| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a signal transfer circuit that can be prevented from malfunctioning even when a coupling coefficient of a transformer is low. <P>SOLUTION: The signal transfer circuit comprises: a drive circuit 5 for applying a voltage with a positive polarity to a primary side coil of a transformer 193 with start timing of an input signal and causing the primary side coil to generate voltage with negative polarity with fall timing; a secondary side circuit 192 for causing an output signal to rise when a voltage with positive polarity is generated in the secondary side coil and for causing the output signal to fall when a voltage with negative polarity is generated in the secondary side coil of the transformer; and a resistor 8 for applying to the primary side coil of the transformer a voltage with negative polarity with a level by which the secondary side circuit 192 does not operate after a voltage with positive polarity is generated in the primary side coil, and for causing the primary side coil to generate a voltage with positive polarity with a level by which the secondary side circuit 192 does not operate after the voltage with the negative polarity is applied to the primary side coil. <P>COPYRIGHT: (C)2009,JPO&INPIT |
