| 摘要 |
PROBLEM TO BE SOLVED: To remove high-frequency noise in a one-chip three-phase inverter that is integrated into a monolithic IC with peripheral circuits. SOLUTION: This one-chip three-phase inverter 1 integrated into a monolithic IC comprises a circuit 1a and an insulating layer 1b of a polysilicon derivative. This insulating layer 1b is jointed to the heat sink 6 of the monolithic IC. Also, the circuit 1a is connected by an aluminum wire 9 to a lead terminal 10 that becomes a circuit ground and thereby makes the grounding wire of the circuit 1a grounded. The heat sink 6 is electrically connected by a lead 7 to the lead terminal 10, so that the insulating layer 1b functions as a capacitor. Via this capacitor, the circuit 1a is connected to the heat sink 6 and then to the lead terminal 10, in terms of high frequency. Thus, high-frequency noise that occurs in the circuit 1a flows into the circuit ground via the insulating layer 1b and the heat sink 6. |
