LTE Standard Module Series
EC21 Mini PCIe Hardware Design
EC21_Mini_PCIe_Hardware_Design 25 / 67
USIM_VDD
GND
USIM_RST
USIM_CLK
USIM_DATA
USIM_PRESENCE
100nF
GND
GND
33pF
33pF 33pF
VCC
RST
CLK
IO
VPP
GND
GND
USIM_VDD
15K
(U)SIM Card Connector
Module
0R
0R
0R
Figure 4: 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 for (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following
figure.
USIM_VDD
GND
USIM_RST
USIM_CLK
USIM_DATA
0R
0R
0R
100nF
GND
33pF 33pF 33pF
VCC
RST
CLK
IO
VPP
GND
GND
15K
USIM_VDD
(U)SIM Card Connector
Module
Figure 5: 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 (U)SIM circuit design: