MC13201_07 Datasheet, PDF (23/28 Pages) Freescale Semiconductor, Inc – 2.4 GHz Low Power Transceiver for the IEEE® 802.15.4 Standard

Figure 14 also shows a dual antenna configuration where there is a RX antenna and a TX antenna. For the
receive side, the RX antenna is ac-coupled to the differential RFIN inputs and these capacitors along with
inductor L1 form a matching network. Inductors L2 and L3 are ac-coupled to ground to form a frequency
trap. For the transmit side, the TX antenna is connected to the differential PAO outputs, and inductors L4
and L5 provide DC-biasing to VDDA but are ac-isolated. CT_Bias is not required or used.
VDD
Ant
LNA
Sw
Balun
Bypass
RFIN_P (PAO_P)
RFIN_M (PAO_M)
MC13201
Balun
VDDA
Bypass
CT_Bia
s
PAO_P
PAO_M
Using External Antenna Switch with LNA
RX Antenna
L2
L3
L1
TX Antenna
Bypass
VDDA
Bypass
L4
L5
RFIN_P (PAO_P)
RFIN_M (PAO_M)
MC13201
CT_Bias
PAO_P
PAO_M
Using Dual Antenna
Figure 14. Dual Port RF Configuration Examples
MC13201 Technical Data, Rev. 1.1,
Freescale Semiconductor
23