SL1925
Satellite Zero IF QPSK Tuner IC
Preliminary Information
DS4955
Issue - 2.0
March 1999
Features
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Ordering Information
SL1925/KG/NP2S (Tubes)
SL1925/KG/NP2T (Tape and Reel)
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Single chip system for direct quadrature down
conversion from L-band
High signal handling capability for minimum
external component count application, requires
external RF AGC of 30dB
Compatible with DSS and DVB system
requirements
Excellent gain and phase match up to 30MHz
baseband
High output referred linearity for low distortion and
multi channel application
Fully balanced low radiation design
Integral RF AGC amplifier
Two selectable varactor tuned local oscillators
with buffered output for driving external
synthesiser loop
ESD protection (Normal ESD handling procedures
should be observed)
Description
The SL1925 is a wideband quadrature converter operating
from 950 to 2150 MHz, intended primarily for application
in satellite tuners.
The device contains all elements necessary, with the
exception of local oscillator sustaining network, to fabricate
a high performance I(n-phase) & Q(uadrature) phase
splitter and downconverter optimised for systems
containing RF AGC gain control. The device allows for
systems containing higher power analog interferers. For
most applications RF tunable filtering is not essential.
The SL1925 is optimised for use with a low phase noise
synthesiser, a range of which are available from Mitel
Semiconductor. This will form a complete front end tuner
function for digital satellite receiver systems utilising DSP
derotation recovery.
The device includes a very high signal handling front end
with AGC, this provides for gain control, reference local
oscillator with output buffer, phase splitter with I and Q
mixers and baseband buffer amplifiers with external
interstage filtering.
Applications
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Satellite receiver systems
Data communications systems
MITEL [ MITEL NETWORKS CORPORATION ]
