NXP Semiconductors MKW01Z128, Reference Manual

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System Considerations
MKW01xxRM Reference Manual, Rev. 3, 04/2016
4-16 Freescale Semiconductor, Inc.
• Inductor L8 and capacitor C19 provide an ac blocking network for the PA power supply.
• The remaining external components are a generalized RF network -
— Provides impedance match between the antenna and the transceiver RFIO
— Supports an elliptic-function low pass filter to provide TX harmonic trapping and out-of-band
suppression
— The topology for the RF matching network can be used over the various bands of interest with
changes in component values. Not all indicated components are used at all frequencies
Figure 4-5. Single Port RF Schematic (+13dBm)
4.6.3 Higher Output Power RF Configuration (Dual Port with Optional
External Power Amplifier)
The secondary RF configuration for the transceiver is a dual port mode (shown in Figure 4-6 ):
• Secondary PA output (PA_BOOST) is used as the TX port and the standard RFIO pin is used as the
RX port.
• Maximum output power from the PA_BOOST output is typ17 dBm into a 50 ohm load.
• Inductor L1 and capacitor C1 provide an ac blocking network for the PA_BOOST power supply.
• An external RF switch is required to enable the appropriate path to the antenna -
— The TX port (PA_BOOST network) is selected for transmit
— The RFIO port network is selected for receive
— Device control output RXTX can used to control the antenna switch
• An optional external power amplifier can be inserted between the device TX output and the
antenna switch to increase transmitted power up to typically about 1 W maximum.
C17
C 18
A2
AN T C19
L5
L6 L7
C20 C21
C 22 C23
C 24
L8
U 2
MC13213
RXTX
37
G ND _PA 2
38
VR_PA
42
P A_B OOS T
41
R FIO
39
G ND _PA 1
40
AC Blocking Network