| 摘要 |
PURPOSE:To display a battery voltage without flicker due to noise by a method wherein a voltage obtained from a battery meter of an apparatus using a battery is displayed through the intermediary of a high-cut filter. CONSTITUTION:A voltage obtained from an operational amplifier 471 of a battery meter circuit 47 and being in the range larger than a voltage of a battery 41 whereat an apparatus using the battery is operable is enlarged by an operational amplifier 472 forming a level shifter and supplied to a diaplay circuit. A capacitor C5 and a resistor R9 arranged in parallel and forming a high- cut filter are in feedback connection with said amplifier 472. A high frequency component based on a noise supplied to the display circuit is thereby removed, and thus a battery voltage in a necessary range is displayed in such a manner that it is easy to see without flicker. |
