This simple three-LED sensor uses an NTC at the input. The circuit is based on an uncommon integrated component today. We found it in documentation from the 80s.
With a touch of the push button the lamp is switched on. A new touch and the lamp go out, in this...
This circuit was obtained from Maxim documentation. The circuit has 4.5 and 5.5V thresholds for...
This circuit has a configuration very explored in our projects. The range can exceed 200 meters and...