M28 Audio Bluetooth Module

MH-M28 is a low power Bluetooth design solution that supports the latest Bluetooth 4.2 transmission, two channel stereo lossless playback and Bluetooth wireless transmission when the module is connected to Bluetooth, which is very convenient. In an open environment, the Bluetooth connection distance can be up to 20 meters. Widely used in a variety of Bluetooth audio reception, a variety of DIY audio modification.
M28 module has headphone jack audio port for connecting headphone and 3.5mm audio device.

M28 Module:

Mute Control Terminal: Used to control the power amplifier board. When muting, muting produces a high level of 3.3v and produces a low level during playback.

Key Control: This function requires additional connection of resistors and buttons.

Volume off function: The default output is 100% volume. Press the button to control volume increase and decrease. If the control volume is less than 15%, the volume output will be 15% after feedback; if the control volume is greater than 15%, the original volume will remain unchanged after activation.

Pin Function Description:

1. key button: control terminal (4 button functions include additional resistors such as wiring diagrams)
2. MUTE: mute control terminals (Mute output high level 3.3V, output low level when playing)
3. VCC: positive power supply 5 V (lithium battery 3.7 V power supply requires short circuit diode)
4. GND: power negative/audio signal glands
5. L: left channel output
6. R: Right Channel Output

MH-M28 Module Application:

1. Conversion of old speakers into Bluetooth speaker
2. DIY Bluetooth speakers

MH-M28 Module Specification:

1. Model: MH-M28
2. Bluetooth Version: Bluetooth 4.2
3. Operating Voltage: 3.7 ~ 5VDC
4. Max. Operating Current: 20mA
5. Broadcast status not connected: current is 5.5mA
6. Connection work status: 20mA
7. Deep Sleep: 3uA
8. Transmission distance: 20 meters
9. Operating Temperature: -40 to 85°C
10. Support WAV/WMA/FLAC/APE/MP3 lossless decoding, stereo two-channel output
11. Support Bluetooth Protocol HFPV1.7, A2DPV1.2, AVRCPV1.5, AVCTPV1.2, AVDTPV1.2
12. Maximum Transmission Distance of 20 meters.
13. Can be powered via a lithium Battery.
14. Sensitivity: -87dbm
15. Length: 45mm
16. Width: 20mm
17. Height: 2mm