SARA-G3 series - System Integration Manual
UBX-13000995 - R06
Objective Specification
System description
Page 45 of 218
1.7.2
Antenna detection interface (ANT_DET)
SARA-G300 and SARA-G310 modules do not support antenna detection interface (
ANT_DET
).
The antenna detection is based on ADC measurement. The
ANT_DET
pin is an Analog to Digital
Converter (ADC) provided to sense the antenna presence.
The antenna detection function provided by
ANT_DET
pin is an optional feature that can be implemented if
the application requires it. The antenna detection is forced by the +UANTR AT command. Refer to the
u-
blox AT Commands Manual [2] for more details on this feature.
The
ANT_DET
pin generates a DC current (20 µA for 5.4 ms) and measures the resulting DC voltage,
thus determining the resistance from the antenna connector provided on the application board to GND. So,
the requirements to achieve antenna detection functionality are the following:
an RF antenna assembly with a built-in resistor (diagnostic circuit) must be used
an antenna detection circuit must be implemented on the application board
Refer to section 2.3.2 for antenna detection circuit on application board and diagnostic circuit on antenna
assembly design-in guidelines.
1.8
SIM interface
1.8.1
(U)SIM card interface
SARA-G3 modules provide a high-speed SIM/ME interface, including automatic detection and configuration
of the voltage required by the connected (U)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 is implemented, according to ISO-IEC 7816-3 specifications. The
VSIM
supply output
pin provides internal short circuit protection to limit start-up current and protect the device in short circuit
situations.
The SIM driver supports the PPS (Protocol and Parameter Selection) procedure for baud-rate selection,
according to the values determined by the SIM Card.
SIM Application Toolkit (R99) is supported only by SARA-G350 modules.
1.8.2
SIM card detection interface (SIM_DET)
Not supported by SARA-G300-00S and SARA-G310-00S modules.
The
SIM_DET
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 properly connected to the mechanical switch of a SIM card holder as described in
section 2.4:
Low logic level at
SIM_DET
input pin is recognized as SIM card not present
