[Azure Archives] Jerry DSP Bluetooth TWS Color Silkscreen Module

Considering the copyright issues associated with color silkscreen printing, as well as the potential for resale and commercial use, I will no longer provide complete designs. I will only provide copyright-free backgrounds or complete designs with watermarks. If you require color silkscreen printing, you will need to find the images yourself, assemble them, and then place them on the PCB. Alternatively, you can obtain authorization from the relevant copyright holders or companies, submit screenshots of the authorization to me, and I can provide the original source files.
 
1. Introduction:
This Bluetooth module, using the JL AC7916A chip for analog audio input, features DSP, Bluetooth, and TWS functions. It's a small, color-screened PCB

with a built-in DSP that supports online EQ adjustment (default 10 bands, can be increased to 30 bands with a configuration file, but this consumes more FLASH).
The built-in DSP supports DRC (LowBand DRC, HighBand DRC, full-band DRC to be added later). It supports
Bluetooth playback (BLE V5.3, supports SBC)
, TWS interconnection
, AUX sampling: 48kHz sampling rate (2 channels )
, AUX playback: 48kHz ,
UAC playback (USB sound card)
, USB playback (supports AAC, ADPCM, AMR, APE, DTS, FLAC, M4A, MP1, MP2, MP3, OPUS, SPX, WAV, WMA, PCM audio decoding formats), and
TF card playback (single-line).

 
There are actually many similar chips, such as the Mountainview BP1048, but they are not open-source.
This project is based on
 the JL AC7916A Bluetooth + WIFI dual-core development board from Jieli
. Power management, battery, amplifier, OLED, DAC, and UART functions have been removed,
retaining only analog input/output, buttons, USB, SD card, and basic power supply.
Official development documentation (SDK 1.0.3, version 1.1.0 or higher recommended):
https://doc.zh-jieli.com/AC79/zh-cn/release_v1.0.3/board_description/board_overview/index.html
Official schematic: Official developer version purchase link:
https://gitee.com/Jieli-Tech/fw-AC79_AIoT_SDK/tree/release/AC79NN_SDK_V1.0.3/doc/datasheet/AC791N%E8%A7%84%E6%A0%BC%E4%B9%A6/schematic/JL_AC79_DevKitBoard (The following is an attachment: https://item.taobao.com/item.htm?spm=a1z10.1-cs.w4004-22883854875.30.504d246b7hM503&id=668602916268&mt=) The FW and UFW flashing files, as well as my personal EQ tuning file, have been uploaded; see attachments. Additionally, this JL chip has a low-noise issue; the audio GND and power supply GND should not be on the same group. For example, if your audio output is from your computer motherboard, don't use the computer's USB power supply. Use a power adapter from a different location, a battery, or a power bank. However, if AGND and GND are not connected, when there is no audio input, the output AGND will float, resulting in significant noise. You can replace the 0-ohm resistor connecting GND and AGND with a 75-ohm resistor. This will reduce noise to almost inaudible levels without causing excessive floating noise from AGND when there is no input. 2. See the attached PSD file for color silkscreen printing . Copyright: YOSTAR PICTURES PIXIV. Used by: 111148581 아니아나 (Aniana) 111636787 ACh