📦 Product Overview
The Photo Interrupter Speed Sensor Module with LM393 is an infrared (IR) optical sensor module that detects objects or interruptions in an IR beam. It uses a transmissive slot-type IR sensor combined with the LM393 voltage comparator to produce a digital output signal, making it ideal for speed, rotation, or object detection in electronics and robotics projects.
Key Features:
Detects rotation speed or object passage.
Clean digital output suitable for microcontrollers (Arduino, ESP32, Raspberry Pi).
Adjustable for different detection distances and sensitivities (depending on module design).
Compact, lightweight, and easy to mount.
📊 Specifications
Parameter Specification
Sensor Type IR Photo Interrupter (Slot / Transmissive)
Main IC LM393 Voltage Comparator
Operating Voltage 3.3 V – 5 V DC (typical)
Current Consumption < 25 mA
Output Type Digital switch output (TTL logic)
Output Drive Capability ~15 mA (suitable for LEDs, small loads)
Slot Width ~5 mm (may vary per module)
Detection Method IR beam interrupted by object
Response Time < 2 ms
Output Logic HIGH when beam is blocked, LOW when clear (may vary)
PCB Size ~32 × 17 mm (approx.)
Mounting 2 × M3 screw holes for stable mounting
Indicator LED YES – indicates when the sensor is triggered
Operating Temperature Standard ambient (–20 °C to +60 °C typical)
🔧 How It Works
The IR LED emits a beam toward a phototransistor.
When the beam is uninterrupted, the phototransistor conducts; when blocked by a rotating disc, object, or flag, conduction stops.
The LM393 comparator converts this analog signal to a clean digital HIGH/LOW output, suitable for reading by microcontrollers.
Applications:
Motor RPM measurement
Wheel encoder / rotation detection
Object counting on conveyor belts
Contactless limit switches
Robotics and automation projects