Thursday, March 28, 2019

Digital Audio Signal Generator

This handy instrument is a version of the design published in the Australian Silicon Chip magazine (a subscription is required to view the details of the article).

It is based on a dsPIC33 microcontroller, has TOSLINK and S/PDIF digital outputs (44.1k, 48k and 96k sample rates) and a stereo analog output. Output frequency, phase, attenuation, and other parameters are set by the keyboard. It produces sine, square, triangle, and sawtooth waves and has a variety of modes. It can be powered by an external DC source or a battery. The article claims low distortion for sinewave (less than 0.06%) and even lower with a good external DAC, but I did not verify that.

Highly recommended.