AN11101 BGU7007 GPS front end evaluation board

AN11101
BGU7007 GPS front end evaluation board
Rev. 1 — 7 September 2011
Application note
Document information
Info
Content
Keywords
BGU7007, GPS, FE
Abstract
This document explains the BGU7007 GPS front-end evaluation board
AN11101
NXP Semiconductors
BGU7007 GPS FE EVB
Revision history
Rev
Date
Description
1
Initial document
20110907
Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
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1. Introduction
NXP Semiconductors’ BGU7007 Global Positioning System Front-End Evaluation Board
(BGU7007 GPS FE EVB) is designed to evaluate the performance of the GPS front-end
using:
 NXP Semiconductors’ BGU7007 GPS Low Noise Amplifier;
 A matching inductor;
 A decoupling capacitor
 Two identical GPS band-pass filters
It has a gain of 16.7 dB and a noise figure of 1.7 dB at a current consumption of 4.7mA.
Its superior linearity performance removes interference and noise from co-habitation
cellular transmitters, while retaining sensitivity. The front-end components occupy a total
area of approximately 3 x 3 mm.
In this document, the application diagram, board layout, bill of materials, and typical
results are given, as well as some explanations on GPS related performance parameters
like out-of-band input third-order intercept point O_IIP3, gain compression under jamming
and noise under jamming.
Fig 1.
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BGU7007 GPS front-end evaluation board
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2. General description
Modern cellular phones have multiple radio systems, so problems like co-habitation are
quite common. A GPS receiver implemented in a mobile phone requires the following
factors to be taken into account.
All the different transmit signals that are active in a phone can cause problems like
intermodulation and compression.
Since the GPS receiver needs to receive signals with an average power level of -130
dBm, sensitivity is very important. Currently there are several GPS chipsets on the
market that can be implemented in cell phones, PDAs etc. Although many of these GPS
ICs do have integrated LNA front ends, the noise performance, and as a result the
system sensitivity is not always adequate. The GPS receiver sensitivity is a measure for
how accurate the coordinates are calculated. The GPS signal reception can be improved
by a so called GPS front-end, which improves the sensitivity by filtering out the unwanted
jamming signals and by amplifying the wanted GPS signal with a low-noise amplifier.
The pre-filters and post filters are needed to improve the overall linearity of the system as
well as to avoid overdriving the integrated LNA stage of the GPS receiver.
3. BGU7007 GPS front-end evaluation board
The BGU7007 front-end evaluation board simplifies the RF evaluation of the BGU7007
GPS LNA applied in a GPS front end, that is often used in mobile cell phones. The
evaluation board enables testing of the device RF performance and requires no
additional support circuitry. The board is fully assembled with the BGU7007, including the
input series inductor, decoupling capacitor as well as two SAW filters to optimize the
linearity performance. The board is supplied with two SMA connectors for input and
output connection to RF test equipment. The BGU7007 can operate from a 1.5 V to 2.85
V single supply and consumes about 5 mA.
3.1 Application Circuit
The circuit diagram of the evaluation board is shown in Fig 2. With jumper JU1 the
enable input can be connected either to Vcc or GND.
X3
GND
Ven
Vcc
X4
JU1
C1
5
RF in
X1
SAW
L1
4
3
BGU7007
6
SAW
RF out
X2
1
2
Fig 2.
AN11101
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Circuit diagram of the BGU7007 front-end evaluation board
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3.2 Board Layout
Fig 3.
Printed-Circuit Board layout of the BGU7007 front-end evaluation board
3.3 PCB Layout
A good PCB layout is an essential part of an RF circuit design. The front-end evaluation
board of the BGU7007 can serve as a guideline for laying out a board using the
BGU7007. Use controlled impedance lines for all high frequency inputs and outputs.
Bypass Vcc with decoupling capacitors, preferably 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 of the GND pins is also essential for
good RF performance. Either connect the GND pins directly to the ground plane or
through vias, or do both, which is recommended. The out-of-band rejection of the SAW
filters also depends on the grounding of the filter. The material that has been used for the
evaluation board is FR4 using the stack shown in Fig 4.
