Automotive Module Series
AG525R-GL QuecOpen
Hardware Design
AG525R-GL_QuecOpen_Hardware_Design 52 / 104
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 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 for filtering interference of EGSM900. Please note that the
(U)SIM peripheral circuit should be close to the (U)SIM card connector.
The pull-up resistor on USIM_DATA line can improve anti-jamming capability when long layout trace
and sensitive occasions are applied, and should be placed close to the (U)SIM card connector.
The load capacitance of (U)SIM interface will affect rise and fall time of the data exchange.
3.10. USB Interfaces
The module provides one USB 3.0 interface and one USB 2.0 interface which support SuperSpeed
(5 Gbps on USB 3.0) and High-Speed (480 Mbps on USB 2.0) modes.
The USB 3.0 interface is used for data communication with AP by default. The USB 2.0 interface supports
AT command communication, data transmission, software debugging, firmware upgrade and voice over
USB*.
Table 12: Pin Description of USB Interface
Pin Name
Pin No.
I/O
Description
Comment
USB_VBUS
84
DI
USB connection detect
USB_DP
85
AI/AO
USB differential data bus (+)
Compliant with USB 2.0
NOTE