Figure 4-12 Working Principles Of The Mic Circuit; Table 4-6 Definitions Of Signals Of The Mic Circuit - Huawei MediaPad 10 fhd Maintenance Manual

MediaPad10 FHD Maintenance Manual

Figure 4-12 Working principles of the MIC circuit

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Table 4-6 lists the signals of the MIC circuit.

Table 4-6 Definitions of signals of the MIC circuit

Signal Name
MICBIAS1
MIC1P
MIC1N
Working Principles of the Headset Circuit
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Figure 4-13 shows the working principles of the headset circuit.
2012-10-09
Circuit analysis
The MIC used on the PCBA comes from Knowles. The MIC bias voltage provided by
the PMU is input to the PMU after passing a single-ended-to-differential converter.
Fault analysis and location
Symptom: The MIC has a poor recording effect, or noise is heard.
Solution: Replace the MIC, and then check whether the fault is cleared. If the fault
persists, check whether the bias voltage is normal and whether the PMU U900 is faulty.
Circuit signals
Function
MIC bias voltage
MIC differential signal
MIC differential signal
Working principles
Huawei Confidential
Test Reference Value or Oscillogram
INTERNAL
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