Application Notes

AN11749
BGS8M4UK LTE LNA with bypass switch evaluation board
Rev. 1 — 17 November 2015
Application note
Document information
Info
Content
Keywords
BGS8M4UK, LTE, LNA
Abstract
This document explains the BGS8M4UK LTE LNA evaluation board
Ordering info
Board-number: OM17019
12NC: 9340 699 49598
Contact information
For more information, please visit: http://www.nxp.com
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Revision history
Rev
Date
Description
1
First publication
20151117
Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
2 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
1. Introduction
NXP Semiconductors’ BGS8M4UK LTE LNA Evaluation Board is designed to evaluate
the performance of the LTE LNA in its typical application, using:

NXP Semiconductors’ BGS8M4UK LTE Low Noise Amplifier

A matching inductor

A decoupling capacitor
NXP Semiconductors’ BGS8M4UK is a low-noise amplifier with bypass switch for LTE
receiver applications in an extremely small Wafer-Level Chip-Scale Package (WLCSP),
0.69 mm x 0.44 mm x 0.29 mm; 6 solder bumps (0.25 mm / 0.26 mm bump pitch). The
BGS8M4UK features gain of 16.6 dB and a noise figure of 0.8 dB at a current
consumption of 4.4 mA. The Bypass switch insertion loss is 2.7 dB. Its superior linearity
performance removes interference and noise from co-habitation cellular transmitters,
while retaining sensitivity. The LNA components occupy a total area of approximately 1.3
mm2.
In this document, the application diagram, board layout, bill of materials, and typical
performance are given, as well as some explanations on LTE related RF-parameters like
input third-order intercept point IIP3, gain compression and noise.
Fig 1.
AN11749
Application note
BGS8x4UK LNA evaluation board (used for BGS8L4UK, BGS8M4UK)
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
3 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
2. General description of application & product
Modern cellular phones have multiple radio systems, so problems like co-habitation are
quite common. Since the LTE diversity antenna needs to be placed far from the main
antenna to ensure the efficiency of the channel, a low noise amplifier close to the
antenna is used to compensate the track-losses (and SAW-filter losses when applicable)
on the printed circuit board. A LTE receiver implemented in a mobile phone requires a
low current consumption and low Noise Figure. All the different transmit signals that are
active in smart phones and tablets can cause problems like inter-modulation and
compression. Therefore also a high linearity is required.
2.1 BGS8x4: Advantage of integrated By-pass function
The major advantage of having a bypass-switch option is the very low current
consumption (<1µA) when LTE LNA is not needed in the receive chain (at high RSSI/CQI
level, 3~5dB higher than the Sensitivity level). Fig 2 gives a graphical explanation of this
advantage.
LNA mode setting versus received signal level:
LNA Gain
Gain mode:
Sensitivity enhancement
Icc=5-5.5mA
LNA Gain
By-pass control
hysteresis
Sensitivity level
Received signal strength indicator (RSSI)
Higher RSSI
Lower RSSI
Fig 2.
By-pass mode:
No gain needed
Icc < 1 uA
LNA mode setting versus received signal level
To avoid frequently switching between Gain- and bypass-mode around chosen Receiver
Signal Strength Indicator (RSSI) switching level, one should take a Hysteresis Loop into
consideration in the switching logic of the control chip (transceiver or baseband chip),
see Fig 2.
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
4 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
3. BGS8M4UK LTE LNA evaluation board
The BGS8M4UK LNA evaluation board simplifies the RF evaluation of the BGS8M4UK
LTE LNA applied in a LTE front-end, 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 BGS8M4UK including the input series
inductor and decoupling capacitor. The board is supplied with two SMA connectors for
input and output connection to RF test equipment. The BGS8M4UK can operate from a
1.5 V to 3.1 V single supply and consumes typical 4.4 mA.
3.1 Application Circuit
The circuit diagram of the evaluation board is shown in Fig 3. With jumper JU1 the
control input can be connected either to Vcc (Gain-mode) or GND (Bypass mode).
BGS8x4UK
LTE LNA EVB
BGS8x4UK
Fig 3.
AN11749
Application note
Circuit diagram of the BGS8x4UK LNA evaluation board (used for BGS8L4UK,
BGS8M4UK)
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
5 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
3.2 PCB Layout
Fig 4.
Printed-Circuit Board layout of the BGS8x4UK LNA evaluation board (used for
BGS8L4UK, BGS8M4UK)
A good PCB layout is an essential part of an RF circuit design. The LNA evaluation board
of the BGS8M4UK can serve as a guideline for laying out a board using the BGS8M4UK.

