16-05-2010, 09:17 AM
When the intensity of sound exceeds certain intensity, the alarm is
triggered and the siren begins to operate. The speaker beeps and the flasher
(light) flashes. Thus the owner of the residence is alerted when an intruder comes.
The functional block diagram includes
-MICROPHONE
-AMPLIFIER
-LATCH
-OSCILLATOR
-FLASHER
-SPEAKER
a 600O unidirectional moving coil microphone is used. LM386 CMOS operational amplifier was the main component in the amplifier. It had a gain of 200. The amplifier then passes it on to the latch section of the burglar alarm circuit for further processing. The CD4013B dual D-type flip-flop is a
monolithic complementary MOS (CMOS) integrated circuit. It has the inputs D, Q,QBAR The logic level present at the ?D? input is transferred to the output during the positive-going transition of the clock pulse. Setting or resetting is independent of the clock. Once a sound that exceeds certain intensity, it is picked by the microphone, amplified
and sent to the latch, the latch keeps the alarm still ringing until the reset button is pressed.
Circuit diagram ,components and further details in this pdf:
ljs.academicdirectA09/097_102.pdf
