Figure 4-11 Working Principles Of The Emmc Circuit; Table 4-5 Definitions Of Signals Of The Emmc Circuit - Huawei MediaPad 10 fhd Maintenance Manual

MediaPad10 FHD Maintenance Manual

Figure 4-11 Working principles of the eMMC circuit

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Table 4-5 lists the signals of the eMMC circuit.

Table 4-5 Definitions of signals of the eMMC circuit

Signal Name
EMMC_DATA[0:7]
PMU_RST2_N1
EMMC_CLK
EMMC_CMD
VREG_EMMC_1V8
VOUT0_2V85
Working Principles of the MIC Circuit
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Circuit analysis
The circuit supports 8-bit SDIO interfaces.
The I/O power pin VOUT5_1V8 and the power supply pin VOUT0_2V85 need to meet
certain sequencing requirements.
The reset signal PMU_RST2_N comes from the PMU. Its signal level is 2.6 V. This
signal experiences voltage dividing by a resistor before it is sent to the eMMC.
Fault analysis and location
Symptom: The eMMC circuit seldom fails. Peripheral circuits, however, may have
problems such as poor soldering and component defects. For example, the U1103 is a
power-on sequencing control component and may fail in certain conditions.
Circuit signals
Function
Data bus of the eMMC
Reset signal of the eMMC
Clock signal of the eMMC
Command signal of the eMMC
I/O power of the eMMC
Internal working power supply of
the eMMC
Working principles
Huawei Confidential
INTERNAL
Test Reference Value or
Oscillogram
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