Silicon Laboratories BRD4257B, Reference Manual

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Table 4.1. Bill of Materials for the BRD4257B Sub-GHz RF Matching Network
Component Name Value Manufacturer Part Number
L3 3.3 nH Murata LQW15AN3N3B80D
L4 3.3 nH Murata LQW15AN3N3B80D
L5 18 nH Murata LQW15AN18NJ00D
L6 11 nH Murata LQW15AN11NG00D
L7 11 nH Murata LQW15AN11NG00D
C3 1.9 pF Murata GRM1555C1H1R9WA01D
C4 1.9 pF Murata GRM1555C1H1R9WA01D
C5 3.9 pF Murata GRM1555C1H3R9WA01D
C6 3.0 pF Murata GRM1555C1H3R0CA01D
C7 5.6 pF Murata GRM1555C1H5R6BA01D
C8 3.0 pF Murata GRM1555C1H3R0CA01D
C10 56 pF Murata GRM1555C1H560GA01D
4.5 Bill of Materials for the 2.4 GHz Matching
The Bill of Materials of the 2.4 GHz matching network of the BRD4257B Radio Board is shown in the following table.
Table 4.2. Bill of Materials for the BRD4257B 2.4GHz RF Matching Network
Component Name Value Manufacturer Part Number
L1 1.8 nH Murata LQP15MN1N8W02D
L2 3.0 nH Murata LQP15MN3N0W02D
C1 2.0 pF Murata GRM1555C1H2R0WA01D
C2 1.0 pF Murata GRM1555C1H1R0WA01D
4.6 Inverted-F Antenna
The BRD4257B Radio Board includes an on-board printed inverted-F antenna tuned for the 2.4 GHz band. Due to the design restric-
tions of the Radio Board, the input of the antenna and the output of the matching network can't be placed directly next to each other.
Therefore, a 50 Ohm transmission line was necessary to connect them. The resulting impedance and reflection measured at the output
of the matcing network are shown in the following figure. As it can be observed, the impedance is close to 50 Ohm (the reflection is
around or better than -10 dB) for the entire 2.4 GHz band.
BRD4257B Reference Manual
RF Section
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