| 摘要 |
PURPOSE:To hold the contents of storage of a CMOS semiconductor storage element for a considerably longer timer even after the alarm of battery voltage drop, by connecting lithium batteries in parallel and providing a difference in power consumptions between the lithium batteries. CONSTITUTION:A power supply terminal 1 is connected to a CMOS semiconductor storage element 7 via a diode 3 and a lithium battery 2a is connected to the CMOS semiconductor storage element 7 via a diode 4. A lithium battery 2b is connected to the element 7 via diodes 8a and 8b in series connection and the battery 2a is connected to a detection circuit 6 which detects the voltage of battery via a diode 5. Thus, even if an electromotive force of the battery 2a is made smaller and alarm is given to the voltage detection circuit 6, since the battery 2b has a sufficient capacity, the contents of storage can be held until the next periodical inspection. |
