SD2 Smoke Detector

This smoke detector circuit diagram is based on the SD2 CMOS Photo-Electric Smoke Detector Integrated Circuit manufactured by Supertex INC and include almost all needed components to build a very simple and high efficiency smoke detector project .As you can see , this smoke detector circuit diagram is very simple an require few external components .

SD2 Smoke Detector Circuit diagram

The LED predriver output pulses an ex­ternal transistor which in turn, switches on the infrared light emitting diode at a very low duty cycle. The desired IR LED pulse period is determined by the value of the externai timing resistor. The Smoke Sensitivity is adjustable through a trimmer resistor which varies the IR LED puise width. The light sensing element is a silicon photovoltaic cell which is held at near zero bias to minimize leakage currents. The circuit can detect signals as low as 1 mV and generate an alarm. The IR LED pulse repetition rate increases when smoke is detected. The IR diode can be RCA Type SG 1010A or Spectronics Type SE 5455-4 Clairex and the IR Photo detector can be Vactec VTS4085 .

Because the SD2 CMOS Photo-Electric Smoke Detector IC is designed for use in low power, battery operated, consumer applications it needs a 9 volts DC power supply (or a 9 volts battery ).
Share this article

3 comments:

  1. Hi there, I like your blog and it has some pretty valuable information.

    Las Vegas Fire Extinguisher Service

    ReplyDelete
  2. Smoke alarms give a beeping sound increasing in intensity when they detect heat or smoke in its surroundings.

    Where To Get Fire Extinguishers in Las Vegas

    ReplyDelete
  3. Smoke detectors are important safety devices, because of their obvious potential to save lives and property.

    Las Vegas Fire Extinguisher Sales

    ReplyDelete

 
Copyright © 2019 W3circuits.blogspot.com • All Rights Reserved.
back to top