PWM using 555.
A simple oscilator with PWM that can be used to control speed of motors or light intensity. (4/29/2006)
Source: http://www.josepino.com/?pwm Tags: electronics
circuits
Pulse width modulation (PWM) is a technique to control analog circuits with a digital output. PWM is used in many applications, Specially to control light intensity and speed on motors.
A PWM circuit makes a square wave with a variable width. The pulse width in this circuit can be varied from 5% to 95%. Used in a dimmer, this circuit controls the light intensity according the pulse width. On speed controller, the power of the motor depends the width from 5% (low power/speed) to 95% (full power/speed)
Taken from http://www.josepino.com
The main disadvantage of this circuit, as all PWM circuits, is the possibility of generating radio frequency interference (RFI). It can be reduced changing the capacitor.
