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The 49xx Series RF Tuner
Modules are specifically
designed for subscriber-side
cable modem applications.
Downstream signal frequencies
range from 50 MHz to 860 MHz
(US) and 70 MHz to 862 MHz
(EU). Upstream signal
frequencies range from 5 MHz to
42 MHz (US) and 5 MHz to
65 MHz (EU).
The receivers use a three-band
single-conversion approach, with
a 43.75 MHz (US) or 36.125 MHz
(EU) output frequency. A second
conversion to 5.75 MHz (US) or
7.125 MHz (EU) is available for
QAM demodulators requiring a
lower IF center frequency.
Downstream band selection and
tuning is done via I
2
C bus while a
separate, three-wire bus and
transmit enable control the
upstream amplifier.
Two gain-control inputs (RF+IF)
are available to adjust the output
signal level. The tuner IF output
is designed to drive a low-pass
image-reject filter prior to the
QAM demodulator IC.
A DC/DC converter for 33V
generation is built in, so that only
a single supply voltage of 5V is
required.
The common antenna
input/output is realized by an F-
connector (75鈩? per [IPS-sp-
406].
Product Brief
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