📌 Product Overview
💡 The XL-S2008RHIRC is a dual-emitter SMD LED designed for reflective photoplethysmography (PPG) in space-constrained wearable electronics. 🔎 By combining a 660nm Red chip and an 870nm Infrared chip into a single 2.0 x 0.8 x 0.4mm package, it allows optical designers to maximize board real estate while maintaining precise peak wavelengths for blood oxygen saturation (SpO2) and heart rate detection.
⚙️ Typical Applications
This component is optimized for consumer and professional health monitoring devices requiring stable optical performance.
- Pulse Oximeters & SpO2 Modules: Utilizes specific red/IR ratios for accurate oxygen saturation calculation.
- Smart Watches & Fitness Trackers: Enables 24/7 heart rate and sleep monitoring via side-looking integration.
- Medical IoT Devices: suitable for portable health electronics requiring ROHS compliance.
📉 Key Technical Specifications
The following table summarizes the electro-optical characteristics under standard test conditions (Ta=25°C).
| Parameter | Symbol | Red (Min/Typ) | Infrared (Min/Typ) | Unit | Conditions |
|---|---|---|---|---|---|
| Forward Voltage | VF | - / 2.5 | - / 1.7 | V | IF = 20mA |
| Peak Wavelength | λp | 655 / 660 | 850 / 870 | nm | IF = 20mA |
| Optical Power | PO | 8.5 / 10.5 | 6.0 / 7.2 | mW | IF = 20mA |
| Pulse Power | PO | 75 / - | 50 / - | mW | 200mA, 1/10 Duty |
| Half Angle | θ1/2 | - / ±60 | - / ±60 | deg | - |
🚨 Note: Tolerance on radiation intensity is ±15%, and forward voltage tolerance is ±0.1V. Bin sorting is critical for design consistency.
⚡ Absolute Maximum Ratings & Process Limits
Exceeding these limits may cause permanent device failure or significant optical degradation. 👇 Refer to this table for design safety margins.
| Parameter | Symbol | Value | Unit | Notes |
|---|---|---|---|---|
| DC Forward Current | IF | 50 | mA | Per chip |
| Pulse Forward Current | IFP | 200 | mA | 0.5ms width, 1/10 duty |
| Reverse Voltage | VR | 5 | V | - |
| Operating Temp | TOPR | -40 ~ +85 | °C | - |
| Storage Temp | TSTR | -40 ~ +100 | °C | - |
| Soldering Temp | TSOL | 260 | °C | Max 6 seconds |
⚠️ Thermal Warning: High drive currents significantly increase junction temperature; adequate thermal pads are recommended for continuous high-power pulse modes.
📦 Package, Dimensions & Assembly Notes
- Package Type: 2008 Surface Mount Device (SMD)
- Dimensions (LxWxH): 2.0mm x 0.8mm x 0.4mm
- Packaging: EIA standard tape and reel for automated feeders.
- Soldering: Designed for standard reflow soldering processes.
- MSL: Level 3 (Floor life >168 hours at 30°C/60%RH). Ensure baking if moisture barrier bags are exposed beyond limits.
- Assembly: Compatible with high-speed SMT pick-and-place machines.
📦 Sourcing & Supply Considerations
- Supply Chain: Verify stock authenticity through XINGLIGHT authorized channels to avoid inconsistent wavelength bins.
- Sampling: Request engineering samples for pilot runs to validate optical signal-to-noise ratio in your specific housing design.
- Yield Rate: Bin selection (Forward Voltage vs. Optical Power) impacts unit cost; relax tolerances if design permits.
- Procurement: Check lead times for specific wavelength bins to prevent production delays.
❓ Frequently Asked Questions
Q: What are the specific wavelengths of the Red and IR emitters?
A: The Red emitter typically peaks at 660nm, and the Infrared emitter peaks at 870nm (Typical values). These specific wavelengths are standard for absorption-based hemoglobin detection in pulse oximetry.
Q: Can this LED be used for continuous wave (CW) transmission?
A: Yes, but the DC forward current is limited to 50mA. For most SpO2 applications, pulsed operation (e.g., 200mA pulses) is preferred to achieve higher optical power without overheating the component.
Q: What is the Moisture Sensitivity Level (MSL) for this component?
A: The XL-S2008RHIRC is classified as MSL 3. This means it can be exposed to the factory floor environment (≤30°C / 60% RH) for up to 168 hours before baking or reflow soldering is required.
Q: What are the critical soldering limits to prevent damage?
A: The maximum soldering temperature is 260°C for ≤6 seconds. For reflow profiles, ensure the board does not exceed this limit to prevent delamination or optical degradation.
Q: How does the viewing angle affect my sensor design?
A: The Half Viewing Angle is ±60°. This wide angle is suitable for reflective PPG designs where the sensor is placed adjacent to the LED, though light baffles may be required to reduce crosstalk.
Q: Is this component ROHS compliant?
A: Yes, the datasheet explicitly states this is an environmental protection product meeting ROHS requirements, suitable for global markets including the EU.
