High Fidelity Bluetooth Compatible Audio Module MH M18 M28 M38 Lossless Decoder Board for DIY Projects _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ (m18/m28/m38)--Decoder Board MH-M18/M28/M38 Wireless Stereo Music Module with Indicator Light Bluetooth-Compatible Audio Module HiFi DIY Modification Kit _x000D_ Feature: _x000D_ 1. Low Power Bluetooth-Compatible Design: This audio module features a low-power Bluetooth-Compatible design that supports the latest Bluetooth-Compatible 4.2 transmission technology, enabling quick and easy wireless connectivity between devices. _x000D_ 2. High-Fidelity Stereo Playback: With support for dual-channel stereo sound and lossless playback of WAV/WMA/FLAC/APE/MP3 files, this Bluetooth-Compatible audio module delivers high-fidelity sound quality that's perfect for audiophiles. _x000D_ 3. Automatic Reconnection: The module supports automatic reconnection technology, making it easy to connect to your device and start playing music instantly. _x000D_ 4. Easy to Use: Once powered on, your phone will automatically search for the MH-M18/M28/M38 Bluetooth-Compatible name, allowing you to connect quickly and play your favorite tunes right away. _x000D_ 5. Clear Indicators: The blue indicator light on the module offers clear indications of its status, with fast flashing indicating no connection, steady light indicating connection, and slow flashing indicating playback. Specification: _x000D_ MH-M18: _x000D_ The module interface adopts a half hole process, and customers can directly mount or weld it onto the board. _x000D_ Number Pin Description _x000D_ 1 KEY button control terminal (4 button functions, additional resistance required _x000D_ 2 MUTE mute control terminal (output high level 3.3V during mute, output low level during playback) _x000D_ 3 VCC power supply positive pole 5V (lithium battery 3.7V power supply requires short-circuit diode) _x000D_ 4 GND power supply negative pole _x000D_ 5 L left channel output _x000D_ 6 R right channel output _x000D_ MUTE mute control terminal: used to control the power amplifier board. When mute, MUTE outputs a high level of 3.3V, and when playing, it outputs a low level. _x000D_ KEY button control: This function requires additional connection of resistors and buttons to be implemented. _x000D_ Volume power off hold function: default output volume. Control the volume to increase or decrease by pressing the button. If the control volume is less than 15%, the volume output will be 15% after re powering on; If the control volume is greater than 15%, the original volume will remain unchanged after power on again. _x000D_ _x000D_ MH-M28: _x000D_ Number Pin Description _x000D_ 1 5V power supply positive 5V _x000D_ 2 GND power supply negative pole _x000D_ 3 VBAT lithium battery positive electrode 3.7-4.2V _x000D_ 4 L left channel output _x000D_ 5 R right channel output _x000D_ 6 AGND audio ground _x000D_ 1. Power supply: You can directly use the MICRO USB Android cable 5V for power supply, or you can also connect an additional 5V power supply or 3.7V lithium battery. Note that the power supply interfaces for 5V and 3.7V are different. The 5V voltage is connected to 5V and GND, and the 3.7V lithium battery is connected to VBAT and GND. _x000D_ 2. Audio output: The headphones can be directly connected to a 3.5mm audio interface or wired for audio input on the power amplifier board (as shown in the figure, the interface L/R/AGND can be directly wired). _x000D_ _x000D_ MH-M38: _x000D_ Number Pin Description _x000D_ 1 5V power supply positive 5V _x000D_ 2 GND power supply negative pole _x000D_ 3 VBAT lithium battery positive electrode 3.7-4.2V _x000D_ 4 L+/L-left channel output (directly connected to the speaker) _x000D_ 5 R+/R - Right channel output (directly connected to the speaker) _x000D_ 1. Power supply: You can directly use the MICRO USB Android cable 5V for power supply, or connect an additional 5V power supply or 3.7V lithium battery (as shown in the following figure). Note that the power supply interfaces for 5V and 3.7V are different. 5V is connected to 5V and GND, while 3.7V lithium batteries are connected to VBAT and GND. High working current 5V2A, it is recommended to use a 5V2A regulated power supply for power supply. _x000D_ 2. Supports USB sound card, driver free (plug and play). Connect the module to the computer using a USB data cable, and the computer can play music to output through the module amplifier _x000D_ 3. Audio output: Output left and right stereo audio signals, which can be connected to two 2-8 ohm and 3-5W speakers respectively, and use 4 ohm and 5W speakers for push and