AN11102 PHILIPS [NXP Semiconductors], AN11102 Datasheet - Page 6

• Manufacturer Part Number: AN11102
• Description: BFU725F/N1 2.4 GHz LNA evaluation board
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
Table 4.
AN11102
Application note
Designator Description
C1
C2
C3,C6
C4,C5
L1
L3
R1
R2
R3
R4
R5
R6
X1,X2
X3
Bill of Materials
Capacitor
Capacitor
Capacitor
Capacitor
Inductor
Inductor
Resistor
Resistor
Resistor
Resistor
Resistor
Resistor
SMA RF
connector
DC header
3.3 PCB Layout
3.4 Bill of Materials
A good PCB Layout is an essential part of an RF circuit design. The EVB of the
BFU725F/N1 can serve as a guideline for laying out a board using either the
BFU725F/N1. Use controlled impedance lines for all high frequency inputs and outputs.
Bypass VCC with decoupling capacitors, preferable located as close as possible to the
device. For long bias lines it may be necessary to add decoupling capacitors along the
line further away from the device. Proper grounding the emitters is also essential for the
performance. Either connect the emitters directly to the ground plane or through vias, or
do both.
The material that has been used for the EVB is FR4 using the stack shown in Fig 4.
Fig 4.
35um Cu
35um Cu
35um Cu
(1) Material supplier is ISOLA DURVAVER;
Footprint
0402
0402
0402
0402
0402
0402
0402
0402
0402
0402
0402
0402
-
-
Stack of PCB material
All information provided in this document is subject to legal disclaimers.
Value
15pF
2.7pF
1.5pF
100nF
12nH
0
51 k
100
0
33
27
5.6nH
Rev. 1 — 28 July 2011
Supplier Name/type
MurataGRM1555
MurataGRM1555
MurataGRM1555
MurataGRM1555
Murata/LQW15A High Q low Rs
Murata/LQG15HS
Various
Various
Various
Various
Various
Various
Johnson, End launch SMA 142-0701-
841
Molex, PCB header, Right Angle, 1 row,
3 way 90121-0763
ε
r=4.6-4.9: T
0.2mm FR4 Critical
0.8mm FR4 only for
mechanical rigidity of PCB
BFU725F/N1_2.4GHz LNA EVB
Comment
DC blocking *
DC blocking *
LF Decoupling
LF Decoupling
(optional)
Input matching
Input matching
Not used
Bias setting
Bias setting
Not Used
Output matching
Output matching
RF input/ RF output
Bias connector
AN11102
© NXP B.V. 2011. All rights reserved.
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