SIGNAL TRANSMISSION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a technique that improves ringing restriction effect obtained by setting a transmission line to a low impedance.SOLUTION: An impedance adjustment circuit (5) creates a low impedance state in which resistance is connected between a pair of signal lines and a normal state in which resistance is cut off. If a change in a signal level on a transmission line is detected, a first control circuit (3) controls an impedance adjustment circuit so that the low impedance state is created only for a certain period set shorter than a one-bit width. When detecting arbitration win from the comparison of transmission data with reception data, a second control unit (4) adjusts the impedance adjustment circuit according to transmission data so that the low impedance state is created for the whole period when the signal level on the transmission line is recessive until the transmission of a communication frame obtaining arbitration win is finished.SELECTED DRAWING: Figure 1