Charge and discharge testing device

A charge and discharge testing device which performs a charge and discharge test on a secondary battery, comprising:

• first and second output terminals which connect both ends of the secondary battery;
• a bridge circuit in which first and second switch elements connected to each other in tandem through a first connection point, and third and fourth switch elements connected to each other in tandem through a second connection point are connected in parallel between a power supply line and a ground line;
• a charge and discharge current path including a shunt resistor and a first inductor, and reaching from the first connection point to the second connection point via the first output terminal and the second output terminal;
• a capacitor connected between the first and second output terminals;
• and
• a control unit which receives a mode signal to designate a first or second mode, and controls the first to fourth switch elements based on the mode signal,
• wherein when the mode signal indicates the first mode, the control unit controls the first to fourth switch elements so that the first and the fourth switch elements and the second and the third switch elements are alternately turned on and off, and
• wherein when the mode signal indicates the second mode, the control unit controls the third switch element to be an off state and the fourth switch element to be an on state, and apples control to continuously change an analog voltage greater than or equal to a gate threshold voltage up and down to the first switch element at a time of charge control and to the second switch element at a time of discharge control.