Update: At present I don’t have the SD card connector circuit diagram. Please don’t post in the comments asking for the circuit.
Long back in my blog I had posted how to make an USB mp3 player.
This mp3 player is made using a Chinese mp3 decoder board. Find more about the mp3 decoder board at http://www.vire.net.cn/
You don’t have to order it from china. It is available from most of the local electronic shops in INDIA. I don’t know about other countries.
The board is self explanatory. It has proper silk screen markings which shows how to connect. But still many had posted comments in my blog for the connection diagram of this board. I think it is hard for an electronics beginner to connect the board. So I thought of posting the connection diagram.
On the rear side of the board, there are three connectors.
They are for
1) Player buttons and IR sensor
2) USB and MMC/SD card interface
3) Power supply
For the board to play music, it needs a 5V DC power supply, USB port, 3.5mm stereo jack and an IR sensor to detect the signals from remote. You can also add switches to control songs, SD/MMC card slot, antenna for clear radio reception. All these are optional.
The connection diagram doesn’t show how to connect an SD/MMC card socket. You can connect the SD/MMC to this player using an USB card reader.
Be careful while connecting the USB socket. If there is a connection mistake, it can damage your flash drive. Cross check the connection with the below image.
Bill of Materials
MP3 Player board + Remote Controller
3.5mm stereo jack
IR sensor (3.3v)
5V power supply
SD/MMC card socket (optional)
NOTE: This is not an open Hardware project because the circuit diagram and PCB layout is not available from the vendor 🙁