to choose the microphone
According to the sound receiving range, the microphone is divided
into omnidirectional, unidirectional, and noise canceling. The noise
canceling microphone is designed to decay the low frequency far.
Most customers use omnidirectional microphone; the unidirectional
is only used in some special occasions, therefore we should pay
more attention to mechanical and circuit design.
Sensitivity: The sensitivity
of the microphone affects the recorded volume. However, high sensitivity
doesn’t mean a good microphone. The good circuit design is also
necessary for getting better results. We suggest selecting a middle
common sensitivity at beginning. Too high or too low might affect
the lead time and the price.
The test voltage and the impedance affect the sensitivity of the
microphone. Generally speaking, the higher the voltage and the impedance
is the better sensitivity we get. Therefore, the test condition
is for reference and IQC only, which is usually different to the
Dimension: Diameter is from 2mm to 14mm, height is from 1.1mm to
6.7mm. 4*1.5, 6*2.2, 6*2.7, 6*5.0, 9.7mm are common spec.
Connecting way: pin, solder pad, SMD, and contact. Due to the diaphragm
is easily damaged by high temp. during soldering, therefore we suggest
finishing the wires and test the microphone again by us to confirm
the stability of quality.
Our P/N example : AMB-O60F42-NWH
A = AATC
M = Microphone
B= Back type, F = Foil type, comparing with foil type, the back
type is steadier and has better low frequency response, the price
will be also higher.
O = Omnidirectional, U = Unidirectional, N = Noise cancelling
60 = Diameter 6.0mm, 97=9.7mm
F = Height 2.7mm, G = 2.2mm, H = 1.5mm, C=5.0mm
42 = Sensitivity -42dB,
N= No capacitance, A = Add one capacitance10p, B= 33p, C= 10+33p,
W = Wire, A= Soldering, B=PIN, C=Contact,
H = Rubber Holder