| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent reduction in the signal level of transmission signals to signal lines without losing hybrid balance and to attain power saving by enabling operation to be performed at a low voltage when setting up a speech by transmitting/receiving an audio signal between a slave unit and a master unit which are connected via two wires of signal lines. <P>SOLUTION: A slave unit 1 comprising a slave unit hybrid circuit 105 and a master unit 2 comprising a master unit hybrid circuit 205 are connected via two wires of signal lines L1, L2 and when an audio signal is input from a signal line side in setting up the speech by transmitting/receiving the audio signal via the signal lines, input impedance and output impedance are dynamically changed to increase the input impedance viewed from the signal line side and to decrease the output impedance when outputting the audio signal to the signal line side. <P>COPYRIGHT: (C)2008,JPO&INPIT |
