Phase-controlled high frequency oscillator

摘要

A phase-controlled high frequency oscillator has a phase comparator for comparing the oscillator frequency to a reference frequency which comparator controls two direct current sources connected to a charging capacitor for supplying charge pulses to the charging capacitor which in turn generates a charge voltage which determines the frequency of the oscillator, which is voltage controlled. The control of the current sources is undertaken in such a manner that in the steady-state condition of the phase control loop, both current sources supply relatively short charge pulses of equal size and opposite polarity to the charging capacitor. An auxiliary circuit generates a correction current proportional to the integral of the difference between the charge pulses supplied by the two current sources and is connected to the charging capacitor for further controlling the voltage controlled oscillator. The auxiliary circuit is designed such that only relatively short charge pulses generate a correction current.