Semiconductor unit, semiconductor device, battery unit, and vehicle

A semiconductor unit, comprising:

• a semiconductor device including a transistor, the transistor including a first terminal for a battery, a second terminal for an inverter circuit, and a control terminal;
• and
• a controller connected to the control terminal and configured to control on-off operations between the first terminal and the second terminal, wherein
• the controller controls a voltage between the first terminal or the second terminal of the transistor and the control terminal the of the transistor to be less than or equal to a voltage at which a current flowing to the transistor is saturated at a predetermined current,
• the transistor further includes a temperature-sensing diode,
• the transistor is provided as a semiconductor chip, and
• the temperature-sensing diode is arranged in a central portion of a front surface of the semiconductor chip of the transistor.

A semiconductor device, comprising:

• a transistor including a first terminal for a battery, a second terminal for an inverter circuit, and a control terminal;
• and
• at least one bonding wire connected between an electrode of the transistor and the first terminal, wherein
• the number of bonding wires and a diameter of the bonding wire are set so that the bonding wire breaks when a current flowing to the transistor is greater than or equal to a rated current of the transistor.