Huawei Y300 Maintenance Manual page 35

Y300 Maintenance Manual
Figure 9-3 Circuit diagram for startup management (2)
Analysis
The Y300 adopts the independent power management chip PM8029. The PM8029's startup
process is controlled by Qualcomm's codes. When the PM8029 detects that the
KPD_PWR_ON level is low, the PM8029 enables the startup process. During the startup
process, the PM8029 converts the main power supply voltage (VHP-PWR) to voltages shown
in Figure 9-4
Issue 1.0 (2013-01-24) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
9 Principles and Failure Analysis
30