| 摘要 |
PROBLEM TO BE SOLVED: To effectively shorten turn-off time of a switch element of a charge and discharge switch circuit, and to suppress flyback voltage within a range which is not beyond withstand voltage of the switch element. ! SOLUTION: A charge and discharge switch circuit comprises: a switch element 3 connected in series to a charge and discharge line 2 from a secondary battery 1; a drive power supply 4 which generates drive voltage for conducting the switch element; a switching control resistor 6 one end of which is connected with a control terminal of the switch element; a shortening circuit which consists of a series circuit between a Zener diode 7 and a current limit resistor 8, and is connected in parallel with the switching control resistor by arranging a cathode of the Zener diode to a switch element side; and a switch control part 5 which controls voltage supply to the control terminal of the switch element. The switch control part applies the drive voltage to the other end of the switching |
