Mobile Phone STORM (Smartphone)
Service Manual
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10
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3.3 RF Chip WTR4905 device introduction
The WTR4x05 device is a highly-integrated multimode, multiband RF CMOS transceiver IC. The
WTR4x05 device cannot be used as stand-alone on MSM9x35/MSM8994
andMDM9x40/MDM9x45 modems.
All chipsets support advance RF techniques by adding a second RFIC
WTR4905-baseddesigns
– Add WTR2100 to support DSDA and/or SG-LTE
– Add WTR2605 to support SV-LTE
WTR3925-based designs supporting MSM8994, MSM8996, MDM9x35M, MDM9x45,
and Fusion 4.5
– Add WTR4605 to support DSDA, SG-LTE, and/or SV-LTE
It integrates RF
receive and transmit features into a 3.22 × 3.22 × 0.57 mm package to simplify handset
design, minimize parts count, and reduce DC power consumption.
3.4 Interface Functional Circuit
3.4.1 Charging Circuit
Figure 3.4.1-STORM Charging Circuit
