| 摘要 |
<p>PURPOSE:To provide a transmitter which can be stably provided with a clock signal to be a reference through a transmission line. CONSTITUTION:A clock extraction part 18 prepares an extracting clock signal 19 based on a transmission line signal 13. This signal 19 and a reference clock signal 11 are supplied to a switching part 15 and besides, the presence/absence of abnormality is monitored by respective abnormality detection parts 16 and 21. This monitored result is inputted to a switching control part 24, and the switching part 15 is controlled. When the first abnormality detection part 16 detects no abnormality, the reference clock signal 11 is outputted from the switching part 15 and supplied to a phase locked oscillation part 28, and the various kinds of clock signals 291-29N to be used inside the device are prepared. When the second abnormality detection part 21 detects no abnormality although the reference clock signal 11 gets abnormal, the extracting clock signal 19 is outputted from the switching part 15.</p> |
