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HUAWEI ME909u-521 LTE LGA Module
Hardware Guide
Description of the Application Interfaces
Issue 05 (2017-12-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
42
JTAG reset pin of ME909u-521 module is different from HUAWEI's other LGA
modules, for example: MU509, MC509 and MU609.
JTAG_SRST_N must be dealt with ESD protection as follow. The 1 k
Ω resistor and
4.7 nF capacitor must be placed as close as possible to ME909u-521 module.
Figure 3-18
ESD protection of JTAG_SRST_N
3.11 RF Antenna Interface
The ME909u-521 module provides three antenna pads (MAIN_ANT, GPS_ANT and
AUX_ANT) for connecting the external antennas.
The RF pad difference is the most important difference between HUAWEI LGA
modules, please refer to HUAWEI 30 mm x 30 mm LGA Module Hardware Migration
Guide.
Route the antenna pad as close as possible to antenna connector. In addition, the
impedance of RF signal trace
s must be 50 Ω.