Digital synthesizer of sine-wave oscillations and reference signals of multiple frequencies

A digital generator of phase-lock detector reference signals based on 573RF2 (2048 x 8) ROM arrays is described. The generator circuit consists of a highly stable oscillator of low-frequency sinusoidal waves (K-OS < 0.01 %) and former of square-wave signals of multiple (k less than or equal to 7) frequences. A synthesizer provides digital control of sine-wave amplitude (0 less than or equal to U-0 less than or equal to 6.4 V) and frequency (4 Hz < F < 1.2 kHz), as well as phase shift (0 less than or equal to Delta phi less than or equal to 220 degrees) with respect to reference signals.