Bench thermometer (CB20501E)

With an ultra-low consumption, this circuit can be powered by solar cells. The circuit is from a 1991 documentation.

TTL Output Magnetic Reader (CB14249E)
This reader with TTL logic compatible output uses an LM139 comparator. The circuit was found in...
LCD power supply with contrast control (CB8852E)
This circuit was obtained from a 90’s Linear Technology documentation. The circuit provides...
Moisture Detector (CB22075E)
The basis of this circuit is an LM380 that drives a speaker that emits sound when moisture is...