20um Cu
0.2mm FR4 Critical
20um Cu
0.8mm FR4 only for
mechanical rigidity of PCB
20um Cu
(1) Material supplier is ISOLA DURAVER; εr = 4.6-4.9: T
Fig 4.
AN11101
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Stack of the PCB material
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4. Bill of materials
Table 1.
BOM of the BGU7007 GPS front-end evaluation board
Designator Description
Footprint
Value
Supplier Name/type
Comment
Ac
LNA MMIC
BGU7007
PCB
1x1.45mm
20x35mm
BGU7007 GPS FE EV Kit
C1
Capacitor
0402
1nF
Murata GRM1555
Decoupling
L1
Inductor
0402
5.6nH
Murata LQW15
Input matching
JK
SAW BPF
1.05x1.35mm
Murata SAFEA1G57KE0F00
[1]
X1, X2
SMA RD
connector
-
Johnson, End launch SMA
RF input/ RF output
X3
DC header
-
-
Molex, PCB header, Right Angle, 1
row, 3 way 90121-0763
Bias connector
X4
JUMPER
-
-
Molex, PCB header, Vertical, 1 row,
3 way 90120-0763
Connect Ven to Vcc
or separate Ven
voltage
-
142-0701-841
Stage
JU1
[1]
JUMPER
Although in this case the Murata SAFEA1G57KE0F00 is used, the performance as given in this document can also be achieved with
the use of GPS SAW filters from other suppliers. See paragraph 4.2
4.1 BGU7007
NXP Semiconductors’ BGU7007 GPS low noise amplifier is designed for the GPS
frequency band. The integrated biasing circuit is temperature stabilized, which keeps the
current constant over temperature. It also enables the superior linearity performance of
the BGU7007. The BGU7007 is also supplied with an enable function that allows it to be
controlled via a logic signal. In disabled mode it only consumes less than1 μA.
The output of the BGU7007 is internally matched for 1575.42 MHz whereas only one
series inductor at the input is needed to achieve the best RF performance. Both the input
and output are AC coupled via an integrated capacitor.
It requires only two external components to build a GPS LNA having the following
advantages:
 Low noise;
 High gain;
 High linearity under jamming;
 Very low package height 0.5 mm;
 Low current consumption;
 Short power settling time
4.2 Band pass filters
The band-pass filters that are implemented in the GPS front-end evaluation board are
key components regarding the overall system linearity and sensitivity. Currently there are
different suppliers on the market that have SAW filters for the GPS band available. One
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BGU7007 GPS FE EVB
of the key performance indicators of these filters is having very high rejection at the
different cell phone TX frequencies, and simultaneously having low insertion loss in the
GPS pass-band. Although the evaluation board is supplied with two Murata
SAFEA1G57KE0F00 the following alternatives can be considered:
1. EPCOS 9444;
2. Murata SAFA1G57KH0F00;
3. Murata SAFA1G57KB0F00 low loss variant;
4. Fujitsu FAR-F6KA-1G5754-L4AA;
5. Fujitsu FAR-F6KA-1G5754-L4AJ;
All these filters can use the same footprint. In order to be able to achieve the rejection
level as indicated in the data sheet of these filters, it is necessary that the filters are
properly grounded. In the layout of the front-end evaluation board the suppliers’
recommendations have been followed. See Fig 5, please note that every GND pin has its
own ground-via and there is a ground path between the input and the output.
Fig 5.
SAW filter footprint
4.3 Series inductor
The evaluation board is supplied with Murata LQW15 series inductor of 5.6nH. This is a
wire wound type of inductor with high quality factor (Q) and low series resistance (Rs).
This type of inductor is recommended in order to achieve the best noise performance.
High Q inductors from other suppliers can be used. If it is decided to use other low cost
inductors with lower Q and higher Rs the noise performance will degrade.
