Position: Index > Lamp Circuit >

DC_LAMP_DIMMER

2016-08-04 23:21  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.


DC_LAMP_DIMMER
The dc lamp dimmer circuit will adjust the brightness of a dc lamp or the speed of a suitable dc motor. An oscillator is formed around Schmitt inverter IC1a, and is buffered by IC1b. This, in turn, drives TR1, which is a Darlington power transistor. The lamp LP1 forms the collector (c) load for the transistor, and this is driven at a nominal 330 Hz. The duty cycle is, however, fully variable using potentiometer VR1. Consequently, the power delivered to the load can be controlled between 5 and 95 percent, approximately. No flicker will be apparent at this frequency. The circuit consumes little power itself and is ideal for controlling car instrument panel lights.