Close
0%
0%

New 8x8 and 16x16 TDM Audio Board for Teensy

A stackable, multi-channel audio board for Teensy 4.x.

Similar projects worth following
The CS42448 CODEC chip used in Paul Stoffregen's original multi-channel audio board for Teensy has gone EOL, necessitating a new approach.

The TLV320AIC3104 stereo CODEC is a good match, as it can be programmed to use different TDM slots, has on-board analogue filters and PGAs on the inputs for microphones. Inputs and outputs are balanced or single-ended, and the outputs can drive headphones or balanced lines.

The boards each host four stereo CODECs (8 inputs and 8 outputs) and can be stacked to provide 16 inputs and 16 outputs.

Every channel of each CODEC can be programmed individually, providing lots of flexibility, particularly when teamed up with the extensive range of widgets in the Teensy Audio Library.

A Teensy Audio compatible control library is provided with a modified TDM driver that fixes an issue in the standard TDM driver which doesn't transfer odd channel data correctly.

The CODECs

  • Can support microphone to line-level inputs in balanced or unbalanced mode.
  • Outputs can drive 600 ohm balanced lines or headphones.
  • Have inbuilt analogue filters on the inputs and outputs reducing parts count.

The main PCB has eight balanced inputs and outputs leading to IDC headers carrying four channels each, allowing audio connector options to suit individual project requirements.

As the TLV320AIC3104 CODECs are QFN (no pins) packages, PCB Assembly is strongly suggested. The main board files provide everything necessary for JLCPCB's PCBA service.

Several 4-channel Wing boards provide input and output connections.  

  • Outputs: Balanced XLR and TRS (1/4"). Stereo headphone (1/8") 
  • Inputs: XLR, XLR Combo, TRS and  XLR inputs with Phantom power.

The hardware repository is at https://github.com/palmerr23/Teensy8x8AudioBoard

The Teensy audio driver is at https://github.com/palmerr23/control_TLV320AIC3104

Boards are available on Tindie https://www.tindie.com/products/37676/

Input Output XLR Wing Board.png

The XLR board can be configured as input or output. For correct signal polarity, male (output) sockets are mounted on the underside of the board.

Portable Network Graphics (PNG) - 212.88 kB - 03/15/2025 at 03:20

Preview

XLR Input Output Wing Board Schematic.pdf

Adobe Portable Document Format - 20.64 kB - 03/15/2025 at 03:20

Preview

Wing Board 4 TRS Mk III.png

The TRS wing board for inputs or outputs. The 1/8" headphone jacks are only valid for output connections.

Portable Network Graphics (PNG) - 339.79 kB - 03/15/2025 at 03:19

Preview

TRS Wing Board Schematic.pdf

Adobe Portable Document Format - 28.07 kB - 03/15/2025 at 03:19

Preview

tlv320aic3104 audio rev K twist.png

The main PCB. Most connectors have been omitted for clarity.

Portable Network Graphics (PNG) - 317.18 kB - 03/15/2025 at 03:18

Preview

View all 6 files

  • 4 × TLV320AIC3104 Stereo TDM compatible CODEC
  • 1 × PCA9546 Logic ICs / Decoders, Encoders, Multiplexers, DemultiplexersI

View all 6 project logs

Enjoy this project?

Share

Discussions

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates