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PRODUCT INFORMATION

CML Semiconductor Products

FX002

Features

Up to 8.5dB Signal-to-Noise

Improvement

Input Frequency Range: 17Hz to 13kHz

[Sub-Audio and Audio Frequencies]

Low-Voltage Operation: 2.5 Volts

10mVrms Minimum Signal Input

Digital Output Signal (f

‘Divided-Down’ Clock Outputs

Applications

Radio Communications and

Paging Systems

Tone Detection

Sonar Detection and Analysis

Slow Data-Rate Communications

Medical Equipment

Interference Investigation

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.

Signal to Noise Enhancer

Publication D/002/2 July 1994

FX002

Fig.1 Functional Block Diagram

SIGNAL IN

SIGNAL BIAS

AUTOCORRELATION

PROCESS

OUTPUT

[4 x SIGNAL IN]

XTAL/CLOCK

CLOCKS

XTAL

XTAL/CLOCK

GENERATOR/

DIVIDER

-

+

DELAY

48-BIT

COMPARE

LOGIC

DELAY

48-BIT

INTERPOLATE

INTERPOLATE

OUTPUT

LOGIC

DELAY

24-BIT

COMPARE

LOGIC

DELAY

24-BIT

CLOCK

6

OUTPUT

CLOCK

24

OUTPUT

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.