The function of MEMS silicon microphones is to receive sound
waves and convert them into corresponding mechanical vibrations,
and then generate corresponding electrical signals through
mechanical vibrations to complete the sound electric
conversion.
The commonly used MEMS silicon microphones include dynamic
microphones and capacitive microphones. Both microphones are
pressure type sound wave receiving devices that respond to sound
pressure at a certain point in space. And both of these are
passive microphones, but their working principles are
different.
Dynamic microphones are made based on the principle of
electromagnetic induction. The diaphragm that receives sound
waves is forced to vibrate, driving the coil in a constant
magnetic field to generate alternating induced electromotive
force, completing the conversion of sound energy to electrical
energy
Advantages: Simple structure and convenient use.
Disadvantages: Low sensitivity, narrow frequency range, and
poorer transient response compared to capacitive microphones.
Capacitive MEMS silicon microphone
A capacitive microphone forms a capacitor based on the diaphragm
that receives sound waves. After being forced to vibrate, its
capacitance undergoes a change, generating an AC voltage,
thereby completing the conversion of sound and electricity.
Advantages: Wide frequency domain, high sensitivity, low
distortion, and good sound quality
Disadvantages: Complex structure, high cost, limited storage and
usage conditions.
High quality dynamic MEMS silicon microphones are commonly used
in popular music and entertainment light music because they can
provide higher sound pressure levels and good fidelity.
Moreover, it has high reliability and does not require a power
supply voltage. Therefore, in general situations, especially in
sound reinforcement, dynamic microphones are often used.
Capacitor microphones have the characteristics of wide frequency
range, high sensitivity, low distortion, and good sound quality,
and are commonly used in recording and professional
performances.
When the power of the MEMS silicon microphone transmitting
device is turned off, the working display LED of the
transmitting device on the wireless microphone receiving device
will turn off. If you are using a professional performance
microphone and frequently check the working status of the
wireless receiving device during program switching, you can find
this phenomenon. However, if the mute switch of the MEMS silicon
microphone is turned on, most wireless microphone receiving
devices will not be able to display. The operator uses
headphones to monitor when the program alternates.
To prevent the silence of MEMS silicon microphones, operators
should mute the wireless microphone transmitter and microphone
power switch before the performance, and fix the switch with
tape. If the MEMS silicon microphone switch has a protective
cover, it should be used every time it is used to keep the
wireless transmitting device and microphone in working condition
to ensure normal operation.
