| 摘要 |
PURPOSE:To accurately detect a battery voltage by instantaneously holding a battery at its original potential corresponding to its charging state at the time of battery voltage detection even when a nickel cadmium battery, etc., is used as the backup battery. CONSTITUTION:When the secondary battery 11 is charged, a switching transistor(TR) 13 is turned OFF and a switch TR 15 is turned OFF to supply the charging current from a constant current circuit 12 to the secondary battery 11. Once the detection of the battery voltage is indicated, the switch TR 13 is turned OFF and the switch TR 15 is turned ON, so the charging circuit is disconnected from the secondary battery 11 and a load circuit 14 for voltage adjustment is connected to the secondary battery 11. In this state a voltage detector 17 detects the battery voltage. |
