Mạch giải mã âm thanh Bluetooth XH M18/M28/M38

- KEY: The end button control (4 keys function, need to add another resistor - MUTE: The mute control end (mute when 3.3 V, output level play when output low level) - VCC: The positive 5 V power supply (3.7 V lithium battery power supply need to short circuit diode) - GND: Power supply cathode - L: The left sound channel output - R: The right sound channel output Sơ đồ chân M28 - 5V: The positive 5 v power supply - GND: Power supply cathode - VBAT: The positive 3.7 4.2 V lithium battery