The Parallax Inc sensor is a pyroelectric device that detects motion by measuring changes in the infrared (heat) levels emitted by surrounding objects. This motion can be detected by checking for a sudden change in the surrounding IR pattern. When motion is detected, the PIR sensor outputs a high signal on its output pin. This logic signal can be read by a microcontroller or used to drive an external load.
Note
The product information found on this page currently pertains to Revision B of this product, which provides many updates and new features from Revision A.
Parallax offers an extensive range of sensor, communication and interface modules for the experimental working on robotic systems. Most of them are supplied with extensive documentation making them ideal for use in education.

Detects a person up to 10m away, or up to 5m in reduced sensitivity mode
Jumper selects normal operation or reduced sensitivity
Supply current up to 12mA at 3V, 23mA at 5V
On-board LEDs light up the lens for fast visual feedback when movement is detected
Mounting holes for 2-56 sized screws
3-pin SIP header ready for breadboard or through-hole projects
Small size makes it easy to conceal
Easy interface to any microcontroller
Power requirement: +3 to +6VDC, 130μA idle, 23mA active (no load)
Communication: Single-bit high/low output
Dimensions: 35.8 x 25.4 x 20.3mm
Operating temperature ranges between 0°C and 50°C
Approximately 90° field of view

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