Human Body Pyroelectric Infrared Induction Alarm Circuit Kit Welding Electronic Training DIY

Feature Board size 5 4 9cmPower supply voltage 5 6V DCFunction realization The human body infrared sensor alarm circuit is composed of pyroelectric infrared sensor PIR1 D203S infrared sensor signal processor U1 BISS0001 voice chip IC1 C002 and alarm circuit The circuit can be used as a home anti theft without sound light vibration even in a dark state once it enters the monitoring range the circuit will automatically detect and emit a high intensity alarm Circuit principle 1 BISS0001 is a digital analog dedicated integrated circuit composed of an operational amplifier a voltage comparator a state controller a delay time timer and a blocking time timer 2 Add a DC voltage of 5 to 6V to J1 in the circuit When the pyroelectric infrared sensor PIR1 detects the infrared signal radiated by the human body in front the S pole of PIR1 outputs a weak electrical signal which is sent to U1 14 pin by The internal operational amplifier OP1 performs stage amplification and then outputs from pin 16 which is coupled to pin 13 via C9 to perform the second stage amplification for the operational amplifier OP2 Then it is detected by the bidirectional amplitude discriminator composed of the voltage comparators COP1 and COP2 and then detected The effective trigger signal VS starts the delay time timer After the output signal VO at pin 2 is divided by R14 and R15 it is supplied to the power supply voltage at pin 4 of IC1 The second pin of IC1 outputs 110 alarm music