Circuit Recommended For The Usim Card Interface - Huawei MU709 Series Hardware Manual

HUAWEI MU709 Series HSPA+ Mini PCIe Module
Hardware Guide
PIN Pin Name Pad
No. Type
8 USIM_PWR PO

3.6.2 Circuit Recommended for the USIM Card Interface

As the Mini PCIe Adapter is not equipped with a USIM socket, you need to place a
USIM socket on the user interface board. Figure 3-9 shows the circuit of the USIM
card interface.
Figure 3-9 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
Description Parameter
Power source
-
for the
external USIM
-
card
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd
Issue 04 (2015-06-25)
Description of the Application Interfaces
Min. (V) Typ. Max. (V)
(V)
–0.3 1.8 1.98
–0.3 3.0 3.3
Comments
USIM_PWR=1.8
V
USIM_PWR=3.0
V
23