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PIR to the transistor_to LEDs


Well-Known Member

Power is supplied to PIR and Arduino by a USB charge cube.
However, the whole circuit could be operated from a 12V DC power supply, if desired, by using the Arduino DC power jack.
Opto provides some spike/noise protection.
An assumption is that the central system will consist of the PIR interface(s), Arduino, and LED driver. The PIR and LED modules will be some distance away.

Last edited:


New Member
The nomenclature seems to be toggled which is incorrect. If the input received has 5.0=Motion, then the output will also be 5.0=Motion. The output is taken from emitter & not from collector. Hence the status need not change.

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