M28 wireless DIY lossless on-board speaker circuit board audio receiver module
Module
Bluetooth Audio Receiver Module
MH-M28
Reference price
| 1: | $6.50 |
| 25: | $6.50 |
| 100: | $6.40 |
| 500: | $6.30 |
| 1000: | $6.20 |
| 5000: | $6.00 |
Product Information
M28 wireless DIY lossless on-board speaker circuit board audio receiver module
Model Number：M2021030:M28
This module mh-m18 / M28 / 38 is a low-power Bluetooth design scheme. It supports the latest Bluetooth 4.2 transmission and Bluetooth automatic back connection technology. Dual channel stereo playback is not damaged. After the module is connected to Bluetooth, Bluetooth wireless transmission can be realized quickly, which is very convenient. In an open environment, the Bluetooth connection distance can reach 20m. It is widely used in various Bluetooth audio reception, various audio DIY modification, etc.
Function
After the module is powered on, the mobile phone searches for the Bluetooth name mh-m18 / mh-m28 / mh-m38. After connecting Bluetooth, you can play music. Module blue indicator: when Bluetooth is not connected, the indicator flashes quickly; When Bluetooth is connected, the indicator is always on; When Bluetooth is playing, the indicator flashes slowly.
Tip
1． Signal interference: the Bluetooth antenna is easy to be interfered by high-frequency or strong electromagnetic signals. Try to put it away from the wireless transmission equipment, and the board should not be close to metal objects. Keep a certain distance. 2. If there is current sound on the power amplifier board, it is caused by ground wire interference. It is recommended not to use plug-in wire at the output end of Bluetooth module. The wire must be welded, especially the ground wire. Moreover, the wire should not be too long, the shorter the better, and thicker as possible. The audio ground is grounded on the power amplifier board and must be connected to the ground at the audio input end of the power amplifier. This grounding point can be welded at different positions to achieve the lowest current sound. It is recommended that Bluetooth and power amplifier board be powered separately to isolate Bluetooth ground and power amplifier ground. 3. Since this product is designed as a bare board, try not to touch the components on the board with your hands, which is easy to cause static electricity and burn the chip. 4. The Bluetooth audio module has very high requirements for power supply and will improve the quality of audio. It is recommended to add LC filter circuit, especially switching power supply, such as mobile phone charger. 5. The charging interface of this product is current limited charging mode without charging management. If lithium battery is used for power supply, please use the lithium battery with protective plate produced by regular manufacturers
Parameter
Power supply: √, audio headset interface: √, lithium battery power supply: √, Bluetooth version: Bluetooth v4.2, support Bluetooth protocols: hfpv1.7, a2dpv1.2, avrcpv1.5, avctpv1.2, avdtpv1.2, format support: support wav / wma / FLAC / APE / MP3 lossless decoding, stereo dual channel output, working voltage: 5v3.7v-4.2v, unconnected broadcast status: 5.5ma, connected working status: 20mA, Deep sleep 3ua, transmission distance: 20m, working temperature: – 40 ℃ – + 85 ℃, sensitivity: – 87dbm, Bluetooth version: Bluetooth chv4.2, support Bluetooth protocols: hfpv1.7, a2dpv1.2, avrcpv1.5, avctpv1.2, avdtpv1.2, format support: support wav / wma / FLAC / APE / MP3 lossless decoding, stereo dual channel output, working voltage: 5v3.7v-4.2v, unconnected broadcast status: 5.5ma, Connection working state: 20mA, deep sleep 3ua, transmission distance: 20m, working temperature: – 40 ℃ – + 85 ℃, sensitivity: – 87dbm
Pin
1: 5V (power supply positive 5V), 2: GND (power supply negative), 3: Vbat (lithium battery positive 3.7-4.2v), 4: l (left channel output), 5: R (right channel output), 6: agnd (audio ground)
Power Supply
you can directly use the 5V micro USB Android cable for power supply, or you can connect another 5V power supply or 3.7 lithium battery. Note that the power supply interfaces of 5V and 3.7V are different. The 5V voltage is connected to 5V and GND, and the 3.7 lithium battery is connected to Vbat and GND.
Audio Output
the headset can be directly connected to the 3.5mm audio interface, and can also be wired for audio input of the power amplifier board. The interface L / R / agnd can be directly wired.
