Infrared MIDLED HIR89-01C/1R Datasheet - 3.0x2.8x1.9mm - 1.55V - 850nm - 100mW - English Technical Document

1. Product Overview

The HIR89-01C/1R is a miniature surface-mount infrared (IR) emitting diode utilizing the MIDLED package. Its primary function is to emit infrared light at a peak wavelength of 850 nanometers (nm), which is spectrally optimized for compatibility with silicon photodiodes and phototransistors. This makes it a fundamental component in various non-visible light sensing and communication systems.

The device is constructed with a GaAlAs (Gallium Aluminum Arsenide) chip material, housed in a water-clear lens package. Key design advantages include a low forward voltage, which contributes to energy efficiency, and a relatively narrow 30-degree viewing angle, allowing for directed IR emission. The product adheres to modern environmental and safety standards, being Pb-free, compliant with EU REACH regulations, and classified as Halogen-Free.

1.1 Core Features and Compliance

• Electrical Efficiency: Low forward voltage characteristics.
• Optical Performance: 30° typical viewing angle for directed emission.
• Environmental Compliance: Lead-free (Pb-free) construction.
• RoHS Compliance: The product conforms to the Restriction of Hazardous Substances directive.
• REACH Compliance: Meets the requirements of the EU Registration, Evaluation, Authorisation and Restriction of Chemicals regulation.
• Halogen-Free: Contains very low levels of bromine (Br) and chlorine (Cl), specifically Br <900 ppm, Cl <900 ppm, and Br+Cl < 1500 ppm.

2. Technical Specifications 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.

• Continuous Forward Current (I_F): 65 mA
• Peak Forward Current (I_FP): 200 mA (Pulse Width ≤500μs, Duty Cycle ≤5%)
• Reverse Voltage (V_R): 5 V
• Operating Temperature (T_opr): -40°C to +100°C
• Storage Temperature (T_stg): -40°C to +100°C
• Soldering Temperature (T_sol): 260°C (for ≤5 seconds)
• Power Dissipation (P_d): 100 mW (at or below 25°C ambient temperature)

2.2 Electro-Optical Characteristics

These parameters are measured at a standard ambient temperature of 25°C and define the device's performance under typical operating conditions.

• Radiant Intensity (I_e): 40 to 125 mW/sr (measured at I_F=70mA, 20ms pulse). The device is binned into ranks (C: 40-80 mW/sr, D: 63-125 mW/sr).
• Peak Wavelength (λ_p): 850 nm (typical, at I_F=100mA).
• Spectral Bandwidth (Δλ): 30 nm (typical, at I_F=100mA).
• Forward Voltage (V_F):
  • 1.40V to 1.70V (at I_F=20mA)
  • 1.55V to 1.90V (at I_F=70mA, 20ms pulse)
• Reverse Current (I_R): 10 μA maximum (at V_R=5V).
• Viewing Angle (2θ_1/2): 30° (typical, at I_F=20mA).

3. Performance Curve Analysis

The datasheet provides several characteristic curves essential for circuit design and thermal management.

3.1 Forward Current vs. Ambient Temperature

This graph illustrates the derating of the maximum allowable continuous forward current as the ambient temperature increases. The current rating decreases linearly from 65mA at 25°C to lower values as temperature approaches the maximum operating limit of 100°C. Designers must use this curve to ensure the LED is not overdriven in high-temperature environments.

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

The I-V curve shows the exponential relationship typical of diodes. It is crucial for selecting the appropriate current-limiting resistor. A small increase in voltage beyond the typical V_F can lead to a large, potentially destructive increase in current, highlighting the necessity of a series resistor.

3.3 Radiant Intensity vs. Forward Current

This curve demonstrates that the optical output (radiant intensity) increases with forward current, but the relationship is not perfectly linear, especially at higher currents. It helps designers choose an operating point that balances brightness with efficiency and device longevity.

3.4 Spectral Distribution

The spectral plot confirms the emission is centered at 850nm with a typical full width at half maximum (FWHM) of 30nm. This narrow bandwidth ensures good matching with the peak sensitivity of silicon-based detectors.

3.5 Relative Radiant Intensity vs. Angular Displacement

This polar plot visually defines the 30° viewing angle, showing how the intensity drops to half its peak value at ±15° from the central axis. This information is vital for optical system design, determining beam spread and alignment requirements.

