Undervoltage detector with the LM3900 (CB25172E)

The figure shows how to implement an undervoltage detector using a Norton amplifier and a zener diode as the main elements.

Voltage Sextuplicator (CB18620E)
This circuit can be used in physics experiments, in ionization and in several other applications. The...
DC DC Step-Down Converter 18V x 5 A (CB12774E)
This circuit consists of a Step-Down converter (voltage reducer) that can provide a 5 A output with...
Transformerless Intercom (CB23866E)
This circuit with three transistors was suggested in a Radio Electronics magazine from February 1963....