This project is available at: Set up a 555 timer in monostable mode. The time the LED stays on can be changed by changing the resistance and capacitance in the circuit. This will allow an LED to be turned on for a specific duration after pressing a button. In this tutorial, the presenter will demonstrate how to setup 555 timer circuit in monostable mode. The 555 can act as either a simple timer to generate single pulses for time delays, or as a relaxation oscillator producing stabilized waveforms of varying duty cycles from 50 to 100%. Set Up a 555 Timer Circuit in Monostable Mode This project is available at: Sound Operated Timer. A single side PCB layout for the sound operated timer and its component layout is also provided. It can also be used as a sound sensitive burglar alarm. Time delay can be set from a few seconds to 30 minutes. This sound operated timer is based on LM324 quad-operational amplifier and NE555 timer. This 555 timer circuit is available at: Motion Detector using NE555 Timer. Applications of this circuit include security systems, corridor lights and bathroom lights among others. It can also turn on lights when someone approaches the area where it is installed. It can be used for detection of theft or an unauthorized person entering a restricted area or building. This circuit is based on a passive infrared (PIR) sensor, which automatically switches on a device when someone comes close to it. For the full list of timer-based projects check out 555 timer projects. Here, we take a look at some 555 timer circuits based on the IC. Be it a simple 555 timer project involving a single 8-bit micro-controller and some peripherals or a complex one involving system on chips (SoCs), 555 timer working is involved. The 555 timer IC is an integral part of electronics projects. It can be used to provide time delays, as oscillators and as flip-flop elements. The standard 555 timer IC is used in a variety of timer, pulse generation and oscillator applications.

555 circuit diagram