Direct digital synthesiser with quasi continuous temperature compensation
Marian A. Taslakov · 2002
In this work we suggest a new method for obtaining quasi-continuous temperature compensation of a direct digital synthesiser (DDS). The suggested method uses an entirely digital temperature compensation of the DDS output frequency. We obtained a temperature stability better than 0.2 ppm in the temperature range from -45 to +85/spl deg/C for the extremely wide frequency range from 10 Hz to 140 MHz. Additional advantage of the method is that we do not use a voltage controlled crystal oscillator (XO) which improves the DDS output spectrum and eliminate a circuit source of ageing, hysteresis, and noise.