A compact USB audio interface built around the Texas Instruments PCM2706, with two channels of analog audio and I2S out. The device supports up to 16-bit 48 kHz audio. Additional details can be found on the hackaday.io project page.
The schematic is based heavily off of the PCM2706 reference design. While the schematic does have the HID buttons designed in, the final board does not implement them.
The PCB is a two layer board that measures 1 inch by 1 inch. It can be ordered via OSH Park using the link below.
Front
Back
https://oshpark.com/shared_projects/LmhMixU9
The passive components are mainly 0603, with a few aluminum caps, the crystal, the main IC, and the USB connector. An online BOM can be found on Octopart via the link below.
| Designator | Value | Size |
|---|---|---|
| U1 | PCM2706 | TQFP32 |
| Y1 | 12 MHz | 3.2mm x 2.5mm |
| P1 | USB Micro B | |
| C1, C2 | 18 pF C0G | 0603 |
| C3, C4, C5, C7, C8 | 1 uF X7R | 0603 |
| C6 | 10 uF | 4 mm |
| C9, C10 | 100 uF | 5 mm |
| C11, C12 | 0.022 uF X7R | 0603 |
| R1 | 1M | 0603 |
| R2, R11 | 1K5 | 0603 |
| R3, R4 | 22R | 0603 |
| R5, R6 | 16R | 0603 |
| R7, R8, R9, R10 | 3K3 | 0603 |
https://octopart.com/bom-lookup/FlH2LCsP
This project is licesned under the CERN Open Hardware License 1.2.