Product Info

Automotive Module Series
AG521R-NA QuecOpen Hardware Design
AG521R-NA_QuecOpen_Hardware_Design 49 / 92
Module
USIM_VDD
USIM_RST
USIM_CLK
USIM_DATA
USIM_DET
22R
22R
22R
VDD_EXT
470K
100 nF (U)SIM Card Connector
GND
GND
VCC
RST
CLK
IO
VPP
GND
USIM_VDD
10K
33 pF 33 pF33 pF
CD1 CD2
Figure 18: Reference Circuit of (U)SIM Interface with an 8-Pin (U)SIM Card Connector
If (U)SIM card detection function is not needed, keep USIM_DET disconnected.
A reference circuit for (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following figure.
Module
USIM_VDD
USIM_RST
USIM_CLK
USIM_DATA
22R
22R
22R
100 nF
(U)SIM Card Connector
GND
VCC
RST
CLK IO
VPP
GND
10K
USIM_VDD
33 pF 33 pF33 pF
Figure 19: Reference Circuit of (U)SIM Interface with a 6-Pin (U)SIM Card Connector
To enhance the reliability and availability of the (U)SIM card, follow the criteria below in the (U)SIM circuit
design:
⚫ Keep the placement of (U)SIM card connector as close to the module as possible. Keep the trace length as less
than 200 mm as possible.
⚫ Keep (U)SIM card signals away from RF and VBAT traces.
⚫ Assure the trace between the ground of the module and that of 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