Light Dimmer Using 555 Timers 482u5f

LIGHT DIMMER USING 555 TIMERS ABSTRACT One of the most fundamental problems when it comes to usage of dc light is their Intensity control which can be overcome by our device. The main focus of this project is to design a system that can control the DC Light Intensity using 555 timers, so thar we can save the power. The most common method of Intensity control is PWM or pulse width modulation. Pulse width modulation is the process of switching the power to a device on and off at a given frequency, with varying on and off times. These on and off times are referred to as duty cycle. A 10% duty cycle signal is on for 10% of the wavelength and off for 90%, while a 90% duty cycle signal is on for 90% and off for 10%. These signals are sent to the light at a high enough frequency that the pulsing has no effect on the light. The end result of the PWM process is that the overall power sent to the light can be adjusted from off (5% duty cycle) to full on (100% duty cycle) with good efficiency and stable control. This system consists of a potentiometer, 555 timer and LED’s. Since it is already stated above that PWM is the most common method of intensity control. Therefore, PWM signals are generated by the 555 timer. The DC Light Intensity can be controlled by the duty cycle of that signal. If the duty cycle is changed, the Intensity of the LED gets changed. The duty cycle is changed using a potentiometer by varying the resistance value. Main Objective of the project: 1. LED Intensity control using potentiometer 2. To get to know about the configuration of 555 timer to produce PWM signals Learning’s: 1. Power Supply 2. 555 Timer 3. Potentiometer 4. Working principle of LED’s and Intensity Control.

Building Blocks: 1. Regulated Power Supply 2. Potentiometer 3. 555 Timer 4. DC Light/LED’s. 5. Resistors and Capacitors for the timer Block Diagram:

Regulated Power Supply

555 Timer Potentiometer

DC Light/LED’s

Resistor & Capacitor Components