W3030 Datasheet, PDF (3/22 Pages) Agere Systems – W3030 3 V Dual-Mode IF Cellular Receiver

Data Sheet
April 1999
W3030 3 V Dual-Mode IF Cellular Receiver
Description
The W3030 is a monolithic integrated circuit that
provides most of the receive path functions required
to meet the IS-136 (and IS-54) standard. The W3030
converts FM or digitally modulated IF carriers up to
200 MHz and provides required IF gain and separate
baseband detectors for the two modulation modes.
The W3030 is organized into three subfunctions (see
Figure 2):
1. First IF mixer/amplifier
2. Analog second IF
3. Digital second IF sections
(Note that the electrical specification tables
correspond to each subfunction.)
Each section has a buffered output to allow for
external filtering, which also provides flexibility in
system architecture selection. The first IF mixer
section provides 30 dB of fixed voltage conversion
gain (power gain = 17 dB). The first IF mixer also
performs down-conversion to the 0.2 MHz—2.0 MHz
range, which allows the use of inexpensive ceramic
filters at two points in the signal path. In the second IF
section, the signal path may be split between two
parallel amplifier/demodulator sections. In the analog
second IF, there is a 40 dB amplifier followed by a
60 dB hard-limiting amplifier and an FM quadrature
detector (noncoherent discriminator). The signal path
between the 40 dB and 60 dB amplifier stages is
brought off-chip for external filtering purposes. In
digital mode, an AGC amplifier provides gain between
10 dB and 80 dB. The digital signal is demodulated in
double-balanced mixers that are fed with an external
local oscillator (LO) signal. The external LO passes
through a divide-by-four counter to provide the final IF
LO frequency. This architecture greatly reduces the
possibility of feedback of the external LO signal to the
IF input, which would cause dc offsets at the I & Q
outputs. This circuit also provides a 90° phase shift of
the LO that is independent of duty cycle. The resulting
I & Q differential pairs can be level-shifted using the
VCM input pin, providing flexibility in interfacing to
digital processing ICs.
A pair of logic inputs allows the device to be put into a
powerdown mode and one of two partially enabled
modes (analog or digital only), or a fully enabled
mode, allowing the use of analog RSSI while in digital
receive mode.
Lucent Technologies Inc.
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