| 摘要 |
<p>PURPOSE:To execute the control of equipment to meet the life of a battery by determining whether the further usual operation of the equipment is to be executed or not by using a dummy circuit having the same voltage drop as a prescribed peripheral circuit necessitated for the normal operation of the equipment. CONSTITUTION:When a signal is outputted from an output port 51 in order to detect the voltage of the battery B, a transistor(TR) Tr2 is turned on, the the TR Tr1 is turned off, and the output level of the output port 51 becomes Vss. Afterwards, prescribed dummy arithmetic operation is executed, and it is investigated whether the signal could be detected from an input port 52 or not. In the case of the detection of the signal, the TR Tr3 of the input port 52 is turned on, and in the case of the non-detection of the signal, the TR Tr4 is turned on. In this case, it is decided that supply voltage fell to the voltage not enough for operating the circuit normally, and since a flay for the informing processing of the lowering of the voltage and preventing key input is turned on, processing based not the further key input is inhibited. Thus, the electromo tive force of the battery B can be surely used to the very limit of its life.</p> |
