Instruction Manual
Table Of Contents
- Table of Contents
- 1. Introduction
- 2. Radio Board Connector
- 3. Radio Board Block Summary
- 4. RF Section
- 5. Mechanical Details
- 6. EMC Compliance
- 7. RF Performance
- 8. EMC Compliance Recommendations
- 9. Board Revision History
- 10. Errata
- 11. Document Revision History
4. RF Section
4.1 Introduction
This section gives a short introduction to the RF section of the BRD4186C Radio Board.
4.2 RF Section Schematic
BRD4186C Radio Board RF section schematic is shown in the following figure.
GND
GND
PAVDD
VDCDC
GND
GNDGND GND
GND
GND
GND
P2
U.FL
3
2
1
C101
18P
AT1
INVERTED_F
CC1
Gr oun d
RF I / ORF Cr ys t a l
RF Ana l og Powe r
PA Powe r
U1B
EFR32MG24
2G4RF1
16
RFVDD
14
HFXTAL_I
11
HFXTAL_O
12
PAVDD
17
RFVSS
15
R1
0R
L102
BLM03AG700SN1D
L1
L103
BLM03AG700SN1D
C2
C102
2U2
X1
39.000 MHz
31
2
4
C105
120P
C106
1U
C1 C3
L3
0R
L2
R2
0R
NM
50R_P2
50R_IFA50R_L350R_R1
2.4 GHz
Matching
Network
Path
Selection
Inverted-F
Antenna
Supply
Filtering
UFL
Connector
Antenna
Tuning
Component
High
Frequency
Crystal
Figure 4.1. BRD4186C RF Section Schematic
4.2.1 2.4 GHz RF Matching Description
The 2.4 GHz RF matching connects the 2G4RF1 pin to the on-board printed IFA. The component values were optimized for the
2.4 GHz band RF performance and current consumption with the targeted 10 dBm output power.
The matching network consists of a five-element impedance matching and harmonic filter circuitry and a DC blocking capacitor (not
required for the 20 dBm part).
For conducted measurements, the matching network output can also be connected to the UFL connector by removing the series R1
resistor (0 Ohm) between the antenna and the matching network and mounting it to the R2 resistor position between the matching net-
work and the UFL connector.
4.3 Bill of Materials for the 2.4 GHz Matching Network
The bill of materials for the BRD4186C Radio Board 2.4 GHz matching network is shown in the following table.
Table 4.1. Bill of Materials for the BRD4186C 2.4 GHz RF Matching Network
Component Name Value Manufacturer Part Number
L1 2.5 nH Murata LQP03HQ2N5B02D
L2 1.7 nH Murata LQP03HQ1N7B02D
C1 2.3 pF Murata GRM0335C1H2R3WA01D
C2 1.6 pF Murata GRM0335C1H1R6WA01D
C3 Not Mounted — —
CC1 18 pF Murata GJM0335C1E180GB01D
BRD4186C Reference Manual
RF Section
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