5. Radio
5.1 RF Section
This section gives a short introduction to the RF section of the BRD2601B board.
The schematic of the RF section is shown in the figure below.
2.4 GHz
Matching
Network
Supply
Filtering
High
Frequency
Crystal
Chip Antenna and
Antenna Matching Network
VDCDC
GND
GND
GND
GND
GND
GND
C11
2U2
X1
39.000 MHz
3
1
2
4
C18
1U
C5
NM
C6
1P5
ANT1
2450AT18D0100
GND
2
IN
1
GND
3
GND
4
L3
1N5
C4
1P6
C12
18P
C2
18P
L5
BLM03AG700SN1D
L2
1N7
C19
120P
C3
2P3
Gr ound
RF I / O
RF Cr ys t a l
RF Ana l og Powe r
PA Powe r
U1B
EFR32MG24B310F1536IM48-B
2G4RF1
16
RFVDD
14
HFXTAL_I
11
HFXTAL_O
12
PAVDD
17
RFVSS
15
L1
2N5
L4
BLM03AG700SN1D
Figure 5.1. Schematic of the RF section
5.1.1 RF Matching Description
The EFR32MG24 RF port impedance is matched to 50 Ohm: the 2G4RF1 pin is connected to a four-element impedance matching and
harmonic filter circuitry and a DC blocking capacitor. The on-board ceramic antenna is also matched to 50 Ohm by its impedance
matching components and connected to the EFR32MG24.
5.1.2 RF Section Power Supply
On the BRD2601B, the supply for the radio (RFVDD) and the power amplifier (PAVDD) is connected to the on-chip DC-DC converter.
By default, the DC-DC converter provides 1.8 V for the entire RF section (for details, see the schematic of the BRD2601B).
5.1.3 RF Matching Bill of Materials
The bill of materials for the BRD2601B RF matching network is shown in the following table.
Table 5.1. Bill of Materials of the BRD2601B RF Matching Network
Component name
Value
Manufacturer
Part Number
L1
2.5 nH
Murata
LQP03HQ2N5B02
L2
1.7 nH
Murata
LQP03HQ1N7B02
C2
18 pF
Murata
GJM0335C1E180GB01D
C3
2.3 pF
Murata
GRM0335C1H2R3WA01D
C4
1.6 pF
Murata
GRM0335C1H1R6WA01D
UG524: xG24 Dev Kit User's Guide
Radio
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