Overview

Tesla Model 3 Premium Amp reverse engineering and A2B demo for EVAL-AD2410WDZ or ADAU1452. This project may be useful for those who wish to integrate the Tesla amp into a DIY car audio project, or extract digital audio from the ICE.

Status for ADAU1452:

• Analog audio input to the DSP works via the onboard ADAU1761 codec.
• Custom filters and limiters provide rear, subwoofer, and tweeter outputs
• The class AB amp (channels 4-7) still does not play any audio. More reverse engineering will be required to fix this. Fixed
• For now, only rear, tweeter and subwoofer channels play audio. Front and center channels need work. All channels now work, but front channels are really attenuated. Swapped front and rear channels as a temporary workaround.
• Crackling on channels 2 and 3. Fixed

Status for Jetson Nano:

• The A2B bus will drop as soon as the audio interface goes to sleep. DAPM needs to be disabled since the bus needs a constant clock.
• The class AB amp (channels 4-7) still does not play any audio. More reverse engineering will be required to fix this. Fixed
• Crackling on channels 2 and 3. Fixed

Plans:

• Get all 8 audio channels playing audio. Done
• SPDIF input
• Auto source selection
• I2S input and configuration from an audio host (e.g. Jetson Nano)
• Digital volume control
• Bass, treble adjustment
• Manual EQ and presets
• Dynamic EQ
• Linux codec driver

Files:

bin:

• a2bapp-linux (When ran, this will set up the A2B bus when the Jetson nano, A2B master, and Tesla amp are connected.)
• run.sh (Sets up ALSA codecs and TDM interface, then runs a2bapp-linux)

config:

• asound.conf (Janky workaround to play stereo audio on all channels without DSP upmixing.)

datasheets:

• AD2428W A2B transceiver (Register and pin compatible with AD2410)
• TDA7802 quad amp
• TDA7803a amp (Describes registers compatible with TDA7802)
• FDA2100 amp
• PCA9538 I2C GPIO expander
• LM2901 quad comparator
• 24C04K 4 Kbit I2C EEPROM

i2c-logs:

• Annotated I2C transactions between BMP and base amp/A2B transceiver

notes:

• Channel mapping
• GPIO expander pin mapping
• I2C addresses
• External connector pinouts

pulseview-captures:

• Raw I2C2 bus captures from BMP

sigma-studio-files:

• ADAU1452 with ADI surround
• ADAU1452 with custom filters
• ADAU1452 with Tesla mic array as slave 0, and amp as slave 1 (Model 3 configuration).
• Jetson nano raw 8 channels

Amplifier pinout:

Source: Tesla Model 3 Stereo - Part 9: Summary and Lessons Learned

Amp connector part numbers:

• A2B: TE AMP Mini50 2177586-1
• Class D channels/power in: Sumitomo 6098-1714
• Class AB channels: Sumitomo 6098-5713

Block diagram:

A2B board <-> Jetson Nano wiring:

I2C/TDM test points:

Top of board:

Video of it in action