摘要 |
A simplified analog passive infrared motion detection circuit operates using only four operational amplifiers. A first amplifier is used as part of a bandpass amplifier circuit, a second is used in an inverter circuit, a third is used in an integrator circuit and a fourth is used in a threshold comparator circuit for generating an alarm output signal. The circuit is built using a single quad op amp IC package and is economical to manufacture. The third op amp can alternatively be used as a passive infrared sensor preamplifier and a transistor can be used in the integrator circuit, so that a regulated power supply for the circuit is not needed.
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