Protection circuit for control circuit - prevents computer from executing incorrect function when power supply fails

摘要

The protection circuit has a switch (S) connecting the load (V) to a battery (B) and a second switch (ES) co connecting a control circuit (ST) to the same battery. A capacitor (C) is connected to the inout side of the control circuit. The second switch is an electronic switch and keeps the control circuit and capacitor disconnected from the battery for a given time after the first switch has closed. The second switch may be an FET driven by a monoflop coupled via an input amplifier to one pole of the battery. Alternatively, a flip-floo may be connected between the monoflop and the FET gate and be controlled by a comparator comparing the battery voltage with a reference.