Back Interface; Sim Interface - US Robotics Courier USR3500 Reference Manual

Reference Guide
Parameter
The USB feature can be activated by using the AT+WMFM=0,1,3 AT command.
Refer to the AT Commands Interface Guide at
more information regarding this AT command.
3.2.

Back Interface

Figure 21. USR3500 Back Interface
3.2.1.

SIM Interface

A SIM card can be directly connected to the USR3500 through the embedded SIM
socket. This interface controls 3V / 1V8 SIM cards and it is fully compliant with GSM
11.11 recommendations concerning SIM functions.
The SIM interface of the USR3500 is ESD protected. Transient overvoltage
protections in ESD are internally added on the signals connected to the SIM interface
in order to prevent any damage from electrostatic discharge.
The SIM interface uses 5 SIM signals, namely:
• SIM-VCC: SIM Power supply
• ~SIM-RST: Reset
• SIM-CLK: Clock
• SIM-IO: I/O Port
• SIMPRES: SIM card detection
I/O
Input Low
Output High
Output Low
Rev 1.0
Min Typ
0
0.36 0.38
0
http://www.usr.com/support/3500
Expansion Compartment
SIM Interface
LED Status Indicator
GPS RF Interface
Main RF Interface
Secondary RF Interface
1/27/14
Interfaces
Max Unit
0.01 V
0.44 V
0.01 V
for
30
30