Dongguan Sheng Chang Electronic Technology Co., Ltd.


Years of focus
Buzzer / atomizer products


The technical specification of the microphone is Test conditions for microcephaly; The use of MIC should specify its working voltage and load resistance, and its sensitivity is significantly affected by different conditions of use Voltage resistance
1. Consumption current: the operating current of the microphone is The microphone head is mainly the current of FET at VSG=0. It can make a microphone with different working current according to the division of FET. However, when the working voltage is low and the load resistance is high, there are strict requirements for the working current. According to the electric schematic diagram, is known
V = the VSD + ID * RLID = (v - the VSD)/RL
Where, the current of IDFET at VSG equals to zero is RL is load resistance VSD, i.e. voltage drop between S and D of FET V is the standard operating voltage The general requirement is 100 outlets A< IDS < 500 outlets A

2. Sensitivity: the ability to generate voltage under unit sound pressure. Microphones
Unit: V/Pa or dBV/Pa some companies use dBV/Pa Bar - DBV/Pa = 40-60 DBV/mu Bar
0 DBV/Pa = 1 v/Pa

3. Output impedance: basically equivalent to the load resistance RL(1-70%).
4. Directivity and frequency response characteristic curve: A. Omnidirectional: the sensitivity of MIC is equal in different directions at the same distance. The structure of omnidirectional MIC is sealed on the PCB. Microphones
Frequency characteristic diagram: B, one-way directional unidirectional MIC, if the MIC sounds Kong Zheng to sound source to 0 degrees, so high sensitivity at 0 degrees, 180 degrees low sensitivity, a heart-shaped figure, the structure of the unidirectional MIC with omnidirectional MIC is different, it is open with some holes on the PCB, the sound from the sound hole and the hole of PCB, and MIC is equipped with sound-absorbing material, thus is the MIC between pressure and differential pressure. Microphones
Frequency characteristic diagram: C, de-noising type: it belongs to differential pressure MIC, which differs from one-way MIC in that there is no sound absorbing material inside. Its directional pattern is an 8 font Frequency characteristic:

5. Frequency range: Omnidirectional: 50~12000Hz20~16000Hz One-way: 100~12000Hz100~16000Hz Noise reduction: 100~10000Hz

6. Maximum pressure level: refers to the sound pressure level when the MIC distortion is at 3% MaxSPL is 115dBSPLASPL sound pressure level A is A weight

7. S/N SNR: that is, the ratio of the sensitivity of MIC to the noise of microphone itself under the same conditions. Please refer to the product manual for details