| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to suppress heat generation in the multiplexer transmission of power, sound and data, to simplify a demodulation circuit heat and to attain multiplex transmission of the data without the use of an oscillation circuit and a filter circuit. SOLUTION: A timing control circuit M13 generates drive signals SM15-18 depending on a level H or L of a data signal converted into a pulse width modulation(PWM) signal SM13 in a multiplex transmission signal transmitter side and sends a multiplex signal SG12 whose polarity is respectively +-+- and -+-+ to cable lines LN11, LN12. A polarity discrimination circuit S11 at a multiplex transmission signal receiver side generates a polarity discrimination signal SS13 of an H level when the polarity of the multiplex signal is positive and of an L level when the polarity of the multiplex signal is negative so as to convert the multiplex signal in a monopolar PWM signal SS11. |