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5. Required Equipment
In order to measure the evaluation board the following is necessary:

DC Power Supply op to 30 mA at 1.5 V to 2.85 V;

Two RF signal generators capable of generating RF signals at the operating
frequency of 1575.42 MHz, as well as the jammer frequencies 1713.42 MHz and
1851.42 MHz;

An RF spectrum analyzer that covers at least the operating frequency of 1575.42
MHz as well as a few of the harmonics. Up to 6 GHz should be sufficient.
“Optional” a version with the capability of measuring noise figure is convenient;

Amp meter to measure the supply current (optional);

A network analyzer for measuring gain, return loss and reverse isolation;

Noise figure analyzer and noise source;

Directional coupler;

Proper RF cables.
6. Connections and setup
The BGU7007 GPS front-end evaluation board is fully assembled and tested. Please
follow the steps below for a step-by-step guide to operate the front-end evaluation board
and testing the device functions.
1. Connect the DC power supply to the Vcc and GND terminals. Set the power supply to
the desired supply voltage, between 1.5 V and 2.85 V, but never exceed 3.1 V as it
might damage the BGU7007.
2. Jumper JU1 is connected between the Vcc terminal of the evaluation board and the
Ven pin of the BGU7007.
3. Connect the RF signal generator and the spectrum analyzer to the RF input and the
RF output of the evaluation board, respectively. Do not turn on the RF output of the
signal generator yet, set it to -40 dBm output power at 1575.42 MHz, set the
spectrum analyzer at 1575.42 MHz center frequency and a reference level of 0 dBm.
4. Turn on the DC power supply and it should read approximately 5mA.
5. Enable the RF output of the generator: The spectrum analyzer displays a tone
around –23 dBm at 1575.42 MHz.
6. Instead of using a signal generator and spectrum analyzer one can also use a
network analyzer in order to measure gain as well as in- and output return loss.
7. For noise figure evaluation, either a noise figure analyzer or a spectrum analyzer with
noise option can be used. The use of a 15 dB noise source, like the Agilent 364B is
recommended. When measuring the noise figure of the evaluation board, any kind of
adaptors, cables etc between the noise source and the evaluation board should be
avoided, since this affects the noise figure.
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Fig 6.
Evaluation board including its connections
7. Linearity
At the average power levels of –130 dBm that have to be received by a GPS receiver,
the system will not have in-band intermodulation problems caused by the GPS-signal
itself. Strong out-of-band cell phone TX jammers however can cause linearity problems,
and result in third-order intermodulation products in the GPS frequency band.
7.1 Out-of-band input third-order intercept point
This parameter is being measured by a two-tone measurement where the carriers have
been chosen as L1+138 MHz and L1+276 MHz. Where L1 is the center of the GPS
band, 1575.42 MHz. So the two carriers are 1713.42 MHz and 1851.42 MHz that can be
seen as two TX jammers in UMTS FDD and GSM1800 cell phone systems.
One third-order product (2f1-f2) generated in the LNA due to amplifier third-order
nonlinearities can fall at the desired 1575.42 MHz frequency as follows:
2f1-f2 = 2(1713.42 MHz)-1851.42 MHz = 1575.42 MHz.
This third-order product can influence the sensitivity of the GPS receiver drastically. So
this third-order intermodulation product needs to be as low as possible, meaning the outof-band intercept point must be as high as possible.
Fig 7 shows the measurement setup used to measure the out-of-band third order
intercept point. Two RF-generators are used to generate the jammers f1 and f2. These
two jammers are combined by an RF combiner. A notch filter is used to prevent inserting
an RF signal at the GPS frequency into the front-end caused by intermodulation of the
two generators and RF combiner combination.
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BGU7007 GPS FE EVB
BGU7007
GPS FE
EVB
X3
GND
Ven
Vcc
X4
JU1
RF-generator 2
RF
combiner
RF-generator 1
GPS
notch
C1
5
RF in
SAW
L1
4
3
BGU7007
1
X1
6
SAW RF out
Spectrum
analyzer
X2
2
Fig 7.
Out-of-band input third order intercept point measurement setup
The input power levels of f1 and f2 that have been used to measure the IM3 levels on the
front-end evaluation board were +10 dBm, shown in Fig 8. Fig 9 shows the IM3 level at
the output of the front-end, measured at VCC = 1.8 V.
