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RF SILICON AND SYSTEMS SOLUTIONS
FOR BROADBAND COMMUNICATIONS, AUTOMOTIVE ELECTRONICS AND WIRELESS CONNECTIVITY
MT1550 UPSTREAM
AMPLIFIER
PRODUCT BRIEF
The MT1550 is a low-cost
programmable-gain power amplifier
IC for use in CATV upstream
applications. The Microtune
®
MT1550 is a 3.3 volt part optimized
®
for the DOCSIS 1.0, 1.1, 2.0 and
MT1550 APPLICATIONS
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Cable modems
Telephony over cable
Set-top box CATV
The MT1550 is a 3.3V
programmable gain upstream
amplifier with integrated anti-
aliasing filter.
MT1550 Upstream Amplifier
Euro-DOCSIS™ upstream standard.
An on-chip input anti-aliasing filter is
included to reduce external system
costs.
The device’s specified frequency
range is from 5 MHz to 65 MHz, with
an output P1dB > 67 dBmV through
a 1:1 impedance-ratio transformer.
A 3-wire digital serial bus controls
the variable gain, with gain control
available in 1 dB steps and a
nominal 59 dB gain range.
The MT1550 may be disabled via
an external control pin. The transmit-
disable mode not only minimizes
output noise by shutting off the
output stage, but also maintains its
output impedance at nominal levels.
Output transients are nominally less
than 16 mVp-p at 61 dBmV output
level during transmit enable/disable
switching.
Operating from a single 3.3 V
supply, the amplifier typically draws
247 mA at maximum gain or
minimum attenuation. Additional
internal circuitry reduces the
amplifier’s power consumption
depending on gain setting.
Transmit-disable mode reduces the
typical current draw to 60 mA, while
shutdown mode further reduces it to
85
µA.
The MT1550 is available in a 20-
pin Quad Flat No-Lead (QFN)
package with an exposed pad for
the extended industrial temperature
range of -40°C to +85°C.
FEATURES
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Integrated on-chip anti-
aliasing filter
P1dB of 67 dBmV
Low power-up/down
transients of 16 mVp-p typical
at 61 dBmV output
Ultra low third harmonic
distortion
Single 3.3 V supply
59 dB gain range
Gain programmable in 1 dB
steps
Low transmit output noise
floor: -50 dBmV in 160 kHz
Low transmit-disable output
noise: -68 dBmV
Two power-down modes
DOCSIS 1.0, 1.1, 2.0 and
Euro-DOCSIS compatible
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M I C R O T U N E
MICROTUNE [ MICROTUNE,INC ]
