| 摘要 |
PURPOSE:To operate an oscillation circuit and a frequency division circuit of a real time clock with low power consumption keeping the stable functioning by switching the operating voltage and performing the switching control in the real time clock. CONSTITUTION:A constant voltage circuit of a real time clock capable of switching between at least two voltages by the variation of switch signal is constituted to be controlled by a switch signal generator. The switch signal generator is constituted so that it monitors external signals, activates the switch signal if no signal variation occurs for a specified time, terminates the counting and does not activate switch signal if any signal variation occurs within the specified time. |