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 material that has been used for the evaluation board is FR4 using the stack shown in
Fig 5.
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 5.
AN11749
Application note
Stack of the PCB material
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
6 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
3.3 Bill of materials
Table 1.
BOM of the BGS8M4UK LTE LNA evaluation board
Designator Description Footprint
Value
Supplier Name/type
Comment
-
WLCSP
BGS8M4UK
0.69 mm x 0.44
mm x 0.2 mm,
NXP
6 solder bumps
(0.252 mm / 0.260
mm bump pitch)
PCB
20 x 35mm
BGS8M4UK LTE LNA EV Kit
C1
Capacitor
0402
1µF
Murata GRM1555
Decoupling
L1
Inductor
0402
4.7nH
Murata LQW15
Input matching
X1, X2
SMA RD
connector
-
-
Johnson, End launch SMA
RF input/ RF output
X3
DC header
-
-
Molex, PCB header, Right Angle, 1 Bias connector
row, 3 way 90121-0763
X4
JUMPER
-
-
Molex, PCB header, Vertical, 1
row, 3 way 90120-0763
142-0701-841
Stage
JU1
Connect Ven to Vcc
or separate Ven
voltage
JUMPER
3.4 BGS8M4UK
NXP Semiconductors’ BGS8M4UK LTE low noise amplifier is designed for the LTE low
band. The integrated biasing circuit is temperature stabilized, which keeps the current
constant over temperature. It also enables the superior linearity performance of the
BGS8M4UK. The BGS8M4UK is also equipped with an enable function that allows it to
be controlled via a logic signal. In disabled mode it consumes less than1 μA.
The output of the BGS8M4UK is internally matched between 1805 MHz and 2200 MHz,
whereas only one series inductor at the input is needed to achieve the best RF
performance. The input and output are AC coupled via an integrated capacitor.
It requires only two external components to build a LTE LNA having the following
advantages:
AN11749
Application note

Low noise

System optimized gain

High linearity under jamming

0.69 mm x 0.44 mm x 0.29 mm; 6 solder bumps (0.25 mm / 0.26 mm bump
pitch). WLCSP.

