| 摘要 |
An apparatus and a method of synchronizing clock during line connection in switching system are provided to automatically switchover the clock coming in the digital office line to the master clock by setting up the other digital office line interface board as a master in the digital office line connection. An interface unit(11) outputs a reference clock. A controller or a buffer(13) outputs a selection signal according to the connection control signal. A selecting unit controls the output of the reference clock according to the selection signal. A phase locked loop circuit(31) and a voltage controlled oscillator(32) output the clock synchronized in the reference clock. A TDM switch and a clock generator(33) produces a sync clock and provides to each digital office line interface board. A controller(34) generates a connection control signal. |