4. Mechanical and Package Information

4.1 Package Dimensions

The HIR89-01C/1R uses a compact MIDLED surface-mount package. Key dimensions (in millimeters) are:

• Overall Length: 3.0 mm
• Overall Width: 2.8 mm
• Overall Height: 1.9 mm
• Lead Spacing: 2.0 mm

Tolerances for unspecified dimensions are ±0.1mm. A detailed dimensioned drawing is provided in the datasheet for PCB footprint design.

4.2 Polarity Identification

The cathode is identified on the package. The datasheet includes a diagram showing the cathode marker, which is essential for correct orientation during assembly to prevent reverse bias connection.

4.3 Carrier Tape Dimensions

The device is supplied on embossed carrier tape for automated pick-and-place assembly. The tape dimensions are specified to be compatible with standard SMT equipment. Each reel contains 2000 pieces.

5. Soldering and Assembly Guidelines

5.1 Reflow Soldering Profile

A recommended Pb-free reflow soldering temperature profile is provided. Key parameters include:

• Preheat and soak zone.
• Peak temperature not exceeding 260°C.
• Time above liquidus (typically 217°C).
• Cooling rate.

Reflow soldering should not be performed more than two times.

5.2 Hand Soldering

If hand soldering is necessary, extreme care must be taken:

• Use a soldering iron with a tip temperature < 350°C.
• Limit soldering time per terminal to ≤ 3 seconds.
• Use an iron with a power rating ≤ 25W.
• Allow a minimum 2-second interval between soldering each terminal to prevent thermal shock.

5.3 Rework and Repair

Repair after soldering is strongly discouraged. If unavoidable, a double-head soldering iron must be used to simultaneously heat both terminals, minimizing stress on the LED package. The effect on device characteristics must be verified after any rework.

6. Storage and Handling Precautions

6.1 Moisture Sensitivity

The LED is moisture-sensitive. Precautions include:

• Do not open the moisture-proof barrier bag until ready for use.
• Store unopened bags at ≤ 30°C and ≤ 90% Relative Humidity (RH).
• Use within one year of shipment.
• After opening, store at ≤ 30°C and ≤ 70% RH.
• Complete soldering within 168 hours (7 days) of opening the bag.
• If the storage time is exceeded or the desiccant indicates moisture ingress, bake the components at 60 ±5°C for 24 hours before use.

6.2 Current Protection

Critical: An external current-limiting resistor is mandatory. The LED's exponential I-V characteristic means a small voltage increase can cause a large current surge, leading to immediate burnout. The resistor value must be calculated based on the supply voltage and the desired forward current, considering the V_F range.

7. Packaging and Ordering Information

7.1 Packing Procedure

The LEDs are packed in an aluminum moisture-proof bag containing desiccant. The bag is labeled with critical information.

7.2 Label Specification

The label includes fields for:

• CPN (Customer's Part Number)
• P/N (Manufacturer's Part Number: HIR89-01C/1R)
• QTY (Quantity)
• CAT (Ranks, e.g., C or D for radiant intensity)
• HUE (Peak Wavelength)
• LOT No. (Traceability lot number)
• Production Origin
• Moisture Sensitivity Level (MSL)

7.3 Device Selection Guide

The HIR89-01C/1R is the sole part number in this series, featuring a GaAlAs chip and a water-clear lens.

8. Application Suggestions and Design Considerations

8.1 Typical Applications

• Infrared Sensing Systems: Proximity sensors, object detection, touchless switches.
• Optical Encoders: Position and speed sensing in motors.
• Data Transmission: Short-range IR data links (e.g., remote controls, IrDA).
• Machine Vision: Illumination for cameras with IR filters.
• Security Systems: Active illumination for night-vision cameras.

8.2 Circuit Design Notes

1. Current Limiting: Always use a series resistor. Calculate using R = (V_supply - V_F) / I_F. Use the maximum V_F from the datasheet to ensure safe current under all conditions.
2. Drive Circuit: For pulsed operation (e.g., sensing, communication), ensure pulse width and duty cycle stay within the I_FP ratings to avoid overheating.
3. Thermal Management: Consider the derating curve. In high ambient temperatures or when mounted on a board with other heat-generating components, reduce the operating current accordingly.
4. PCB Layout: Follow the recommended land pattern from the dimension drawing. Ensure adequate spacing from other components to avoid thermal or optical interference.

