Origin:Mainland China
Product Introduction:
This product MH-M18/M28/M38 is a low-power Bluetooth design solution that supports new Bluetooth 4.2 transmission and lossless stereo playback. After the module is connected to Bluetooth, it can quickly achieve Bluetooth wireless transmission, which is very convenient. In an open environment, the Bluetooth connection distance can reach up to 20 meters.
Widely used in various Bluetooth audio receivers, DIY modification of various audio systems, etc
Function Description:
1. Bluetooth V4.2 version, supports Bluetooth automatic reconnection technology, supports WAV/WMA/FLAC/APE/MP3 lossless
Decoding, stereo dual channel output
After the module is powered on, the phone searches for the Bluetooth name MH-M18/MH-M28/MH-M38 and connects to Bluetooth
Afterwards, music can be played;
3. Blue indicator light for module:
When Bluetooth is not connected, the indicator light flashes rapidly;
When Bluetooth is connected, the indicator light stays on;
When Bluetooth is playing, the indicator light flashes slowly.
MH-M18 :
The module interface adopts a half hole process, and customers can directly mount or solder it onto the board.
Number Pin Description
1 KEY Button control terminal (4 button functions, additional resistors required)
2 MUTE Mute control terminal (outputs high level 3.3V during mute and low level during playback)
3 VCC Positive pole of power supply 5V (lithium battery 3.7V power supply requires short-circuit diode)
4 GND Negative pole of power supply
5 L Left channel output
6 R Right channel output
MUTE mute control terminal: Used to control the power amplifier board, MUTE outputs a high level 3.3V during mute and a low level during playback.
KEY button control: This function requires additional connection of resistors and buttons to achieve.
Volume power-off hold function: Default output volume. Control the volume increase and decrease through buttons. If the volume is controlled to be less than 15%,
the volume output will be 15% after powering on again; If the volume is controlled to be greater than 15%, the original volume will remain unchanged after powering on again.
·Precautions
1. Signal interference: Bluetooth antennas are extremely susceptible to high-frequency or strong electromagnetic signal interference, so try to place them away from the transmitter
as much as possibleA place to send wireless and other devices. And the board should not be in close proximity to metal objects, maintaining a certain distance.
2. If there is a current sound when connecting to the power amplifier board, it is caused by ground wire interference. It is recommended that the output end of the Bluetooth module
should not be plugged in, and must be soldered, especially for the ground wire. The wire should not be too long, the shorter the better, and it should be thicker as much as possible.
The issue of the audio ground being connected to the grounding point of the amplifier board requires it to be connected to the ground at the audio input end of the amplifier.
This grounding point can be welded at different positions to achieve the desired current and sound. Suggest separate power supply for Bluetooth and amplifier board, isolating
Bluetooth ground and amplifier ground.
3. Due to the bare board design of this product, try not to touch the components on the board with your hands as it may cause static electricity
The dead chip caused burning.
Warning: The charging interface of this product is limited to current charging mode and does not come with charging management!
For the safety of your life and property, please be sure to use lithium batteries with protective plates produced by legitimate manufacturers.
If any losses are caused due to improper use, our company will not be held responsible!
Additionally, when using MH-M18, the following two points should be noted:
Power supply: default 5V power supply. If you need to use a 3.7V lithium battery for power supply, you need to replace the diode with a 0-ohm resistor of 0603,
or simply short-circuit the two ends of the solder pad.
The Bluetooth audio module has very high requirements for power supply, which can affect the quality of audio. It is recommended to add LC filtering circuit,
especially switch power supply (such as mobile phone charger, etc.).
MUTE mute port: This module outputs a high level of 3.3V when muted and a low level of 0V when played. If the amplifier board mute high level is effective,
it can be directly connected. If the mute of the power amplifier board is controlled at a low level, a reverse circuit needs to be added.
Vrátenie peňazí za nedoručenie