With the levels shown in Fig 8 and Fig 9, the out-of-band input third-order intercept point
can be calculated.
As shown in Fig 8 Pin of both f1 and f2 is 10 dBm.
Left-side OIM3 = -79.4 dBm (see Fig 9)
The gain ( G p ) of the front-end is 16.7 dB.
Fig 8.
Input jammers for IM3 measurements
Fig 9.
FE output IM3 level at 1575.42 MHz
The out-of-band output third-order intercept point can be calculated as follows:
O _ OIP3  Pin  f1   G p 
With,
AN11101
Application note
p
2
 p  Pin  f1   Gp  OIM 3
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O _ OIP3  10  16.7 
106.1
 79.8 dBm
2
The out-of-band input third-order intercept point is equal to:
O _ IIP3  O _ OIP3  Gp  79.8  16.7  63.1 dBm
7.2 In-band 1dB gain compression due to 850MHz and 1850MHz jammers
For the measurement described below it is necessary to have clean jammer signals with high RF power in
order to measure these parameters on the actual front-end evaluation board. Since these clean signals are
hard to generate, these measurements are performed on a BGU7007 GPS Low-noise amplifier evaluation
board (user manual available). With the results of these measurements and the typical rejection levels of the
band-pass filters at the jamming frequencies, the values valid for the front-end evaluation board can be
calculated.
As already stated before, signal levels in the GPS frequency band of -130dBm average
will not cause linearity problems in the GPS band itself. This of course is also valid for the
1dB gain compression in-band. The 1dB compression point at 1575.42MHz caused by
cell phone TX jammers however is important.
Measurements have been carried out using the setup shown in Fig 10.
BGU7007
GPS LNA
EVB
X3
GND
Ven
Vcc
X4
Jammer signal
JU1
RF-generator 2
C1
5
RF-generator 1
-20dB
RF in
Directional coupler
L1
4
3
BGU7007
1
X1
6
RF out
Spectrum
analyzer
X2
2
Fig 10. 1dB Gain compression under jamming measurement setup (LNA evaluation board)
The gain was measured between port RFin and RFout of the EVB at the GPS frequency,
while simultaneously a jammer power signal was swept at 20dB attenuated input of the
directional coupler. Please note that the drive power of the jammer is 20dB lower at the
input of the DUT caused by the directional coupler. Fig 11 and Fig 12 show the gain
compression curves with 850MHz and 1850MHz jammers respectively.
Calculating the power level at the front-end gain with 1 dB compression is done as
follows:
At 1 dB gain drop the jammer-generator read out for 850MHz jammer is +5.6 dBm (Vcc =
1.8 V). Taking into account the approx 20 dB attenuation of the directional coupler
Pi1dB= -14.4 dBm (Fig 11). This is for the LNA only. Using the typical rejection of the
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1
SAW filter at 850 MHz which is 44dB the 1dB compression jammer signal level equals:
-14.4 + 44 = 29.6 dBm.
For 1850 MHz jammer the jammer-generator read out at 1 dB gain drop is +10.2 dBm
(Vcc = 1.8 V). Taking into account the approx 20 dB attenuation of the directional coupler
Pi1dB= -9.8 dBm (Fig 12). Again this is for the LNA only. Using the typical rejection of the
2
SAW filter at 1850 MHz which is 46 dB the 1 dB compression jammer signal level
equals:
-9.8 + 46 = 36.2 dBm.
(1) BGU7007 GPS LNA
Vcc = 1.5 V
(measured)
(1) BGU7007 GPS LNA
Vcc = 1.5 V
(measured)
(2) BGU7007 GPS LNA
Vcc = 1.8 V
(measured)
(2) BGU7007 GPS LNA
Vcc = 1.8 V
(measured)
(3) BGU7007 GPS LNA
Vcc = 2.85 V (measured)
(3) BGU7007 GPS LNA
Vcc = 2.85 V (measured)
(4) BGU7007 FE LNA
Vcc = 1.8 V
(4) BGU7007 GPS FE
Vcc = 1.8 V
(calculated)
(Pin 1573 MHz = -45 dBm)
(Pin 1575 MHz = -45 dBm)
Fig 11. Gain versus jammer power at 850 MHz
1.
