lights led circuits schematics


Posted on Feb 5, 2014

The circuit uses two LDRs which are placed one after another (separated by a distance of say half a metre) so that they may separately sense a person going into the room or coming out of the room. Outputs of the two LDR sensors, after processing, are used in conjunction with a bicolour LED in such a fashion that when a person gets into the room it


lights led circuits schematics
Click here to download the full size of the above Circuit.

emits green light and when a person goes out of the room it emits red light, and vice versa. These outputs are simultaneously applied to two counters. One of the counters will count as +1, +2, +3 etc when persons are getting into the room and the other will count as -1, -2, -3 etc when persons are getting out of the room. These counters make use of Johnson decade counter CD4017 ICs. The next stage comprises two logic ICs which can combine the outputs of the two counters and determine if there is any person still left in the room or not. Since in the circuit LDRs have been used, care should be taken to protect them from ambient light. If desired, one may use readily available IR sensor modules to replace the LDRs.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

12Vdc Mobile Battery Charger
A Simple Metal Detector Circuit Using Beat Frequency Oscillator (BFO)
High-voltage power pulse circuit
mp3 mode circuit wtv020sd 16p tutoria
The Forward Converter
ELECTRONIC STUDIO - RF AMPLIFIERS LINEAR AMPLIFIER FM AMPLIFIER
3-channel Audio Amplifier circuit



Top