UM960L User Manual (Raw Data)
UC-00-M47 EN R1.0
Hardware Design
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3
Hardware Design
3.1
Antenna Feed Design
UM960L just supports feeding the antennal from the outside of the module rather than
the inside. It is recommended to use devices with high power and that can withstand
high voltage. Gas discharge tube, varistor, TVS tube and other high-power protective
devices may also be used in the power supply circuit to further protect the module from
lighting strike and surge.
UM960L
ANT_IN
ANT
VCC_RF
GND
C2
ANT_BIAS
L1
C1
D1
D2
Figure 3-1 UM960L External Antenna Feed Reference Circuit
Remarks:
L1: feed inductor, 68nH RF inductor in 0603 package is recommended;
C1: decoupling capacitor, it is recommended to connect two capacitors of
100nF/100pF in parallel;
C2: DC blocking capacitor, recommended 100pF capacitor;
Not recommended to take VCC_RF as ANT_BIAS to feed the antenna (VCC_RF is not
optimized for the anti-lighting strike and anti-surge due to the compact size of the
module)
D1: ESD diode, choose the ESD protection device that supports high frequency
signals (above 2000 MHz)
D2: TVS diode, choose the TVS diode with appropriate clamping specification
according to the requirement of feed voltage and antenna voltage
