nm with a spectral bandwidth of 39nm. Thermal resistance from junction to solder point (RTHJ-S) is 11°C/W, indicating good heat dissipation.

2.2 Absolute Maximum Ratings

Power dissipation (PD) is 2W, forward current (IF) max 1000mA, reverse voltage (VR) max 5V. Electrostatic discharge (ESD, HBM) withstands up to 2000V. Operating temperature range is -40°C to +85°C, storage temperature -40°C to +100°C, junction temperature (TJ) max 125°C. Note that derating based on solder point temperature is required; forward current should be reduced when operating at elevated temperatures.

3. Binning System Explanation

Although the datasheet does not explicitly detail bin codes, label specifications include fields for BIN CODE, total radiant flux (Φe), peak wavelength (WLP), and forward voltage (VF). This indicates the product is sorted by these parameters. Typical binning categories include flux bins (e.g., R, S, T) and voltage bins (e.g., V1, V2). Wavelength tolerance is typically ±5nm around 850nm. Customers should refer to order codes for specific bin requirements.

4. Performance Curve Analysis

4.1 Forward Voltage vs. Forward Current

The I-V curve shows forward current rising from ~200mA at 1.5V to 1000mA at approx 1.8V. The slope indicates typical diode forward characteristics with dynamic resistance around 0.3-0.4Ω in the operating region.

4.2 Forward Current vs. Relative Intensity

Relative intensity increases nearly linearly with forward current from 200mA to 1000mA. At 1000mA the output is approximately 100% (normalized), with slight saturation at higher currents. This linearity simplifies current control designs.

4.3 Temperature Dependence

Relative intensity decreases with increasing solder point temperature. At 85°C, the intensity drops to about 80% of the value at 25°C. Thermal management is critical for maintaining consistent light output in high-temperature environments.

4.4 Spectrum Distribution

The spectral emission is centered at 850nm with a full width at half maximum (FWHM) of about 39nm. The curve is symmetrical, typical for GaAs-based infrared LEDs. There is negligible emission outside the range of 780-950nm.

4.5 Radiation Pattern

The radiation diagram shows a Lambertian-like distribution with half-angle of 80 degrees. Relative intensity is above 50% from -40° to +40°, making the LED suitable for wide-angle illumination applications.

4.6 Forward Current Derating

Maximum forward current must be derated linearly from 1000mA at 25°C to 0mA at 125°C. This curve is essential for thermal design; in practice at 85°C the allowed current is approximately 600mA.

5. Mechanical and Packaging Information

5.1 Package Dimensions

The LED has a cavity package with dimensions 3.80mm (length) × 3.80mm (width) × 2.28mm (height). Polarity is indicated by a notch on the top view: two anodes (pins 1 and 2) and one cathode (pin 3) on the bottom view. The recommended soldering pad layout includes a 2.7mm by 2.7mm central pad for heat dissipation.

5.2 Carrier Tape and Reel

Packaging is in 12mm wide carrier tape with 4mm pitch, 3000 pcs per reel. The reel dimensions comply with standard EIA-481: flange diameter 330.2mm, hub diameter 79.5mm. Tape includes polarity marks.

6. Soldering and Assembly Guidelines

6.1 Reflow Soldering Profile

Follow JEDEC J-STD-020 lead-free reflow profile. Preheat from 150°C to 200°C for 60-120 seconds, ramp-up rate ≤3°C/s, time above 217°C (TL) up to 60 seconds, peak temperature 260°C (max 10 seconds at 260°C). Cooling rate ≤6°C/s. Do not exceed two reflow passes; if interval exceeds 24 hours, baking before soldering is required.

6.2 Hand Soldering and Repair

Hand soldering: iron temperature <300°C, duration <3 seconds, only once. Repair not recommended; if necessary, use a dual-head soldering iron and pre-validation of LED characteristics.

6.3 Storage and Moisture Handling

Moisture sensitive level 3. Store unopened bags at ≤30°C/≤75%RH for up to 1 year. After opening, use within 168 hours (≤30°C/≤60%RH) or bake at 60±5°C for >24 hours before use. Do not use if desiccant is expired or bag is damaged.

7. Packaging and Ordering Information

Standard packaging: 3000 pcs per reel. Reels are sealed in moisture barrier bag with silica gel and humidity indicator. Label includes part number, lot number, bin codes, quantity, and date code. Outer cartons contain multiple reels.

8. Application Recommendations

8.1 Typical Applications

Surveillance cameras, IR illumination for security, machine vision systems, proximity sensors, and optical data transmission. The 850nm wavelength is well matched to CMOS/CCD cameras.

8.2 Design Considerations

Thermal management: use adequate PCB copper area and thermal vias. Never exceed absolute maximum ratings. Always include a current-limiting resistor or constant current driver to prevent thermal runaway. Avoid reverse voltage. Protect LEDs from electrostatic discharge using proper grounding and handling. Avoid exposure to sulfur, bromine, chlorine compounds above specified limits. Do not apply mechanical stress to the silicone lens.

8.3 Cleaning

Isopropyl alcohol is recommended for cleaning. Do not use solvents that may attack the package. Ultrasonic cleaning is not recommended as it may damage internal wire bonds.

9. Technical Comparison with Competing Products

Compared to standard 5mm IR LEDs, the EMC package offers superior power handling (2W vs typical 100mW) and better thermal management. Competing mid-power infrared emitters in similar SMD packages (e.g., 3.5x3.5mm) often have lower radiant flux (500-700mW) or wider viewing angle (120°). The 80° beam angle of this device provides better collimation for long-range illumination. The low forward voltage (1.8V) reduces power losses in driver circuits.

10. Frequently Asked Questions (FAQ)

Q1: Can I drive this LED at 2A?
No, absolute maximum forward current is 1000mA. Exceeding this will cause overheating and permanent damage.

Q2: What is the recommended drive current for best efficiency?
Efficiency (radiant flux vs. input power) is generally optimal around 500-800mA. Consult the forward current vs. relative intensity curve.

Q3: Is the LED suitable for continuous operation?
Yes, provided thermal management maintains junction temperature below 125°C. Pulse operation with duty cycle less than 10% and short pulse width (0.1ms) can achieve higher peak currents.

11. Practical Application Cases

Case 1: CCTV night vision illuminator
Array of 4 LEDs, each driven at 700mA, total power ~5W, provides illumination for 20-meter field of view. Proper heatsink keeps temperature rise below 30°C.

Case 2: Industrial machine vision strobe
Two LEDs in series, pulsed at 1A with 1% duty cycle, synchronized with camera trigger. Achieves high intensity for high-speed inspection.

12. Operating Principles

Infrared LEDs are based on direct bandgap semiconductors (AlGaAs or GaAs). When forward biased, electrons recombine with holes in the active region, emitting photons with energy corresponding to the bandgap (~1.46 eV for 850nm). The EMC package houses the chip on a metallic leadframe for heat extraction. The silicone lens enhances extraction efficiency and shapes the radiation pattern.

13. Development Trends

The market trends toward higher power densities (2W and above) in compact SMD packages for space-constrained applications. Improvements in phosphor-free infrared technology focus on higher conversion efficiency and better thermal reliability. Multi-chip arrays and integrated optics are emerging to meet diverse illumination needs. This product aligns with the trend of miniaturization and high performance for security and industrial sensing.