This circuit is used to identify a persons arrival automatically. It can also be used for security purposes or mainly in places which have a Entrance gate and a Exit gate.

The circuit is connected with two Pyroelectric sensors which can be also called as PIR sensors, which senses the human movement and gives output accordingly. There are two Pyroelectric sensors enabled, one for the Entrance gate and other for the Exit gate.

When any person enters through Entrance gate, the PIR sensor PY1 senses and gives an output to Transistors VT1. The transistors goes to ON state, which inturn delivers a high state to IC 555. The IC 555 immediately delivers a pulse to VT3.If the transistor VT3 is enabled, it inturn gives a trigger pulse to the music/voice IC HFC5218.Atonce a "Hello Welcome" will be heard in the speaker. Although, any music IC can be utilized here, this IC is preferred because, it has 2 trigger inputs, and also it can store 5 voices. It can say "Hello" "Thankyou" "welcome" etc.

When a person leaves, the PY2 senses it, and gives a pulse to VT4, which inturn triggers IC 555. On receiving it, the IC 555 issue a pulse to VT8, which inturn switches VT6. This VT6, triggers the second output of HFC5218 and also turns a light LED. The IC leaves a voice message "Thankyou".

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