BGA7351,115 NXP Semiconductors, BGA7351,115 Datasheet - Page 2

• Manufacturer Part Number: BGA7351,115
• Description: Specifications: Type: Variable Gain Amplifier ; Applications: Wireless ; Package / Case: 32-VFQFN Exposed Pad ; Packaging: Tape & Reel (TR) ; Lead Free Status: Lead Free ; RoHS Status: RoHS Compliant
• Manufacturer: NXP Semiconductors

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High Performance RF for
wireless infrastructure
Looking for a partner who can help you meet the challenges of wireless infrastructure base station
design? As a global leader in RF technology and component design, NXP Semiconductors offers
a complete portfolio of RF products, from low- to high-power signal conditioning and high-speed
data converters that deliver advanced performance and help simplify your design and development
process. Our solutions range from discrete devices to modular building blocks, so you can design a
highly efficient signal chain.
NXP is focused on component innovation, and on architectural breakthroughs for base station RF
boards. One example is the further digitization of the transmission chain, bringing digital signals
closer to the antenna. Another is a digital signals transmitter that achieves very high efficiency by
using a switch mode power amplifier (SMPA) and is software reconfigurable for multiple frequency
bands.
A power stronghold
NXP has built a strong position in RF transistors for base station power amplifiers with reliable and innovative solutions. These
include our Si-based LDMOS technology, which offers best in-class efficiency, power, and ruggedness, and our new, high-speed
technology using gallium nitride (GaN) material.
Optimized for Doherty applications, our 8
operators increase base station efficiency. The combination of the single transistor performance with our latest achievements
in 2- and 3-way Doherty amplifier designs saves network operating costs as well as CO
efficiencies to ever higher levels, paving the way towards Green Mobile Communication Infrastructures.
Small signal, big choice
Choose the best-fit solution for your application from our extensive portfolio of small signal RF components including low noise
amplifiers (LNAs), medium power amplifiers, variable gain amplifiers (VGAs), mixers, local oscillators (LOs), and up and down
conversion ICs.
Our portfolio is based on high performance, state-of-the-art silicon based technologies such as our QUBiC4 BiCMOS process.
QUBiC4 components meet the performance requirements (noise figure, linearity, power efficiency) of RF base stations and allow
a higher level of integration, compared to traditional gallium arsenide (GaAs) components.
An optimized standard for RF High Speed Data converters
As a leader in high performance mixed-signal IC products, NXP offers an extensive selection of high-speed data converters, with
digital interfaces including JESD204A (in the CGV product line), as well as CMOS LVCMOS and LVDS DDR interfaces.
NXP’s high-speed DACs and ADCs deliver best-in-class converter core performance and ultra-stable dynamic performance
across a broad temperature range. NXP is the only semiconductor vendor to offer high speed data converters, small-signal RF
building blocks and RF power amplifiers, to enable system-level integration across the full radio transceiver signal chain.
th
generation LDMOS delivers unprecedented performance, helping wireless network
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emissions. Our products push amplifier
Base station application diagram
The block diagram above shows base station transmit (upper part, Tx) and receive (lower part, Rx) functions, and includes the Tx feedback
function (middle part, Tx feedback).
The signals generated in the “Digital Baseband & Control” block follow the air interface standard requirements. These signals
are interfaced to the DAC via serial interface SER. The SER can use the LVDS or JEDEC standard. After the signals are fed to
the I-DAC and Q-DAC, they are converted to the analog domain. Before the I and Q signals enter the IQ modulator, they are
first low-pass filtered to remove any aliasing signals. At the IQ modulator, the signals are up-converted to RF using an LO signal
coming from the PLL/VCO device, typically called the LO generator. Due to device aging and variation in cell load, the
up-converted signals are fed to the VGA to control the power level. An additional band pass filter is needed to remove the
out-of-band spurs. The clean signal is fed to the RF power board, where the desired transmit power is made. Finally, the
RF power signal is fed to the antenna via a duplexer.
Directly after the final stage amplifier, a signal coupler picks up a certain amount of the RF signal, which is attenuated and then
down-mixed using the IF Mixer. This signal is called the observation signal, and is used to derive coefficients for the digital
pre-distortion algorithm. Since power levels vary, the observation is first fed to the VGA to control the power level, and after
band pass filtering, the signal is converted to the digital domain using an ADC. The same serial interface is used to send the
digital signals to the baseband processor.
At the receiver, the received signal directly after the duplexer is fed to the LNA for direct amplification, since the received signal
level is quite low. If the first LNA is mounted in the tower top, a long RF cable is used to interface the RF signals with a base
transceiver station (BTS). A second LNA is used to amplify the received signals. Band pass filtering is applied to reduce the
out-of-band signal levels before these signals are applied to the IF mixer. Signal levels that change dramatically require a VGA to
maintain the full scale ranges of the I-ADC and Q-ADC for optimal conversion performance. Low pass filtering is used before the
ADC to remove the aliasing signals. These digital signals are interfaced to the baseband using a serial interface such as JEDEC.
The sample clocks and LO signals are derived from clock cleaners and PLLs respectively. This is denoted as Clock and PLL / VCO
in the block diagram. This set-up is required to make a synchronized system. Typically denoted in SNRs, and in order to improve
reception quality, the receive function is equipped with a second receiver, called a diversity receiver.
SER Q-DAC
SER I-DAC
SER ADC
SER ADC
SER ADC
µC
PLL
PLL
PROCESSING
BPF
LPF
LPF
LPF
LPF
VGA
VGA
VCO
VGA
VCO
PLL
PLL
DATACONVERTERS
I/Q-MOD
IF mixer
mixer
mixer
mixer
0
IF mixer
IF mixer
X
X
X
90
X
X
VGA
RF SMALL SIGNAL
Rx BPF
Rx BPF
Tx BPF
VCO
PLL
LNA
LNA
MPA
POWER AMPLIFIER
µC
HPA
MOUNTED
AMPLIFIER
RF POWER
LNA
LNA
TOWER
Isolator
duplexer
antenna
antenna
Tx/Rx
brb630
Rx1
3