| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a termination detection circuit that can accurately perform termination detection without adding a complicated circuit. <P>SOLUTION: A termination detection circuit 100 is constituted by a low-pass filter 1, a D/A converter 2, a comparator 3, a vertical flyback period detector 4, an oscillator 5, an OR circuit 6, and a timer 7. A video-signal output terminal of an output circuit 30 is connected to a connector 31. A video input terminal of a receiver circuit 40 is connected to a connector 41. The connector 41 with a cable is connected to the connector 31, and then a video signal from the output circuit 30 is transmitted to the receiver circuit 40. A transmission end is terminated by a termination resistor R. The termination detection circuit 100 determines that the transmission end is terminated when a pedestal level of the video signal in the vertical flyback period is smaller than a threshold level of an output of the D/A converter 2 by the comparison result from the comparator 3. <P>COPYRIGHT: (C)2013,JPO&INPIT |
