15 Interesting 555 Timer Projects and Circuits

In this list, we present a collection of exciting 555 Timer Projects that harness the power of the 555 Timers to create a diverse range of electronic devices and circuits.

The standard 555 timer IC is used in a variety of timer, pulse generation, and oscillator applications. It can be used to provide time delays as oscillators and as flip-flop elements.

The 555 timer IC is an integral part of electronics projects. Be it a simple 555 timer-based project involving a single 8-bit microcontroller and some peripherals or a complex one involving system on chips (SoCs), a 555 timer is involved.

1. Motion Detector Using NE555 Timer

This circuit is based on a passive infrared (PIR) sensor, which automatically switches on a device when someone comes close to it. It can be used for the detection of theft or an unauthorized person entering a restricted area or building.

It can also turn on lights when someone approaches the area where it is installed. Applications of this circuit include security systems, corridor lights, and bathroom lights among others.

This 555 timer project is available at Motion Detector using NE555 Timer.

2. Sound Operated Timer

This sound-operated timer is based on LM324 quad-operational amplifier and NE555 timer. Time delay can be set from a few seconds to 30 minutes. It can also be used as a sound-sensitive burglar alarm. A single-side PCB layout for the sound-operated timer and its component layout is also provided.

This project is available at Sound Operated Timer.

3. Set Up a 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%. In this tutorial, the presenter will demonstrate how to set up a 555 timer circuit in monostable mode.

This will allow an LED to be turned on for a specific duration after pressing a button. The time the LED stays on can be changed by changing the resistance and capacitance in the circuit.

This project is available at: Set up a 555 timer in monostable mode.

4. 555 Timer-based PWM Audio Amplifier

This PWM audio circuit employs the 555 timer IC in an astable mode where the switching frequency can be varied from 65 kHz to 188 kHz.

This project is available at 555 timer PWM audio amplifier.

5. Sequential Timer for DC Motor Control

The sequential timer is a widely used circuit in industrial plants because most industrial processes are chain reaction types. That means as one process ends, it triggers the next.

This project is available at Sequential timer for DC motor control.

6. Touch-Free Switch – 555 Timer Project

This type of infrared proximity circuit is widely used as an electric switch where physical contact is not desired for hygiene purposes. For example, we commonly see the use of infrared proximity sensors on public drinking fountains and in public washrooms.

The simple circuit presented here can be operated by moving your hand in front of it. This is achieved by detecting the infrared light reflected by your hand onto a receiver device.

This project is available at Touch free timer switch.

7. Linear Timer for General Use

This simple timer can be used to control any electrical appliance that needs to be switched off after a certain time provided the relay-switch parameters meet the requirements of that appliance.

It uses low-cost components and combines digital precision with simple analog control, providing long timing duration without the use of high-value resistors or capacitors.

This project is available at Linear Timer for General Use.

8. Infrared Remote Control Timer

Presented here is an infrared remote-controlled timer circuit. The circuit comprises two sections, namely, the transmitter section and the receiver section.

This project is available at Infrared Remote control timer.

9. Programmable Industrial On-Off Timer With RF Remote

Some of the features of programmable industrial on/off timers presented here include:

1. Time set from 1 to 60 seconds (can be extended)
2. ‘On’ time and ‘Off’ time can be programmed (from 1 to 60 seconds)
3. Repeat (continuous) and single operation
4. Fully remote-controlled within a 100-meter range
5. User-friendly front-panel controls and display panel with LCD
6. Emergency stop buttons (on the control panel as well as on the remote)
7. Provision of potential-free relay contacts for connecting any 230VAC at 10A or 28V DC at 10A device/application

This project is available at Programmable Industrial On-Off Timer.

10. Speed Checker for Highways

This speed checker can come in handy for the highway traffic police. It will not only provide a digital display in accordance with a vehicle’s speed but also sound an alarm if the vehicle exceeds the permissible speed for the highway.

This 555 timer-based project is available at Speed Checker for Highways.

11. Signal Generator and Inverter Using NE555 Timers

Often we require a square wave signal generator with adjustable frequency, almost equal high and low output pulses, and adjustable amplitudes. Here we present a simple, useful, and low-cost signal generator built around NE555 timers.

Using external switches, you can control or select frequency ranges as per your requirements. However, the use of frequencies below 30kHz is recommended.

This 555 timer project is available at Signal Generator and Inverter Using NE555 Timers

12. 555 Timer-based Astable Multivibrator

We present here a demo program for a 555 timer-based astable multivibrator, which is implemented using the graphical user interface (GUI) in MATLAB 2014 environment

This 555 timer project is available at the 555 timer-based astable multivibrator using MATLAB

13. AC Lamp Blinker Using Timer 555

Here we use a very simple and low-cost timer NE555 to switch on and off two output loads alternately for audio and visual indications. You can achieve this by using a bipolar-transistor-based NE555 or CMOS-based LMC555.

This circuit can be made to blink AC lamps at a low frequency, or switch on and off electrical loads connected to the mains at a low speed. In order to reduce RF emissions, switching is done only at zero crossings of the main AC voltage.

This 555 timer project is available at AC Lamp Blinker Using Timer 555

14. RGB Bulb Using NE555 Timer

Red-green-blue (RGB) multi-color bulbs available in the market are expensive as these are based on a microcontroller. The program for the microcontroller is difficult to understand. Here is a simple and inexpensive circuit for an RGB bulb using a 555 timer.

This 555 timer project is available at RGB Bulb Using NE555 Timer

15. False Triggering Eliminator

Normally, false triggering of timer IC 555 takes place during power on, resulting in unwanted output, which starts the timer’s time cycle. The circuit becomes inefficient especially when the load has to be energized only when desired. Here is a simple false triggering eliminator circuit for timer 555.

This 555 timer project is available at False Triggering Eliminator using Timer 555

Check out our other collection of electronics projects.

This list of 555 Timer Projects was first published on 5 November 2017 and recently updated on August 2023.