Table 4.1. Bill of Materials for the BRD4250A 915 MHz 19.5 dBm RF Matching Network

Component name

Value

Manufacturer

Part Number

BAL1

Balun

Johanson Technology

0900BL15C050

C3

1.8 pF

Murata

GRM1555C1H1R8WA01

C4

1.8 pF

Murata

GRM1555C1H1R8WA01

C5

3.9 pF

Murata

GRM1555C1H3R9WA01

C6

3.3 pF

Murata

GRM1555C1H3R3BA01

C7

5.6 pF

Murata

GRM1555C1H5R6BA01

C8

3.3 pF

Murata

GRM1555C1H3R3BA01

C10

56 pF

Murata

GRM1555C1H560GA01

L3

3.3 nH

Murata

LQW15AN3N3B80

L4

3.3 nH

Murata

LQW15AN3N3B80

L5

18 nH

Murata

LQW15AN18NG00

L6

10 nH

Murata

LQW15AN10NJ00

L7

10 nH

Murata

LQW15AN10NJ00

4.5 Bill of Materials for the 2.4 GHz Matching

The Bill of Materials of the 2.4 GHz matching network of the BRD4250A Radio Board is shown in the following table.

Table 4.2. Bill of Materials for the BRD4250A 2.4 GHz 19.5 dBm RF Matching Network

Component name

Value

Manufacturer

Part Number

C1

2.0 pF

Murata

GRM1555C1H2R0WA01

C2

1.0 pF

Murata

GRM1555C1H1R0WA01

L1

1.8 nH

Murata

LQP15MN1N8W02

L2

3.0 nH

Murata

LQP15MN3N0W02

4.6 Inverted-F Antenna

The BRD4250A 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 thus

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 better than

-10 dB) for the entire 2.4 GHz band.

BRD4250A Reference Manual

RF Section

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