| 摘要 |
The invention concerns a function taking place in a digital phase lock, when it is desired to exchange a synchronization signal supplied to the phase lock for another synchronization signal. Using a cut-off circuit, the phase difference between a selected reference signal and a signal formed by dividing from an oscillator signal is set with time constant accuracy at the setting value for the phase difference. The method according to the invention, then uses as phase setting value the current value of the phase difference obtained by cut-off connection. Thus, the method according to the invention begins using a reference signal-specific setting value instead of a fixed setting value. Since the setting value is determined adaptively in accordance with the signal of the synchronization source used at each time, no phase transfer will occur during the change. |
