Huawei Y511-U030 Repair Manual page 45

XXXX The basic version Repair Manual
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Circuit analysis:
Baseband chip master clock has a 26M TCXO, in the normal work of the system, provide the
basic frequency for BBIC and TRANSEIVER; sleep clock from a clock clock (32.768Hz) circuit, a
RTC circuit in the system clock source, a dormant or shutdown state, to keep the system time or
timing function, to reduce the system power consumption. 32.768kHz crystal clock circuit needs
an external input, output, the crystal at both ends are respectively connected with the baseband
chip clock driver. As the clock bad will lead to not boot failure.
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Fault analysis and treatment process:
Can not boot failure, can first check whether 32K clock, connected welding. The output and
measurement of TCXO is normal, if not normal, need to be replaced.
2013-09-25
V1.0
华为机密，未经许可不得扩散
internal public
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