Flash Memory Circuit - Huawei U8860 Maintenance Manual

U8860
Maintenance Manual
Clock
32.768 K crystal for platform
use
BT&WiFi in 37.4 MHz
Troubleshooting process
Failures:
The phone cannot be powered on or frequently freezes. X401's test result shows that X401 has
no outputs or its output frequencies are unstable.
Solution: Replace X401.
Description of the signals in the circuit diagram in this section
Signal
XTAL_19M
_OUT
XTAL_19M
_IN

9.2.4 Flash Memory Circuit

The MSM8255-0 is able to visit the LPDDR2 through two high-speed buses (EBI0/EBI1).
The LPDDR2 is connected to the MSM8255-0 in PoP (Package-on-package) mode.
Meanwhile, the MSM8255-0 also can visit the external storage eMMC through a low-speed
bus (EBI2), as shown in the following figure.
Issue 1.0 (2011-11-14)
Effect
MSM8255 sleep clock signal
BCM4329 clock
Description
Output from the 19.2 MHz
main clock
Input to the 19.2 MHz main
clock
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9 Principles and Troubleshooting
Reference Measurement or Wave
Form
Remarks
BCM4329
40