摘要 |
<p>A circuit configuration for a direct-voltage power pack of an electronically controlled switching device, particularly of a small programmable control system, which is externally supplied with voltage, having an arithmetic-logic unit, signal inputs and signal outputs. This circuit has a back-up supplier for the backup supply of the supply voltage and a detector for detecting the input voltage which is not backed up, the detector interacting with the arithmetic-logic unit in such a way that, in response to any voltage failure, the signal inputs are reliably prevented from being read in.</p> |