ESP8266 (WEMOS D1 MINI) and VS1003/53 WIFI RADIO

Context: Project involves creating a Wi-Fi radio for a charity based hospital radio. The project is based on NodeMCU using a WEMOS D1 mini as the MCU. The other main components are a 128x160 tft display amplifier modeul and a VS1003/53 module.

WEMOS MODULE USED

MP3 CODEC USED / VS1053 MODULE

Class D Amplifier initially used

Linear Amplifier now used

The whole project is based off of the ESP-radio.pdf file attached and the wiring is exactly shown in the guide.

Problem:

The radio unit needs to be ran off of a single supply / mains supply as batteries are not permitted. I have a dual 12V (1A) / 5V (4A) supply that I am currently using. However as mentioned in the pdf the amplifier should be driven off a battery as running it of the same supply produces a great deal of noise.

To combat this Ive replaced the class D amp with a linear amp but the output of the VS1053 module still produces both low frequency clicking and high frequency whining noises.

To attempt to combat this ive tried a simple first order reconstruction filter (100nF + 100ohm ~ Fc=15Khz) as well as removing the DC offset from signal lines (As recommended in section 3.2 of vs10XXan_output.pdf) but im still getting noise issues and getting pretty stuck with how to go about removing them. I beleive the main reason for the noise is because the output of the VS1053 module is intended for a 30ohm isolated headphone load (hence biasing at 1.25v) and I am trying to use an amplifier referenced to ground

Any help appreciated,

Thanks

Andy

ESP-radio.pdf (1.16 MB)

vs10XXan_output.pdf (531 KB)

Interesting project.