| 摘要 |
The data saving circuit prevents loss of stored data upon an interruption in the network voltage for the telephone answering machine, using a capacitor (C) with an extremely high capacitance, connected in parallel with the supply voltage (NT). The capacitor is connected via a switching transistor (T) to a digital signal processor (DSP), controlling a self-refreshing mode for the read/write memory (DRAM), via a multiplexer (MUX), supplied with a 32 kHz signal from the central microcomputer of the telephone peripheral. Pref. the self-refreshing mode is activated by a pulse generated in dependence on the 32 hKz signal upon loss of the supply voltage. |