2.
AN11101
Application note
(calculated)
Fig 12. Gain versus jammer power at 1850 MHz
Rejection at 850MHz from datasheet of Murata SAFEA1G57KE0F00 SAW filter
Rejection at 1850MHz from datasheet of Murata SAFEA1G57KE0F00 SAW filter
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8. Noise figure as function of jammer power at 850MHz
and 1850MHz
For the measurement described below it is necessary to have clean jammer signals with high RF power in
order to measure these parameters on the actual front-end evaluation board. Since these clean signals are
hard to generate, these measurements are performed on a BGU7007 GPS Low-noise amplifier evaluation
board (user manual available). With the results of these measurements and the typical rejection levels of the
band-pass filters at the jamming frequencies, the values valid for the front-end evaluation board can be
calculated.
Noise figure under jamming conditions is a measure of how the LNA behaves when e.g.
a GSM TX interfering signal is at the input of the GPS antenna. To measure this behavior
the setup shown in Fig 13 is used.
The jammer signal is coupled via a directional coupler to the DUT: this is to avoid the
jammer signal damaging the noise source. The GPS BPF is needed to avoid driving the
second-stage LNA in saturation.
BGU7007
GPS LNA
EVB
X3
GND
Ven
Vcc
X4
Jammer signal
JU1
RF-generator
C1
5
Noise
Source
-20dB
RF in
Directional coupler
L1
4
3
BGU7007
6
RF out
1
X1
SAW
2nd stage
LNA
Noise
analyzer
X2
2
Fig 13. Noise under jamming measurement setup (LNA evaluation board)
With the results of these measurements and the specification of the SAW filter, the
jammer power levels that cause noise increase can be calculated.
Calculating the power level at which the front-end noise starts to increase is done as
follows:
As can be seen in Fig 14 with a 850 MHz jammer the LNA starts increasing the noise at
Pjam = -25 dBm. For the front-end the TX rejection of the first BPF needs to be added. For
3
the SAW filter used the rejection at 850 MHz is 44 dB . This means the noise of the frontend will start increasing at an 850 MHz jammer level of Pjam = +19 dBm. For the 1850
MHz jammer the LNA noise starts to increase at Pjam = -30 dBm (see Fig 15). The
4
rejection of the SAW filter at 1850 MHz is 46 dB . This means the noise of the front-end
will start increasing at an 1850 MHz jammer level of Pjam = +16 dBm.
3.
4.
AN11101
Application note
Rejection at 850MHz from datasheet of Murata SAFEA1G57KE0F00 SAW filter
Rejection at 1850MHz from datasheet of Murata SAFEA1G57KE0F00 SAW filter
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(1) BGU7007 GPS LNA
Vcc = 1.5 V
(measured)
(1) BGU7007 GPS LNA
Vcc = 1.5 V
(measured)
(2) BGU7007 GPS LNA
Vcc = 1.8 V
(measured)
(2) BGU7007 GPS LNA
Vcc = 1.8 V
(measured)
(3) BGU7007 GPS LNA
Vcc = 2.85 V (measured)
(3) BGU7007 GPS LNA
Vcc = 2.85 V (measured)
(4) BGU7007 GPS FE
Vcc = 1.8 V
(4) BGU7007 GPS FE
Vcc = 1.8 V
(calculated)
Fig 14. NF at 1575 MHz versus jammer power at 850
MHz.
AN11101
Application note
(calculated)
Fig 15. NF at 1575 MHz versus jammer power at 1850
MHz.
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9. TX rejection levels
When measuring the front-end evaluation board the input level of the network analyzer
has to be on -45 dBm to avoid activating the adaptive biasing. This low input level results
in a very inaccurate measurement result of the TX rejection, which can be seen on the
results pages attached to the evaluation boards.
