Audio Interface - Huawei MU709s-2 Hardware Manual

HUAWEI MU709s-2 HSPA+ Mini PCIe Module
Hardware Guide
Figure 3-6 Circuit of the USIM card interface
 To meet the requirements of 3GPP TS 51.010-1 protocols and electromagnetic
compatibility (EMC) authentication, the USIM socket should be placed near the
PCIe interface (it is recommended that the PCB circuit connects the PCIe interface
and the USIM socket does not exceed 100 mm), because a long circuit may lead to
wave distortion, thus affecting signal quality.
 It is recommended that you wrap the area adjacent to the USIM_CLK and
USIM_DATA signal wires with ground. The Ground pin of the USIM socket and the
Ground pin of the USIM card must be well connected to the power Ground pin
supplying power to the PCIe Adapter.
A 100 nF capacitor and1 μF capacitor are placed between the USIM_PWR and

Ground pins in a parallel manner (If USIM_PWR circuit is too long, that the larger
capacitance such as 4.7 μF can be employed if necessary). Three 33 pF
capacitors are placed between the USIM_DATA and Ground pins, the
USIM_RESET and Ground pins, and the USIM_CLK and Ground pins in parallel to
filter interference from RF signals.

It is recommended to take electrostatic discharge (ESD) protection measures near
the USIM card socket. The TVS diode with Vrwm of 5 V and junction capacitance
less than 10 pF must be placed as close as possible to the USIM socket, and the
Ground pin of the ESD protection component is well connected to the power
Ground pin that supplies power to the PCIe Adapter.

3.8 Audio Interface

The MU709s-2 Mini PCIe module provides one PCM digital audio interface. Table 3-6
lists the signals on the digital audio interface.
Issue 02 (2014-09-18)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Description of the Application Interfaces
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