| 摘要 |
<p>A switching circuit 33 comprises a connection circuit cascade-connecting control terminals for controlling switching of n number of transistors M1-Mn via n-1 number of coils L1 respectively (n is an integer equal to or more than 2; and coils L3 respectively connected between one end of each of the transistors M1-Mn and other end of a coil L2, one end of the coil L2 being electrically connected to a DC power source. The transistors M1-Mn is sequentially switched with PWM signals inputted to an input terminal of the connection circuit. The switching circuit 33 further comprises a transistor M0 inserted at the one end or the other end of the coil L2 in cascade-connection.</p> |
