Antenna Voltage Control - Ant_Off - u-blox ZED-F9P Integration Manual

Figure 21: ZED-F9P antenna supervisor
The bias-t inductor must be chosen for multi-band operation; a value of 120 nH 5% is
required for our recommended Murata part if the current is limited below its 110 mA rating.
See Antenna bias
Circuit shows buffer [U4]. Buffer is not strictly necessary when supplied from VCC. It is only
required when supplying antenna voltage that is not obtained from or controlled by module
VCC or VCC_RF .
Part Recommendation
L1
C2 MURATA GRM033R71C103KE14
TYCO, 0.25PF, PESD0402-140 -55/+125C
Table 24: Recommended components for antenna supervisor

3.8.1 Antenna voltage control - ANT_OFF

Antenna status (as reported in UBX-MON-RF and UBX-INF-NOTICE messages) is not
reported unless the antenna voltage control has been enabled.
Enable the antenna
ANT_CFG_VOLTCTRL to true (1).
Result:
• UBX-MON-RF in u-center "Message View": Antenna status = OK. Antenna power status = ON
• ANT_OFF pin = active high to turn antenna off therefore the pin is low to enable an external
antenna.
Start-up message at power up if configuration stored:
$GNTXT,01,01,02,ANTSUPERV=AC *00
$GNTXT,01,01,02,ANTSTATUS=INIT*3B
UBX-18010802 - R08
Early production information
section for additional information.
voltage control
3 Receiver functionality
Comment
300mA and >500 Ω at L-band frequencies
CAP CER X7R 0402 10N 10% 16V
ESD protection diode on RF trace
by setting the configuration
ZED-F9P - Integration manual
item CFG-HW-
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