information and description about ic 555 smoke detector

This home smoke detector circuit warns the user against fire.
It is based on the smoke that is produced in the event of a fire and runs between the bulb and the range of light, the amount of light falling on the LDR is reduced. This type of circuit is called an optical smoke detector. Do not use it as a home smoke detector is the law for electronic projects.

This causes resistance to LDR to enlarge and voltage on the base of the transistor is pulled high the power directly to the COB (chip-on-board) has been completed. the sensitivity of the smoke detector depends on the distance between the lamp and the range of light, as well as the installation of the specified VR1. Thus, by placing the bulb and LDR at appropriate distances, you can vary the preset VR1 to obtain optimum sensitivity.
We do not build this smoke detector alarm.
With this photoelectric smoke detector circuit can be designed in a very simple and low power signal smoke detector project, which is based on the RE46C190 smoke detector IC. With a minimum of external components, alarms, smoke detectors, it will provide all the necessary functions for use in electronic photoelectric smoke detector project.

Design includes gain on choosing photos amplifier for use with infra-red emitter detector pairs. internal power generator is triggered to smoke detection every 10 seconds to keep the current backup to a minimum. If smoke is detected, the frequency is increased to check the status of the alarm.