Fig 16 and Fig 17 show the typical TX rejection levels measured more accurate due to
segmented power calibration.
Fig 16. Typical S-parameter plot at Vcc = 1.8 V
AN11101
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Fig 17. Typical pass band response at Vcc = 1.8 V
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10. Typical front-end evaluation board results
Table 2.
Typical results measured on the evaluation boards
Operating Frequency is f = 1575.42 MHz unless otherwise specified; Temp = 25 °C
Parameter
Symbol
FE EVB FE EVB FE EVB
Unit
Supply Voltage
VCC
1.5
1.8
2.85
V
Supply Current
ICC
4.7
4.7
5.2
mA
Noise Figure
NF
1.7
1.7
1.7
dB
Power Gain
Gp
16.5
16.7
16.9
dB
Input Return Loss
RLin
10.0
10.3
10.7
dB
Output Return Loss
RLout
19.5
20.7
21.0
dB
Reverse Isolation
ISOrev
24.5
24.7
25.3
dB
Input 1dB Gain Compression
Pi1dB
-13.3
-12.3
-11.0
dBm
Output 1dB Gain Compression
Po1dB
2.7
3.7
5.1
dBm
Input 1dB Gain Compression
jammer level at 850MHz
Pi1dB850MHz
29.6
dBm
[2]
Input 1dB Gain Compression
jammer level at 1850MHz
Pi1dB1850MHz
36.2
dBm
[2]
Cell band rejection at 850 MHz
relative to 1575.42 MHz
TX_rej850MHz
>95
dBc
[2]
Cell band rejection at 1850 MHz
relative to 1575.42 MHz
TX_rej1850MHz
>90
dBc
[2]
Input third order intercept point
IIP3
63.1
dBm
[3]
Power settling time
Ton
1.4
1
0.9
µs
Toff
1
0.95
0.9
µs
Remarks
[1]
[1]
The noise figure and gain figures are measured at the SMA connectors of the evaluation board. The losses of the connectors and the
PCB of approximately 0.1dB are not subtracted.
[2]
These parameters are mainly determined by the TX rejection levels of the used BPFs, in this case the Murata SAFEA1G57KE0F00,
but the performance can also be achieved with the use of GPS SAW filters from other suppliers that are on the market.
See paragraph 4.2.
[3]
Out of band IP3, jammers at f1=f+138MHz and f2=f+276MHz, where f=1575.42MHz. Pin(f1)=Pin(f2)=-30dBm
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11. Legal information
11.1 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences
of use of such information.
11.2 Disclaimers
Limited warranty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warranties, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation lost profits, lost savings, business interruption, costs related to the removal
or replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability
towards customer for the products described herein shall be limited in
accordance with the Terms and conditions of commercial sale of NXP
Semiconductors.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liability for inclusion and/or use of
NXP Semiconductors products in such equipment or applications and
therefore such inclusion and/or use is at the customer’s own risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP
AN11101
Application note
Semiconductors accepts no liability for any assistance with applications or
customer product design. It is customer’s sole responsibility to determine
whether the NXP Semiconductors product is suitable and fit for the
customer’s applications and products planned, as well as for the planned
application and use of customer’s third party customer(s). Customers should
provide appropriate design and operating safeguards to minimize the risks
associated with their applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from national authorities.
Evaluation products — This product is provided on an “as is” and “with all
faults” basis for evaluation purposes only. NXP Semiconductors, its affiliates
and their suppliers expressly disclaim all warranties, whether express,
implied or statutory, including but not limited to the implied warranties of noninfringement, merchantability and fitness for a particular purpose. The entire
risk as to the quality, or arising out of the use or performance, of this product
remains with customer.
In no event shall NXP Semiconductors, its affiliates or their suppliers be
liable to customer for any special, indirect, consequential, punitive or
incidental damages (including without limitation damages for loss of
business, business interruption, loss of use, loss of data or information, and
the like) arising out the use of or inability to use the product, whether or not
based on tort (including negligence), strict liability, breach of contract, breach
of warranty or any other theory, even if advised of the possibility of such
damages.
