PIR Light Switch(or Any AC Device) Without Microcontroller
by XavierJ4 in Circuits > Electronics
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PIR Light Switch(or Any AC Device) Without Microcontroller

This is a simple circuit for activating a relay connected to an AC (or DC for that matter) Device like a bulb,
I am going to assume you know how to use a relay and basic electrical wiring (google is your friend)
The circuit is designed for the use with 12v DC supply but can be easily converted into 5v supply design by using a 5v relay and shorting out the Vin and Vout of the voltage regulator(7805), make sure to test out the design in a breadboard before moving on to more permanent set up like a PCB
Materials Required
Testing
1.Breadboard
2.wires
3.Multimeter
4.Led
Final Assembly
PCB Clad/Perforated Board(This tutorial will be based on the PCB )
12v/5v Relay
Resistors (I used 1k,But make sure to keep a few standard values )
BC547 transistor
7805 voltage regulator(when using 12v supply)
Diode
Screw terminals,2 point,3 point
Female Header
PIR Sensor(Obviously)
Schamatic


I have attached images of the schematic and the link to the schematic and PCB board file (EAGLE )
https://github.com/Xavier-John/Pir-Switch
Test the circuit on a breadboard with 5v dc instead of 12v with an led Instead of the relay once everything is ready
PCB Etching and Soldering

U can Etch the PCB using the toner transfer method (u should check out other Instructables or google it for more info) and then solder it to the pcb and test it with 5v supply or 12 v supply (make sure to include a 7805v regulator)
Testing and Calibration
Look up this link on calibrating the PIR sensor
https://learn.adafruit.com/pir-passive-infrared-pr...
After soldering and assembly get a light bulb and holder and move around in front of the sensor and see if it lights up, some calibration may be required on sensitivity and delay
And thats it
Make sure to mention any errors or improvements in the comments..
Thank you