Low current consumption

Short power settling time
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
7 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
3.5 Series inductor
The evaluation board is supplied with Murata LQW15 series inductor of 4.7 nH. This is a
wire wound type of inductor with high quality factor (Q) and low series resistance (Rs)
like the Murata LQW15A series (see Table 2). 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.
Table 2.
Type
Series Inductor options
Murata
Multilayer
Size
Size
Size
0201
0402
0603
LQG
Non-Magnetic Core
Film
Wirewound
Non-Magnetic Core
AN11749
Application note
LQP
LQW
15H
18H
NF↑↑
NF↑
03T
15M
NF↑↑
NF↑
15A
18A
Default
NF↓
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
Comment
Lowest NF
© NXP B.V. 2015. All rights reserved.
8 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
4. Typical LNA evaluation board results
4.1 S-Parameters
The measured S-Parameters and stability factor K are given in the figures below. For the
measurements, a BGS8M4UK-LNA EVB is used ((see Fig 21). Measurements have
been carried out using the setup shown in Fig 22.
Rollet Stability Factor
Small Signal Gain
1000
30
20
100
0
-10
Gain-mode
-20
K-Factor
S21 [dB]
10
Gain-mode
Bypass-mode
Bypass-mode
-30
10
1
-40
-50
0.1
0
2
4
6
Frequency [GHz]
8
10
0
8
10
0
-5
-5
-10
-10
-15
-20
Gain-mode
-25
Bypass-mode
S22 [dB]
S11 [dB]
4
6
Frequency [GHz]
Output Reflection Coefficient
Input Reflection Coefficient
0
-15
-20
Gain-mode
-25
Bypass-mode
-30
-30
-35
-35
0
Fig 6.
2
2
4
6
Frequency [GHz]
8
10
0
2
4
6
Frequency [GHz]
8
10
BGS8M4UK S-Parameters (typical values). Vcc=2.8V, Pin=-30dBm. Gain mode and Bypass mode
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
9 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
S21 [dB]
Small Signal Gain
20
18
16
14
12
10
8
6
4
2
0
-2
-4
Gain-mode
Bypass-mode
1.8 1.9 1.9 2.0 2.0 2.1 2.1 2.2 2.2
Frequency [GHz]
Output Reflection Coefficient
0
-5
-10
Gain-mode
Bypass-mode
-15
-20
Gain-mode
-25
Bypass-mode
-30
-35
1.8 1.9 1.9 2.0 2.0 2.1 2.1 2.2 2.2
Frequency [GHz]
Fig 7.
S22 [dB]
S11 [dB]
Input Reflection Coefficient
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
1.8 1.9 1.9 2.0 2.0 2.1 2.1 2.2 2.2
Frequency [GHz]
BGS8M4UK S-Parameters (typical values). Vcc=2.8V, Pin=-30dBm, Gain mode and Bypass mode
(Frequency range zoomed in).
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
10 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
4.2 Improving the Gain by optimized matching
The design of the BGS8x4UK LNA’s are optimized for best RF-performance using
only one input matching coil. In some cases, the Gain can be increased if more inand output components are used. Fig 8 gives the theoretical maximum gain (Gmax)
using (ideal) optimized in- and output matching circuits, and S21 (typical measured
performance) of a BGS8M4UK demoboard.
BGS8M4UK_110518#1, Vcc=2.8V, Gain Mode
25
20
Gain [dB]
15
10
Gmax
S21
5
0
-5
0.0E+00
freq [Hz]
1840
1960
2140
Fig 8.
AN11749
Application note
5.0E+08
1.0E+09
Gmax(dB)
18.9
18.3
17.5
1.5E+09
Freq [Hz]
S21 (dB)
17.2
16.8
15.9
2.0E+09
S11 (dB)
-6.1
-7.6
-9.5
2.5E+09
3.0E+09
S22 (dB)
-19.2
-13.3
-9.4
S12(dB)
-28.4
-27.4
-26.5
S21 and Maximum achievable gain (Gmax) typ. values (Gain mode)
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
11 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Fig 9 and Fig 10 give an implementation of an improved matching circuit using 3
inductors to increase the Gain.
Fig 9.
Circuit diagram of the BGS8x4UK LNA evaluation board using 2 input and one
output inductor to optimize the Gain.
L2
L1
L3
Fig 10. EVB detail of the BGS8x4UK LNA evaluation board using 2 input and one output
inductor to optimize the Gain.
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
12 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
4.3 1dB gain compression
Strong in-band cell phone TX jammers can cause linearity problems and result in thirdorder intermodulation products in the LTE frequency band. In this chapter the effects of