Notwithstanding any damages that customer might incur for any reason
whatsoever (including without limitation, all damages referenced above and
all direct or general damages), the entire liability of NXP Semiconductors, its
affiliates and their suppliers and customer’s exclusive remedy for all of the
foregoing shall be limited to actual damages incurred by customer based on
reasonable reliance up to the greater of the amount actually paid by
customer for the product or five dollars (US$5.00). The foregoing limitations,
exclusions and disclaimers shall apply to the maximum extent permitted by
applicable law, even if any remedy fails of its essential purpose.
11.3 Trademarks
Notice: All referenced brands, product names, service names and
trademarks are property of their respective owners.
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 7 September 2011
© NXP B.V. 2011. All rights reserved.
17 of 20
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BGU7007 GPS FE EVB
12. List of figures
Fig 1.
Fig 2.
Fig 3.
Fig 4.
Fig 5.
Fig 6.
Fig 7.
Fig 8.
Fig 9.
Fig 10.
Fig 11.
Fig 12.
Fig 13.
Fig 14.
Fig 15.
Fig 16.
Fig 17.
BGU7007 GPS front-end evaluation board ....... 3
Circuit diagram of the BGU7007 front-end
evaluation board ............................................... 4
Printed-Circuit Board layout of the BGU7007
front-end evaluation board ................................ 5
Stack of the PCB material ................................. 5
SAW filter footprint ............................................ 7
Evaluation board including its connections ....... 9
Out-of-band input third order intercept point
measurement setup ........................................ 10
Input jammers for IM3 measurements ............ 10
FE output IM3 level at 1575.42 MHz ............... 10
1dB Gain compression under jamming
measurement setup (LNA evaluation board)... 11
Gain versus jammer power at 850 MHz .......... 12
Gain versus jammer power at 1850 MHz ........ 12
Noise under jamming measurement setup (LNA
evaluation board) ............................................ 13
NF at 1575 MHz versus jammer power at 850
MHz. ............................................................... 14
NF at 1575 MHz versus jammer power at 1850
MHz. ............................................................... 14
Typical S-parameter plot at Vcc = 1.8 V.......... 15
Typical pass band response at Vcc = 1.8 V .... 15
AN11101
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 7 September 2011
© NXP B.V. 2011. All rights reserved.
18 of 20
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BGU7007 GPS FE EVB
13. List of tables
Table 1.
Table 2.
BOM of the BGU7007 GPS front-end evaluation
board ................................................................. 6
Typical results measured on the evaluation
boards ............................................................. 16
AN11101
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 7 September 2011
© NXP B.V. 2011. All rights reserved.
19 of 20
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NXP Semiconductors
BGU7007 GPS FE EVB
14. Contents
1.
2.
3.
3.1
3.2
3.3
4.
4.1
4.2
4.3
5.
6.
7.
7.1
7.2
8.
9.
10.
11.
11.1
11.2
11.3
12.
13.
14.
Introduction ......................................................... 3
General description ............................................. 4
BGU7007 GPS front-end evaluation board........ 4
Application Circuit .............................................. 4
Board Layout ...................................................... 5
PCB Layout ........................................................ 5
Bill of materials.................................................... 6
BGU7007 ........................................................... 6
Band pass filters................................................. 6
Series inductor ................................................... 7
Required Equipment ........................................... 8
Connections and setup ....................................... 8
Linearity ............................................................... 9
Out-of-band input third-order intercept point ...... 9
In-band 1dB gain compression due to 850MHz
and 1850MHz jammers .................................... 11
Noise figure as function of jammer power at
850MHz and 1850MHz ....................................... 13
TX rejection levels ............................................. 15
Typical front-end evaluation board results ..... 16
Legal information .............................................. 17
Definitions ........................................................ 17
Disclaimers....................................................... 17
Trademarks ...................................................... 17
List of figures..................................................... 18
List of tables ...................................................... 19
Contents ............................................................. 20
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in the section 'Legal information'.
© NXP B.V. 2011.
All rights reserved.
For more information, visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
Date of release: 7 September 2011
Document identifier: AN11101