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Fully Pipelined DDS Synthesizer or NCO



Fully Pipelined DDS Synthesizer or NCO

Details

Category: DSP Core

Created: Dec 22, 2008

Updated: Jan 27, 2020

Language: VHDL

Other project properties

Development Status: Stable

Additional info: Design done, FPGA proven

WishBone compliant: No

WishBone version: n/a

License: LGPL

Description

The DDS IP core (dds_synthesizer) is a implementation of a direct digital frequency synthesizer (DDS) (also called number controlled oscillator, NCO) which produces a sinewave at the output with a specified frequency and phase (adjustable at runtime). Only one quater of the sinewave is stored in the LUT, the rest is computed by simple operations (negating, subtraction), resulting in a reduced memory requirement. The resolution of the frequency tuning word (FTW), the phase and the amplitude defined seperately. Several precomputed look-up tables are provided as combinations from 8 to 16 bit phase and amplitude resolution. The frequency resolution can is defined as generic. A matlab script for generating the LUTs for different resolutions is included. The design is fully pipelined for maximum throughput.

DDS Implementation

If you find something interesting, feel free to contact me: pluto[at]ls68.de