these strong signals is shown. For the measurements, a BGS8M4UK-LNA EVB is used
((see Fig 21). Measurements have been carried out using the setup shown in Fig 22. The
gain as function of input power of the DUT was measured between port RFin and RFout
of the EVB at the low LTE center frequencies. The figures below show the gain
compression curves at LNA-board.
Icc vs Input Power, f=1843MHz
Gain vs Input Power, f=1843MHz
20
18
16
14
15
12
Vcc=1.5V
10
Vcc=1.8V
Gain [dB]
Icc [mA]
10
Vcc=2.8V
Vcc=1.5V
6
Vcc=1.8V
4
Vcc=2.8V
2
Vcc=3.1V
5
8
Vcc=3.1V
0
-2
-4
0
-6
-30
-25
-20
-15
-10
Pin [dBm]
-5
0
5
-30
Fig 11. Icc versus input power , f=1843MHz (band 3)
-25
-20
-15
-10
Pin [dBm]
-5
0
5
Fig 12. Gain versus input power , f=1843 (band 3)
Icc vs Input Power, f=1960MHz
Gain vs Input Power, f=1960MHz
20
18
16
14
15
12
Vcc=1.5V
10
Vcc=1.8V
Vcc=2.8V
Vcc=3.1V
5
Gain [dB]
Icc [mA]
10
8
Vcc=1.5V
6
Vcc=1.8V
4
Vcc=2.8V
2
Vcc=3.1V
0
-2
-4
0
-6
-30
-25
-20
-15
-10
Pin [dBm]
-5
0
5
Fig 13. Icc versus input power , f=1960MHz (band 2)
AN11749
Application note
-30
-25
-20
-15
-10
Pin [dBm]
-5
0
5
Fig 14. Gain versus input power , f=1960MHz (band 2)
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
13 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Gain vs Input Power, f=2140MHz
Icc vs Input Power, f=2140MHz
18
20
16
14
12
15
Gain [dB]
Icc [mA]
10
Vcc=1.5V
10
Vcc=1.8V
Vcc=2.8V
Vcc=1.5V
6
Vcc=1.8V
4
Vcc=2.8V
2
Vcc=3.1V
5
8
Vcc=3.1V
0
-2
-4
-6
0
-30
-25
-20
-15
-10
Pin [dBm]
-5
0
-30
5
Fig 15. Icc versus input power , f=2140MHz (band 1)
-25
-20
-15
-10
Pin [dBm]
-5
0
5
Fig 16. Gain versus input power , f=2140MHz (band 1)
4.4 IIP3 2-Tone Test
The figures below show measured input-IP3-results of the DUT measured with a 2-Tone
test at the LTE-bands. For the measurements, a BGS8M4UK-LNA EVB is used (see Fig
21). Measurements have been carried out using the setup shown in Fig 22.
Input Power @ Intercept Point of the 3rd Order
-1.0
-1.5
-2.0
IIP3 [dBm]
-2.5
f=1838MHz (band 3)
-3.0
f=1955MHz (band 2)
-3.5
f=2135MHz (band 1)
-4.0
-4.5
-5.0
1.0
1.5
2.0
2.5
3.0
3.5
Vcc [V]
Fig 17. IIP3=F(Vcc), Pin=-30dBm
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
14 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
4.5 Enable Timing Test
The following diagram shows the setup to test LNA Turn ON and Turn OFF time.
Set the waveform generator to square mode and the output amplitude at 3Vrms with
high output impedance. The waveform generator has adequate output current to drive
the LNA therefore no extra DC power supply is required which simplifies the test
setup.
Set the RF signal generator output level to -20dBm at a frequency between 1805 MHz
and 2200 MHz and increase its level until the output DC on the oscilloscope is at 5mV
on 1mV/division, the signal generator RF output level is approximately -3dBm.
It is very important to keep the cables as short as possible at input and output of the
LNA so the propagation delay difference on cables between the two channels is
minimized.
It is also critical to set the oscilloscope input impedance to 50ohm on channel 2 so the
diode detector can discharge quickly to avoid a false result on the Turn OFF time
testing.
WAVEFORM
GENERATOR
POWER
SUPPLY
BGS8x2
LTE LNA
EVB
X3
GND CTRL
OSCILLOSCOPE
Vcc
X4
ch1: 1M? INPUT Z
JU1
C1
6
RF in
RF GENERATOR
X1
2
L1
5
BGS8x2
Vout
RF out
3
4
ch2: 50? INPUT Z
X2
1
SCHOTTKY
DETECTOR
(AGILENT 8473B )
Fig 18. Setup Enable Timing Test
Fig 19 and Fig 20 show the measured Ton and T_bypass test.
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
15 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Fig 19. Results Enable Timing Test. Frq=1960MHz, Pin=-20dBm, Vcc=2.8V : Ton~600 ns.
Fig 20. Results Enable Timing Test. Frq=1960MHz, Pin=-20dBm, Vcc=2.8V : T_Bypass~140 ns.
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
16 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
5. Required Measurement Equipment
In order to measure the evaluation board the following is necessary:

