Product Info

LTE Standard Module Series
EG91 Hardware Design
EG91_Hardware_Design 39 / 93
Module
USIM
_
VDD
USIM
_GND
USIM
_
RST
USIM
_
CLK
USIM
_
DATA
USIM
_
PRESENCE
0
R
0
R
0
R
VDD
_
EXT
51K
100nF (U)SIM Card Connector
GND
GND
33pF
33pF
33pF
VCC
RST
CLK
IO
VPP
GND
GND
U
SIM
1
_
VDD
15
K
Figure 17: Reference Circuit of (U)SIM Interface with an 8-Pin (U)SIM Card Connector
If (U)SIM card detection function is not needed, please keep USIM_PRESENCE unconnected. A reference
circuit of (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following figure.
Module
USIM_
VDD
USIM_GND
USIM_RST
USIM_CLK
USIM_DATA
0R
0R
0
R
100nF
(U)SIM Card Connector
GND
33pF
33pF 33pF
VCC
RST
CLK IO
VPP
GND
GND
15K
USIM1_VDD
Figure 18: Reference Circuit of (U)SIM Interface with a 6-Pin (U)SIM Card Connector
In order to enhance the reliability and availability of the (U)SIM card in customers’ applications, please
follow the criteria below in the (U)SIM circuit design:
 Keep placement of (U)SIM card connector to the module as close as possible. Keep the trace length
as less than 200mm as possible.
 Keep (U)SIM card signals away from RF and VBAT traces.
 Assure the ground trace between the module and the (U)SIM card connector short and wide. Keep