Peripheral Circuits; Display Screen - Huawei U8815 Maintenance Manual

U8815
Maintenance Manual
Signal
VBAT
VREG_TCXO
TX_ON
TX_Q_P
TX_Q_M
TX_I_P
TX_I_M
TX_IREF
SSBDT_RTR6285A
PRX_Q_P
PRX_Q_M
PRX_I_P
PRX_I_M
DRX_GPS_Q_P
DRX_GPS_Q_M
DRX_GPS_I_P
DRX_GPS_I_M
PA_ON0
PA_ON1
PA_ON2
PA_RANGE0
PA_RANGE1

9.4 Peripheral Circuits

9.4.1 Display Screen


The following figures show display screen circuit diagrams.
Issue 1.0 (2012-02-13)
Description
Supplies 3.7 V voltage for Wi-Fi and Bluetooth
(BT)
RF switch power supply
Enables RTR6285A.
Q signal of the transmitting baseband
Q signal of the transmitting baseband
I signal of the transmitting baseband
I signal of the transmitting baseband
Reference voltage of the RTR transmission
SSBI data line
IQ signal of the primary receiving channel
IQ signal of the primary receiving channel
IQ signal of the primary receiving channel
IQ signal of the primary receiving channel
IQ signal of the secondary receiving channel
IQ signal of the secondary receiving channel
IQ signal of the secondary receiving channel
IQ signal of the secondary receiving channel
Controls the W2100 band PA.
Controls the W850 or W900 band PA.
Controls the W1900 or AWS band PA.
Adjusts the PA gain.
Adjusts the PA gain.
Circuit block diagram
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
9 Principles and Failure Analysis
Reference Measurement
or Wave Form
3.6 V
2.85 V
None
None
None
None
None
None
None
None
None
None
None
None
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