ARA05050
Reverse Amplifier with Step Attenuator
Data Sheet - Rev 2.2
FEATURES
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Low Cost Integrated Monolothic GaAs Amplifier
With Step Attenuator
Attenuation Range: 0-30 dB, Adjustable In
2dB Increments Via a 4 Wire Parallel Control
Meets DOCSIS Distortion Requirements at
+58dBmV Output Signal Level
Low Distortion and Low Noise
Low Signal toNoise Ratio at All Gain Levels
Frequency Range: 5-100 MHz
5 Volt Operation
RoHS-Compliant Package Option
APPLICATIONS
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MCNS/DOCSIS Compliant Cable Modems
CATV Interactive Set-Top Box
OpenCable Set-Top Box
Fiber Nodes
Cable Modem Termination Systems (CMTS)
S12 Package
28 Pin SSOP with Heat Slug
PRODUCT DESCRIPTION
The ARA05050 is a GaAs IC designed to provide the
reverse path amplification and output level control
functions in a CATV Set-Top Box or Cable Modem. It
incorporates a digitally controlled precision step
attenuator that is preceded by an ultra low noise
amplifier stage, and followed by an ultra-linear output
driver amplifier. This device is capable of meeting
the MCNS/DOCSIS requirements for harmonic
4
Attenuation Control
performance at a +58dBmV output level while
requiring only a single polarity +5V supply. Both the
input and the output are single-ended and matched
to 75 Ohms. The precision attenuator provides up to
30 dB of attenuation in 2 dB increments. The
ARA05050 is offered in a 28-pin SSOP package that
features a heat slug on the bottom of the package,
and is available in a RoHS-compliant option.
Switch
ARA05050
LPF
Balun
Upstream
QPSK/16QAM
Modulator
Clock
Data
RAM
ROM
5-42 MHz
Transmit Enable/Disable
MAC
Clock
Data
Microcontroller
with Ethernet
MAC
Diplexer
54-860 MHz
Double-
Conversion
Tuner
44 MHz
SAW
Filter
QAM Receiver
with FEC
10Base-T
Transceiver
RJ45
Connector
Figure 1. Cable Modem or Set Top Box Application Diagram
05/2005
ANADIGICS [ ANADIGICS, INC ]
