| 摘要 |
PURPOSE: To improve the safety of a charging type power unit by detecting the coming off of the terminal of a charge/discharge control circuit. CONSTITUTION: A charge/discharge control circuit controls a secondary battery composed of two or more batteries connected in series. Voltage dividing circuits 113 and 114 are respectively connected to the batteries and voltage detecting circuits 115 and 116 respectively detect the divided voltages of the circuits 113 and 114. When the batteries over-discharge or are over-charged, the voltages detected by means of the detecting circuits 115 and 116 vary. Signals indicating the variation of the voltages are inputted to a control circuit 117 and the circuit 117 outputs a signal VS to a switch circuit incorporated in a power unit so as to stop the over-discharging or over-charging. A constant-current circuit 118 is provided to detect the disconnection of the connecting point between the connecting point of the batteries and the charge/discharge control circuit. |
