| 摘要 |
PURPOSE:To enable indication of the residue for a battery after the use of a battery-operated equipment by making the residual quantity of a battery recognizable depending on the difference in the battery voltage between the states with a load and no load. CONSTITUTION:A first peak hold circuit 4 detects and holds the lowest voltage e1 of a battery power source 1 during the period of ON operation of a switch 3. On the other hand, a second peak hold circuit 5 detects and holds the lowest battery voltage e2 during the period of OFF operation of the switch 3. Then, an arithmetic circuit 6 outputs a voltage eo proportional to the difference between the voltages e1 and e2. The voltage eo is compared with a set value es corresponding to the battery residue preset by a comparator circuit 8 and the results of the comparison are indicated on a display circuit 9. Thus, the residue of a battery can be displayed after the use of a battery-operated equipment. |
