Introduction to Speed Sensor

Here may be a motor speed sensor module, the main goal is to see the speed of an electrical motor. The module is often utilized in association with a microcontroller for motor speed detection, pulse count, position limit, etc. in theory, any rate meter simply measures the speed at which some event occurs. Usually, this is often done by counting the events for a given period of your time (integration interval) then simply dividing the number of events by the time to urge the speed.

Basically, the microcontroller-compatible motor speed sensor module described may be a simple device that yields processed pulse trains when the visual path of its optical sensor is physically interrupted by some kind of slotted wheel or similar mechanism (an optical sensor commonly consists of a LED that gives the illumination and a phototransistor that senses the presence or absence of that illumination). The transmissive optical sensor used here consists of an infrared LED and a phototransistor. This both prevents interference from stray external light sources and by having the 2 components matched for a selected frequency of radiation, they’re even more resistant to undesired interference.

Pinout of Speed Sensor

  • Connect Vcc: 5v power supply.
  • Ground: Ground pin of power supply.
  • Aout:  Analog pin of pic microcontroller.
  • Dout:  Digital pin of pic microcontroller.


Groove type optical coupling sensor the output state light, lamp output level, the output low-level light. covered, output high level Without sunscreen, the output low level. the comparator output signal is clean, good waveform, driving ability is strong, for more than 15 ma. has a fixed bolt hole, convenient installation


  • Groove width 10 mm.
  • the working voltage of 3.3 V to 5 V
  • output form: digital switch output (0 and 1)
  • PCB size: 2.3 cmx2cm
  • use the LM393 wide voltage comparator