G700-U10 Smartphone
Maintenance Manual
10 Circuit and Failure Analysis
Issue 1.0 (2013-07-22)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
72
Troubleshooting Process
Figure 10-46
Troubleshooting microphone failures
Microphone failure
Is the
microphone
normal?
N
Replace the
microphone
Y
Is the microphone
circuit normal?
N
Clear faults on the
circuit
Y
Replace
U401
Circuit Signals
Table 10-14
Circuit signals of this section
Signal Description
Reference Value or Waveform
VMIC
Microphone power supply
1.9 V
MICP0
Differential signal input's positive electrode
Analog differential signal
MICN0 Differential signal input's negative electrode Analog differential signal