Huawei Ascend G300 Maintenance Manual

U8815
Maintenance Manual
9 Principles and Failure Analysis
Issue 1.0 (2012-02-13)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
32
circuits: R204 and C232; R3101 and C3101, outputting the system main clock to the main
chip through the PM.
32.768 kHz crystal oscillator is input to PM8029 and then to the system through the PM.

Troubleshooting Process
Failure: The handset cannot be powered on, or easily stops working. Check the 32.768 kHz
crystal oscillator, and check whether signal is available and frequency is stable on crystal
oscillators X301 and U3101.
Solution: Replace X301 or U3101. If the problem persists, replace PM8029.
Table 9-3 describes the signals in the circuit diagram in this section.
Table 9-3 Description of the signals in the circuit diagram in this section
Signal
Description
Reference Measurement or
Wave Form
XTAL32K
_OUT
Input to the 32.768kHz main
clock
XTAL32K_IN
Output from the 32.768kHz
main clock
VREG_TCXO
19.2MHz crystal power supply
2.85 V
TRK_LO_ADJ
The control signal of 19.2MHz
output frequency
None
RTR6285_TCXO
Output from the 19.2MHz
clock
TCXO
Output from the 19.2MHz
clock
9.2.4 Flash Memory Circuit

Circuit block diagram
The following figures show the flash memory circuit diagrams.

Huawei Ascend G300 Specifications

General

Brand	Huawei
Model	Ascend G300
Category	Cell Phone
Language	English