Specifications

Table Of Contents
Cinterion
®
ALAS5V Hardware Interface Description
2.2 GSM/UMTS/LTE Antenna Interface
67
ALAS5V_HID_v00.030a 2019-03-20
Confidential / Preliminary
Page 54 of 124
Figure 21 shows the basic principles of an antenna detection circuit that is able to detect an-
tennas and verify their connection status. The GPIO pads can be employed to enable the an-
tenna detection, the ADCx_IN pads can be used to measure the voltage of external devices
connected to these ADC input pads - thus determining R
ANT
values. The AT^SRADC write com-
mand configures the parameters required for ADC measurement and returns the measurement
result(s) - for command details see [1].
Figure 21: Basic circuit for antenna detection
The following Table 14 lists possible signal states for the GPIOx signal lines in case these lines
are configured and used for antenna detection. For GPIO configuration and control commands
see [1].
Table 14: Possible GPIOx signal states if used for antenna diagnosis
Signal state Meaning
GPIOx:
Input Pull down or Output low
Output high
Antenna detection control (S1 in above figure):
Off (diagnostic measurement is off)
On (diagnostic measurement is on)
~
Antenna1..2
R
Ant
SC1 SC2
8..36V
-0.8V..+0.8V
0..5 kHz
1.6 Vpp
R
i
= 5 Ohm
6k..12k
R1
ADC1..2_IN
R2
R3
L1 S1
V
ADC
GPIOx
BATT+
appr.
0.7V + V
BATT+
ANT _M AIN
..
ANT_DRX_MIMO
Module
ANT1..2