Power semiconductor device, power conversion device, and electric system

A power semiconductor device comprising a first upper-arm circuit body configured by sandwiching a first switching element constituting an upper-arm circuit between a first conductor and a second conductor, and a first lower-arm circuit body configured by sandwiching a second switching element constituting a lower-arm circuit between a third conductor and a fourth conductor, the power semiconductor device comprising:

• a substrate in which a positive electrode wiring connected to the first conductor on a high potential side and a negative electrode wiring connected to the fourth conductor on a low potential side are provided on one surface, and an output wiring connected to the second conductor and the third conductor is provided on an other surface so as to face the positive electrode wiring and the negative electrode wiring;
• and
• a first capacitor that smooths DC power supplied to the first upper-arm circuit body and the first lower-arm circuit body, wherein
• the substrate is disposed between the first upper-arm circuit body and the first lower-arm circuit body, and
• the first capacitor is disposed between the first upper-arm circuit body and the first lower-arm circuit body, and is connected to the positive electrode wiring and the negative electrode wiring on the substrate.