| 摘要 |
A phase-locked loop includes an input terminal (1) for receiving a binary signal, a phase comparator (3) having a first input (2) coupled to the input terminal (1), having a second input (4), and having an output (5) coupled to an input (9) of a control-signal-controlled oscillator (10) via a control-signal generator unit (7). An output (11) of the oscillator is coupled to the second input of the phase comparator. The phase comparator derives a first pulse (P1) and a second pulse (P2) in response to a signal transition from a first value to a second value in the binary signal applied to the first input and an oscillation signal applied to the second input, the first pulse having a pulse width which is a measure of the phase difference between the binary signal and the oscillation signal, and the second pulse having a pulse width proportional to +E,fra 1/2+EE .fo, where fo is the frequency of the oscillation signal. The control-signal generator unit (7) derives a control signal from the first pulse and the second pulse and applies the control signal to the oscillator, and the control-signal generator unit derives such a control signal from the first pulse and the second pulse that the phase difference is controlled substantially toward zero.
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