UM220-IV L User Manual
UC-00-M15 EN R1.4
Hardware Design
17
If the user has a high requirement for ESD (higher than the maximum specification in User Manual),
the user should consider other method to feed the antenna rather than using the VCC_RF pin. In
this case, it is recommended to choose a power supply chip with high ESD protection level. 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 ESD damage or other Electrical Over-Stress
(EOS).
When the working voltage of the active antenna is not 3.3V, the antenna can be powered
by the external power supply.
If the antenna power supply and the module’s main supply VCC use the same power rail, the ESD,
surge and overvoltage from the antenna will have an effect on VCC, which may cause damage to
the module. Therefore, it’s recommended to design an independent power rail for the antenna to
reduce the possibility of damage to the module.
Coaxial Aerial Cable
UM220-IV L
VCC
UC6226
SAW
LNA
FB
VCC_RF
V_ANT
ANT_DET_N
RF_IN
GND
R1 10
Ω
10nF
L
DC-Block
100pF
68nH
DC
Active Antenna
Figure 4- 4 UM220-IV L Active Antenna Solution Powered by External Power Supply
