Optical schmitt trigger

Posted on Sep 2, 2012 6916

Under:: Light Sensing Circuits / Light Laser LED Circuits

This circuit shows a 555 with its trigger and threshold inputs connected together used to energize a relay when the light level on a photoconductive cell falls below a preset value

Circuit can be used in other applications where a high input impedance and low output impedance are required with the minimum component count.

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