Integration Manual

Table Of Contents
SARA-R5 series - System integration manual
UBX-19041356 - R03 System description Page 31 of 123
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1.8 SIM interface
1.8.1 SIM card interface
SARA-R5 series modules provide on the VSIM, SIM_IO, SIM_CLK and SIM_RST pins a high-speed
SIM/ME interface including automatic detection and configuration of the voltage required by the
connected SIM card or chip.
Both 1.8 V and 3 V SIM types are supported. Activation and deactivation with automatic voltage
switch from 1.8 V to 3 V are implemented, according to ISO-IEC 7816-3 specifications. The VSIM
supply output provides internal short circuit protection to limit start-up current and protects the SIM
to short circuits.
1.8.2 SIM card detection interface (GPIO5)
The GPIO5 pin is configured as an external interrupt to detect the SIM card mechanical / physical
presence. The pin is configured as input with an internal active pull-down enabled, and it can sense
SIM card presence only if cleanly connected to the mechanical switch of a SIM card holder as
described in section 2.5:
Low logic level at GPIO5 input pin is recognized as SIM card not present
High logic level at GPIO5 input pin is recognized as SIM card present
The SIM card detection function provided by GPIO5 pin is an optional feature that can be implemented
or not according to the application requirements.
For more details, see the SARA-R5 series AT commands manual [2], +UGPIOC, +CIND and +CMER AT
commands.
1.9 Data communication interfaces
SARA-R5 series modules provide the following serial communication interfaces:
UART interfaces, available for communications with host application processor. See section 1.9.1.
USB 2.0 compliant interface, available for diagnostic only. See section 1.9.2.
SPI interfaces, available for communications with external SPI devices and for diagnostic. See
section 1.9.3.
SDIO interface, available for communications with external SDIO devices. See section 1.9.4.
DDC (I2C bus compatible) interface, available for communications with external I2C devices. See
section 1.9.5.