research & experiments for outputting analog audio using digital IO pins.
Most notably, this repository contains an amaranth-lang fixed-point library and an implementation of a delta-sigma noiseshaper that can be used to output analog audio from FPGAs or ASICs.
The noiseshaper will (hopefully) be taped out as part of the FPGA-Ignite Summer School hackathon ASIC. For the details of the physical implementation, see the openlane folder.
Originally, this repository contained ideas and research for building a fully digital class D amplifier using an FPGA (thus the name), however that effort stalled a bit. If you are interested in pursuing this further, feel free to contact me :).