9. Technical Comparison and Positioning

The HIR89-01C/1R positions itself as a general-purpose, reliable infrared emitter in a miniature SMD package. Its 850nm wavelength is the industry standard for compatibility with silicon detectors. Compared to older through-hole IR LEDs, its SMD format enables smaller, automated PCB assembly. The 30° viewing angle offers a good balance between beam concentration and alignment tolerance for many applications. The provision of detailed binning (C and D ranks) allows designers to select devices based on required output power, which can be critical for achieving consistent sensing range or signal strength.

10. Frequently Asked Questions (Based on Technical Parameters)

10.1 Why is a current-limiting resistor absolutely necessary?

The LED's diode characteristic has a very low dynamic resistance once the forward voltage is exceeded. Without a resistor, the current is only limited by the power supply's internal resistance and wiring, which is typically very low, leading to catastrophic overcurrent. The resistor provides a linear, predictable, and safe method to set the operating current.

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

No. Microcontroller GPIO pins have current sourcing/sinking limits (often 20-40mA) that are at or below this LED's continuous rating. More importantly, they cannot provide the necessary current limiting. You must use the GPIO to control a transistor or MOSFET, which then drives the LED through an appropriate current-limiting resistor connected to the main power rail.

10.3 What is the difference between the C and D rank bins?

The C and D ranks specify different ranges of Radiant Intensity (I_e) measured at 70mA. The C rank has a lower output range (40-80 mW/sr), while the D rank has a higher output range (63-125 mW/sr). Selecting a D rank device can provide more optical power for longer range or more robust signal detection, but may come at a slightly higher cost. The specific rank ordered will be indicated on the package label.

10.4 How critical are the moisture sensitivity and baking instructions?

Very critical. Moisture absorbed into the plastic package can vaporize during the high-temperature reflow soldering process, causing internal delamination, cracking, or "popcorning," which can damage the die or wire bonds. Following the storage times and performing the bake-out procedure when required is essential for high assembly yield and long-term reliability.

11. Design and Usage Case Study

11.1 Designing a Simple Proximity Sensor

Objective: Detect an object within 10cm.
Design: Pair the HIR89-01C/1R with a matching silicon phototransistor. The LED is driven by a 5V supply through a current-limiting resistor. Using the typical V_F of 1.55V at 70mA, the resistor value is R = (5V - 1.55V) / 0.07A ≈ 49.3Ω (use a standard 51Ω resistor). The LED is pulsed at a specific frequency (e.g., 38kHz) using a microcontroller. The phototransistor's output is connected to a demodulating receiver IC tuned to the same frequency. This design rejects ambient light, and an object's presence is detected by the reflected modulated IR light. The 30° beam helps define the detection zone.

12. Operational Principle

An Infrared Light Emitting Diode (IR LED) operates on the principle of electroluminescence in a semiconductor p-n junction. When a forward voltage is applied, electrons from the n-type region and holes from the p-type region are injected across the junction. These charge carriers recombine in the active region (the GaAlAs layer in this case). The energy released during recombination is emitted as photons (light). The specific bandgap energy of the GaAlAs semiconductor material determines the wavelength of the emitted photons, which for this device is centered in the near-infrared spectrum at 850nm. The water-clear epoxy lens shapes the emitted light into the specified viewing angle.

13. Technology Trends

Infrared LED technology continues to evolve. Trends include:

• Higher Efficiency: Development of new semiconductor materials and structures (e.g., multi-quantum wells) to achieve more optical power output per unit of electrical input (higher wall-plug efficiency).
• Increased Power Density: Devices capable of handling higher drive currents in smaller packages for applications like LiDAR and long-range sensing.
• Multi-Wavelength and VCSELs: Emergence of LEDs and Vertical-Cavity Surface-Emitting Lasers (VCSELs) at other IR wavelengths (e.g., 940nm for better eye safety, 1350nm/1550nm for longer-range LiDAR) to suit specific application needs.
• Integrated Solutions: Combining the IR emitter, driver circuitry, and sometimes the detector into a single module to simplify design and improve performance.

The HIR89-01C/1R represents a mature, cost-effective, and reliable solution for a wide array of mainstream IR applications.