PIR Sensor

This passive infrared sensor detects large bodies of heat using pyroelectric crystals, an op-amp, and a fresnel lens. These are standard motion detecting sensors that are commonly seen on motion-activated lights and burglar alarms everywhere. The output of this particular model produces a double pulse when activated and then stays high for a time period set by the delay pot. The delay range is between milliseconds and about 30 seconds, depending on the setting of the potentiometer. Like all PIR sensors this one has a warm up time of about two minutes before it is really stable (dependable). So don't be too anxious to if your sensor appears flaky when you first turn on your project. We also discovered that this sensor and probably most other PIR sensors will "see" right through plastic bags and thinner acrylic sheet. Be sure to test the plastic you are using in your intended application. Applications:

• Security systems
• Heat tracking devices
• People counters
• Motion-activated toys/air-fresheners/nerf guns

Specifications:

• Operating Voltage: 3.3V-5V
• Static power loss ≤50μA
• Delay time 30 secs
• Detects objects within a ≤ 110° cone, ≤5-7 meters (16-22 feet)
• PCB size: 24x32mm

Resources:

• Specs on the board
• Wikipedia page on pyroelectricity
• LadyAda's page on PIR
• Datasheet for the PIR sensor (D203S)
• Datasheet for the chip (BISS0001)