Semiconductor device, and inverter, converter and power conversion device employing the same

A semiconductor device comprising a plurality of switching circuits connected in parallel between a first node and a second node, each of the switching circuits including:

• a first switching element having a first electrode connected to the first node;
• a second switching element having a first electrode connected to a second electrode of the first switching element, and a second electrode connected to the second node;
• and
• a third switching element connected in parallel with the second switching element,
• wherein a breakdown voltage between the first electrode and the second electrode of the first switching element is higher than a breakdown voltage between the first electrode and the second electrode of each of the second switching element and the third switching element,
• wherein an on-resistance value of the second switching element is higher than an on-resistance value of the third switching element,
• wherein control electrodes of the first switching elements are connected together to a first control terminal;
• wherein control electrodes of the second switching elements are connected together to a second control terminal;
• wherein control electrodes of the third switching elements are connected together to a third control terminal;
• wherein the first switching element includes a first transistor,
• wherein the second switching element includes a first resistor and a second transistor connected in series,
• wherein the third switching element includes a third transistor, and
• wherein 1≦Gm≦1000 and 7×Gm−1.6≦r≦170×Gm−1 hold where r represents a resistance (Ω) of the first resistor and Gm is a conductance (S) of the second transistor.