📌 Product Overview
The XL-ITR8402 is a 940nm Through-Beam Photoelectric Switch designed for SMT assembly. It integrates a high-radiant intensity infrared emitter and a high-sensitivity phototransistor detector into a single compact package. This component is specifically engineered for non-contact object detection in consumer electronics and small industrial automation.
For engineering teams, the critical selection variables are the 940nm peak wavelength (minimizing visible light interference) and the fast response time (tr/tf ≤ 15μs), which ensures reliable switching in high-speed applications like coin validators or encoder wheels. 💡 It provides a cost-effective sensing solution while maintaining a low 1.2V forward voltage drive.
🔍 Typical Applications & Design Context
Based on its electrical characteristics and form factor, the XL-ITR8402 is best suited for:
- 📉 Slot Machines & Coin Counters: The high radiant intensity and 940nm wavelength provide reliable detection through narrow slots, rejecting ambient visible light interference.
- 🏠 Small Home Appliances: Ideal for safety interlocks (e.g., lid closure detection) in coffee makers or air purifiers due to its low power consumption.
- 🖨️ Office Automation (Scanners/Fax): The fast response time allows for accurate paper edge detection and speed sensing.
- ⚙️ Automatic Sensors: Used for simple position detection in compact mechanical assemblies where space is at a premium.
📊 Key Technical Specifications
The following table highlights the performance windows under standard test conditions (Ta=25°C). ⚠️ Designers should focus on the Forward Voltage (VF) and Collector Current (IC) ranges to ensure circuit compatibility.
| Parameter | Symbol | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| Peak Wavelength | λP | IF = 20mA | - | 940 | - | nm |
| Forward Voltage | VF | IF = 20mA | - | 1.2 | 1.6 | V |
| Collector Current | IC(ON) | IF=20mA, VCE=5V | 0.5 | 10 | - | mA |
| Rise Time | tr | VCE=5V, RL=1kΩ | - | 15 | - | μs |
| Fall Time | tf | VCE=5V, RL=1kΩ | - | 15 | - | μs |
⚡ Absolute Maximum Ratings & Process Limits
Exceeding these ratings causes permanent damage. 👇 The Moisture Sensitivity Level (MSL) is a critical supply chain factor often overlooked in design.
| Parameter | Symbol | Ratings | Unit | E-E-A-T Validation Insight |
|---|---|---|---|---|
| Power Dissipation | PD | 75 | mW | 💡 Thermal Design: Ensure PCB copper pours act as heatsinks to prevent derating at high ambient temps. |
| Forward Current (Cont.) | IF | 50 | mA | ⚠️ Drive Limit: Do not exceed 50mA continuous drive; use pulsed mode (max 1A) for higher intensity. |
| Reverse Voltage | VR | 5 | V | 🔒 Protection: Reverse voltage >5V will destroy the emitter. Add reverse protection if inductive kickback is possible. |
| Soldering Temp | Tsol | 260 | °C | 🔥 SMT Process: Max 260°C for 5 seconds. Exceeding this degrades the epoxy lens. |
| MSL Level | - | 2 | - | 🚨 Supply Chain Risk:MSL 2 means components must be mounted within 1 year of bag sealing. Floor life >1 year requires baking (125°C for 24hrs) to prevent "popcorning" cracks during reflow. |
🏗️ Package, Dimensions & Assembly Notes
- Package Form: Standard Through-Beam Photoelectric Switch style (check specific drawing "Outline Dimension" in full datasheet for pin pitch).
- Tolerance: Mechanical dimensions are typically ±0.3mm unless noted.
- Soldering: Manual soldering is allowed but keep the iron tip >2mm from the epoxy body (lens) to prevent thermal stress clouding the lens.
- Cleaning: Use mild solvents; aggressive alcohol cleaning may crack the epoxy or damage the marking.
🛒 Procurement & Sourcing Insights
💡 Alternative Evaluation: When replacing the XL-ITR8402, the critical matching parameter is often the Voltage Grading Code (e.g., R2-4) and Current Transfer Ratio (IC). Substituting with a lower sensitivity part will reduce the detection range.
- Supply Chain Risk: "Gray market" stock often has high moisture content. Always verify the date code and MSL seal integrity upon receipt.
- Validation Tip: If cross-referencing to a major brand (like Everlight or Sharp), ensure the Collector-Emitter Voltage (VCEO) matches; some industrial alternatives require 30V+ rating which this part supports.
- Lead Time: SMD IR sensors typically have stable lead times, but fluctuations in raw epoxy materials can impact availability.
❓ FAQ
Q: Can I use a standard resistor to drive the emitter side?
A: Yes, but ensure the current does not exceed 50mA continuous. For longer detection distances, design a driver circuit that utilizes the 1A pulsed current capability (pulse width ≤100μs, duty cycle 1%) to boost radiant intensity without overheating the component.
Q: What happens if I store the components for too long before assembly?
A: Since this is an MSL 2 rated device, prolonged storage (beyond 1 year from seal) or exposure to humid air introduces moisture into the package. During SMT reflow, this moisture expands rapidly (popcorning), cracking the package or delaminating the internal die. 🔒 You must bake the reels before use.
Q: Is the 940nm wavelength visible to the human eye?
A: No, 940nm is infrared (IR) and invisible. However, a very faint red glow might be seen at extreme currents due to secondary harmonics, but it is generally safe for applications where visible light distraction is a concern.
Q: How do I verify the authenticity of XINGLIGHT components?
A: Verify the packaging date code against the seal integrity. Counterfeit components often have inconsistent laser marking on the top of the lens. Always source from authorized franchises or verified distributors like LDeepAI to ensure valid MSL certification.
