2
1.2
Antenna Detection
SAW
LNA
Main Supply: 1.20V~1.98V
IO Supply: 1.77V~1.88V
Backup Supply: 1.65V~3.6V
RF, Short 50ohm Line
TCXO
VANT
:
+3.3 V
UC6226-QFN40
Antenna State
OPEN_DET
SHORT_DET
Open circuit
1
0
Short circuit
0
1
Normal
0
0
In the figure above, “VANT” is a standard power supply of +3.3 V which feeds the
antenna through a 33 nH inductor L5 at the upper right. When designing PCB layout, the
distance between the inductor L5 and the node that connects ANT_IN and the RF line
should be as short as possible—it is recommended to place one of the metal pads of the
L5 inductor on the RF line. “OPEN_DET” and “SHORT_DET” are status indicators of the
antenna.
When designing circuits, please note that the antenna power supply voltage should be
+3.3V, and the current should not exceed 80 mA. If the voltage or current is beyond that
range, the circuit parameters need to be adjusted to ensure that SHORT_DET and
OPEN_DET signals match the state values in the above table.
