User Manual
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Select the microphone with the sensitivity lower than -51.5dB since the max. gain in MIC1 can
reach 51.5dB. The level of MIC_P1 is about 1.73V.
Note: In order to get better audio effect for users, we present the following suggestions:
1
)
During the process of using MG2639_V3 module, it’s advised to use 100pf & 33pf capacitance on its
external audio path, and serially connect with the beads to improve the audio quality.
2
)
Connect TVS tube or pressure sensitive resistance on the audio path (approaching the module’s
interface) to prevent the ESD from damaging the module.
3
)
Make sure the use environment and module are well grounded and there is no mutual influence.
4
)
The power ripple supplied to the module is less than 50mV.
4.5
Charging interface
The PINs used for MG2639_V3 module’s charging interface are 23-27 PINs. See the charging
external connection in the figure below: D3 adopts CJ10P20DE6G or MBT35200MT1; VT1 adopts
2SK3019, NTA4001NT1 or SSM3K15FS; R1 is 0.2Ω current inspection resistance, which requires
1206 encapsulation.
Figure 4-9 Charging interface circuit reference design principle diagram