This circuit indicates when the voltage of a 12 V battery is low. With changes, for example, the zener, the circuit can be used to monitor other voltages.
This circuit was obtained in a 1980 publication. The transistors can be BC548 or 2N2222. The...
We found this circuit in an old documentation. Its purpose is to turn on warning lights when the...
This circuit uses the Linear Technology LT6505 and was found in a 2005 manual. The circuit is for 24 V...