HC SR501 Passive Infrared Sensor (PIR)

Links

• Datasheet

Limitation notes

• Uses 5-20V on VCC
• Arduino Pro mini in the kit has 3.3V

Stuff to first tryout before confirming

• Bypass voltage regulator in order to avoid level shifting
• datasheet for it is https://www.digchip.com/datasheets/download_datasheet.php?id=385508&part-number=HT7133
• Put 3.3V directly on Vout? Bypasses protection diode
• desolder the HT7133 and C101 (22uF cap) out and bridge Vin (middle pin) to Vout (right pin)?

Sample code

Simple test code can be found at adafruit => https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/using-a-pir