Oscillation-Frequency Stabilization Using Negative Feedback Control in Self-Excited Current-Feedback Magnetic Multivibrator.

Though current-feedback magnetic multivibrators are highly efficient and reliable, the oscillation frequency normally varies according to the load current. This paper proposes a new, negative-feedback-controlled, current-feedback magnetic multivibrator. The resulting circuits have almost constant oscillation frequency, provided by a control circuit including a frequency-voltage converter (F-V converter). Two types of F-V converter were used. One is a monostable multivibrator, and the other is a phase-locked loop (PLL). New magnetic multivibrators using the frequency compensation circuit thoroughly cancel the dependence of junction voltages on the load current. Variations in saturated flux of the saturable core also have no effect on the oscillation frequency. Oscillation frequency was best compensated at a fixed value when a PLL was employed.