PHASE LOCKED LOOP

摘要

The invention relates to a phase locked loop comprising a voltage-controlled oscillator (1) having two tuning inputs (11, 12). A feedback signal (VTUNE) can be supplied to a tuning input (11) in a conventional phase locked loop by means of a frequency divider (2). Furthermore, a frequency word used to adjust the divider ratio of the PLL, and thus used for frequency pre-selection, is not only supplied to the frequency divider (2), but is also used for the compensatory tuning of frequency-defining components (14) in the oscillator (1). The inventive phase locked loop enables the frequency drift to be significantly reduced - especially in cost-effective open loop modulation methods - by means of a low or disappearing deviation of the tuning voltage (VTUNE) in connection with a reduction of the memory effect of capacitors in loop filters (6), with especially simple measures in terms of circuit technology.