LTE-A Module Series
EM120R-GL&EM160R-GL Hardware Design
EM120R-GL&EM160R-GL_Hardware_Design 36 / 79
A recommended compatible design of (U)SIM2 interface is shown below.
Module
(U)SIM Card
Connector
USIM2_DET
USIM2_DATA
USIM2_CLK
RST
CLK
CD
IO
USIM2_VDD
USIM2_VDD
USIM2_RST
VCC
GND
VPP
GND
TVS
Note:
The five 0
Ω resistors must be close to M.2 socket connector, and all other components should be close
to (U)SIM card connector in PCB layout.
48
46
44
40
42
10-20K
22
Ω
22
Ω
22
Ω
33 pF33 pF33 pF
100 nF
0
Ω
0
Ω
0
Ω
0
Ω
0
Ω
eSIM
Figure 20: Recommended Compatible Design of (U)SIM2 Interface
In order to enhance the reliability and availability of the (U)SIM card in
customers’ applications, follow the
criteria below when designing the (U)SIM circuit:
⚫
Keep placement of (U)SIM card connector as close as possible to the module. Keep the trace length
as less than 200 mm as possible.
⚫
Keep (U)SIM card signals away from RF and VCC traces.
⚫
Assure the ground between the module and the (U)SIM card connector short and wide. Keep the
trace width of ground and USIM_VDD no less than 0.5 mm to maintain the same electric potential.
⚫
To avoid cross-talk between USIM_DATA and USIM_CLK, keep them away from each other and
shield them with surrounded ground.
⚫
In order to offer good ESD protection, it is recommended to add a TVS diode array with parasitic
capacitance not exceeding 10 pF. The 22
Ω resistors should be added in series between the module
and the (U)SIM card connector so as to suppress EMI spurious transmission and enhance ESD
protection. The 33 pF capacitors are used to filter out RF interference. Note that the (U)SIM
peripheral circuit should be close to the (U)SIM card connector.
⚫
The pull-up resistor on USIM_DATA trace can improve anti-jamming capability when long layout trace
and sensitive occasion are applied, and should be placed close to the (U)SIM card connector.
“*” means under development.
NOTE