Title :
A direct digital synthesizer with interpolation circuits
Author :
Nakagawa, Tadao ; Nosaka, Hideyuki
Author_Institution :
NTT Wireless Syst. Labs., Kanagawa, Japan
fDate :
5/1/1997 12:00:00 AM
Abstract :
This paper presents a direct digital synthesizer (DDS) with no ROM that still produces square waves with low spurious signals. The main features are the interpolation of the analog-converted accumulator contents and the extraction of timing at the points where the interpolated signal is identical to a continuous sawtooth waveform. Experimental results confirm successful frequency synthesizer operation. The output frequency is determined by the frequency control word, and spurious signals present in the accumulator contents are greatly reduced
Keywords :
CMOS integrated circuits; direct digital synthesis; elemental semiconductors; frequency control; interpolation; mixed analogue-digital integrated circuits; silicon; square-wave generators; timing; DDS; Si; analog-converted accumulator; direct digital synthesizer; frequency control word; frequency synthesizer; interpolation circuits; low spurious signals; square wave output; timing extraction; Circuits; Clocks; Degradation; Frequency control; Frequency synthesizers; Interpolation; Phase locked loops; Read only memory; Timing; Tuning;
Journal_Title :
Solid-State Circuits, IEEE Journal of
