CML Semiconductor Products
PRODUCT INFORMATION
FX002
Signal to Noise Enhancer
Publication D/002/2 July 1994
Features
Applications
Up to 8.5dB Signal-to-Noise
Radio Communications and
Improvement
Paging Systems
Input Frequency Range: 17Hz to 13kHz
Tone Detection
[Sub-Audio and Audio Frequencies]
Sonar Detection and Analysis
Low-Voltage Operation: 2.5 Volts
Slow Data-Rate Communications
10mVrms Minimum Signal Input
Medical Equipment
Digital Output Signal (f
IN
x 4)
Interference Investigation
鈥楧ivided-Down鈥?Clock Outputs
SIGNAL BIAS
SIGNAL IN
-
+
DELAY
48-BIT
COMPARE
LOGIC
INTERPOLATE
DELAY
24-BIT
OUTPUT
[4 x SIGNAL IN]
OUTPUT
LOGIC
V
DD
DELAY
48-BIT
COMPARE
LOGIC
INTERPOLATE
V
SS
AUTOCORRELATION
PROCESS
DELAY
24-BIT
FX002
CLOCK
OUTPUT
6
CLOCKS
XTAL/CLOCK
XTAL/CLOCK
GENERATOR/
DIVIDER
XTAL
CLOCK
OUTPUT
24
Fig.1 Functional Block Diagram
Brief Description
The FX002 is a single-chip device to extract single
periodic signals from very high random-noise
environments.
Using patented autocorrelation techniques the
FX002 will enhance the input signal's signal-to-noise
ratio by as much as 8.5dB and provide a digital output
signal centred at four times (x4) the input frequency.
The amplitude of non-periodic components of the
signal is substantially reduced. The patented
autocorrelator compares the incoming signal to itself;
the more elements of the waveform that are seen as
periodic, the higher the energy at the microcircuit
output.
The FX002 cascades two autocorrelators, each one
improving the signal-to-noise ratio.
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With a random noise input the output will swing
rail-to-rail at random (peak-limited). The input/output
signal delay is fixed by the choice of clock frequency
and the length of the internal register. The FX002 will
operate at supply voltages of between 2.5 volts and
5.5 volts and with Xtal/clock frequencies from 20kHz to
2.5MHz. Using various Xtal/clock inputs the device can
be set to accept input signal frequencies, in bands,
from 17.0Hz to 13.0kHz.
Two uncommited clock outputs are available to
supply 'divided-down' Xtal/clock frequencies for use in
external and peripheral functions.
This low-power signal processing device is
available in 16-pin cerdip dual-in-line (DIL) and plastic
small outline (S.O.I.C.) surface mount packages.
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