USB MP3 Decoder Board Built in amp and TF Card

Module highlights:
Ultra strong sound quality, onboard 2W mono amplifier (5V power supply can reach up to 3W), directly connected
to the speaker (recommended to be paired with 4 Ω 3W speaker), 3.5mm gold-plated headphone jack can be used to connect to headphones or external speakers. 
 
Equipped with MicroUSB power interface, it can be powered by mobile power or USB charger through
mobile phone data cable, or by 3.7V lithium battery and USB 5V power. 
 
Support TF card (mobile phone storage card) and USB playback mode. 
 
Equipped with horn terminals that do not require welding, making wiring convenient. 
The module design is convenient for modification. 
 
Schematic diagram: http://www.chipkingdom.com/upfile/201531917474080714.pdf
 
Product Overview:
1) Supports MP3 format, automatically plays when powered on, and updates the red LED indicator when playing. 
2) Supports USB flash drive (tested 32GB) and TF card (tested 16GB) playback modes; The default TF card mode is when powered on. If the TF card does not automatically jump to USB mode and both devices are installed, the playback mode can be manually set. Please refer to the button operation instructions for details. 
3) The buttons can adjust the up and down track switching, volume+-, pause/play, and mode switching. Please refer to the button operation instructions for details. 
4) You can set the "single/full track" cycle with the button, and the default full track cycle is when powered on. Press the "Repeat" button to change the cycle mode
 
Key operation instructions 
"Prev/V -" key: "Short press" to switch to "Previous" song, "Long press" to "Volume decrease"
"Next/v++" key: "Short press" to switch to "next" song, "Long press" to "volume increase" 
"P/P/Mode" key: "Short press" switches to "play/pause", "Long press" switches to USB flash drive, TF card "mode" selection 
"Repeat" key: "Short press" to cycle between "single/full track" (without long press function) 
Note: 1. Press and hold for approximately 2 seconds 
 
2. If using USB flash drive mode, it is recommended to supply 5V power. Some USB flash drives do not support 3.7V power supply.
 
Product specification parameters Power supply range: 3.7~5.5V 
Product size: 45mm * 36mm