Motion Sensor Light

Turns on a White LED for 3 minutes and turns off when a human move in front of it. Uses Passive Infra Red (PIR) motion sensor.

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Op Amp Schmitt trigger

The Op Amp comparators sometimes works well under some conditions but not always. If there is a slow wave form or some noise on it, sometimes the output switch back and forth many times. So for stable operation, Op Amp comparator can be designed as a Schmitt trigger.
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Power status LED

Two LEDs indicate the power on and off status of bread board power . So it helps to confirm whether the positive and negative rails of the bread board are getting power. Green LED lights at power on and turns off after 3 seconds. Red LED turns on at power off and turns off after 3 seconds. Let us see the circuit

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