This circuit is from the Motorola Linear Databook of 1990 and can be implemented with other operational amplifiers. The power supply must be symmetrical.
Small time intervals up o some minutes can be achieved with this circuit. Only incandescent lamps...
This circuit triggers an alarm when the mains power is cut off. The circuit was found in the July...
This circuit has more sensitivity than the previous one (CB4114E) for using a full-wave detector...