UNICORECOMM UM982-EB, User Manual

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UM982-EB User Manual
10 Antenna circuit UC-08-M31 EN P1.0.3
V_BCKP.
4 Antenna circuit
4.1 Antenna Short Protection Circuit
The antenna short protection circuit consists of a load management chip and peripheral
circuits.
The 5 V power source supplies the antenna after passing through the load management
chip
.
When the current of the antenna circuit is greater than 100 mA, it will trigger short circuit
protection, and FLAGB will output low level signals.
Removing R88/R77 (or R7/R6) and soldering R79 (or R8), you can feed ANT1 (or ANT2)
bypassing the short protection circuit.
Ant1 Bias
Ant2 Bias
U2 FPF2004
U5 FPF2004
Figure 4-1 Antenna Short Protection Circuit