DC Power Supply up to 30 mA at 1.5 V to 3.1 V

Two RF signal generators capable of generating RF signals at the LTE operating
frequencies between 1805 MHz and 2200 MHz.

An RF spectrum analyzer that covers at least the LTE operating frequencies of
1805 MHz to 2200 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 BGS8M4UK LTE LNA evaluation board is fully assembled and tested (see Fig 21).
Please follow the steps below for a step-by-step guide to operate the LNA 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 3.1 V, but never exceed 3.1 V as it
might damage the BGS8M4UK.
2. Jumper JU1 is connected between the Vcc terminal of the evaluation board and the
Ven pin of the BGS8M4UK.
3. Connect the RF signal generator and the spectrum analyzer to the RF input and the
RF output of the evaluation board, respectively (Fig 21). Do not turn on the RF output
of the signal generator yet, set it to approximately -30 dBm output power at center
frequency of the wanted LTE-band and set the spectrum analyzer at the same center
frequency and a reference level of 0 dBm.
4. Turn on the DC power supply and it should read approximately 5 mA.
5. Enable the RF output of the generator: The spectrum analyzer displays a tone
around –15 dBm.
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, P1dB
and IP3 (see Fig 22).
7. For noise figure evaluation, either a noise figure analyzer or a spectrum analyzer with
noise option can be used. The use of a 5 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
minimized, since this affects the noise figure (see Fig 23).
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
17 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Fig 21. Evaluation board including its connections
Fig 22. 2-Tone Setup for 50Ω LNA board tests (S-Parameters, P1dB and 2-Tone-tests)
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
18 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
Fig 23. Setup diagram for 50Ω LNA-board NF-Measurements.
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
19 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
7. Legal information
7.1 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.
7.2 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. NXP Semiconductors takes no
responsibility for the content in this document if provided by an information
source outside of NXP Semiconductors.
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 and its suppliers accept 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.
AN11749
Application note
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP
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.
7.3 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 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
20 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
8. List of figures
Fig 1.
BGS8x4UK LNA evaluation board (used for
BGS8L4UK, BGS8M4UK) ................................. 3
Fig 2.
LNA mode setting versus received signal level . 4
Fig 3.
Circuit diagram of the BGS8x4UK LNA
evaluation board (used for BGS8L4UK,
BGS8M4UK) ..................................................... 5
Fig 4.
Printed-Circuit Board layout of the BGS8x4UK
LNA evaluation board (used for BGS8L4UK,
BGS8M4UK) ..................................................... 6
Fig 5.
Stack of the PCB material ................................. 6
Fig 6.
BGS8M4UK S-Parameters (typical values).
Vcc=2.8V, Pin=-30dBm. Gain mode and Bypass
mode ................................................................. 9
Fig 7.
BGS8M4UK S-Parameters (typical values).
Vcc=2.8V, Pin=-30dBm, Gain mode and Bypass
mode ............................................................... 10
(Frequency range zoomed in). .......................................... 10
Fig 8.
S21 and Maximum achievable gain (Gmax) typ.
values (Gain mode)......................................... 11
Fig 9.
Circuit diagram of the BGS8x4UK LNA
evaluation board using 2 input and one output
inductor to optimize the Gain. ......................... 12
Fig 10.
EVB detail of the BGS8x4UK LNA evaluation
board using 2 input and one output inductor to
optimize the Gain. ........................................... 12
Fig 11.
Icc versus input power , f=1843MHz (band 3) . 13
Fig 12.
Gain versus input power , f=1843 (band 3) ..... 13
Fig 13.
Icc versus input power , f=1960MHz (band 2) . 13
Fig 14.
Gain versus input power , f=1960MHz (band 2)
........................................................................ 13
Fig 15.
Icc versus input power , f=2140MHz (band 1) . 14
Fig 16.
Gain versus input power , f=2140MHz (band 1)
........................................................................ 14
Fig 17.
IIP3=F(Vcc), Pin=-30dBm ............................... 14
Fig 18.
Setup Enable Timing Test ............................... 15
Fig 19.
Results Enable Timing Test. Frq=1960MHz,
Pin=-20dBm, Vcc=2.8V : Ton~600 ns. ............ 16
Fig 20.
Results Enable Timing Test. Frq=1960MHz,
Pin=-20dBm, Vcc=2.8V : T_Bypass~140 ns. .. 16
Fig 21.
Evaluation board including its connections ..... 18
Fig 22.
2-Tone Setup for 50Ω LNA board tests (SParameters, P1dB and 2-Tone-tests) ............. 18
Fig 23.
Setup diagram for 50Ω LNA-board NFMeasurements. ............................................... 19
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
21 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
9. List of tables
Table 1.
Table 2.
BOM of the BGS8M4UK LTE LNA evaluation
board ................................................................. 7
Series Inductor options ..................................... 8
AN11749
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 17 November 2015
© NXP B.V. 2015. All rights reserved.
22 of 23
AN11749
NXP Semiconductors
BGS8M4UK LTE LNA EVB
10. Contents
1.
2.
2.1
3.
3.1
3.2
3.3
3.4
3.5
4.
4.1
4.2
4.3
4.4
4.5
5.
6.
7.
7.1
7.2
7.3
8.
9.
10.
Introduction ......................................................... 3
General description of application & product... 4
BGS8x4: Advantage of integrated By-pass
function .............................................................. 4
BGS8M4UK LTE LNA evaluation board ............. 5
Application Circuit .............................................. 5
PCB Layout ........................................................ 6
Bill of materials ................................................... 7
BGS8M4UK........................................................ 7
Series inductor ................................................... 8
Typical LNA evaluation board results ............... 9
S-Parameters ..................................................... 9
Improving the Gain by optimized matching ...... 11
1dB gain compression ...................................... 13
IIP3 2-Tone Test .............................................. 14
Enable Timing Test .......................................... 15
Required Measurement Equipment ................. 17
Connections and setup ..................................... 17
Legal information .............................................. 20
Definitions ........................................................ 20
Disclaimers....................................................... 20
Trademarks ...................................................... 20
List of figures..................................................... 21
List of tables ...................................................... 22
Contents ............................................................. 23
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. 2015.
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: 17 November 2015
Document identifier: AN11749
Similar pages