FX105A

Tone Detector

© 1999 Consumer Microcircuits Limited

D/105A/5 September 1999

1.0

Features

Provisional Issue

•• Operates in High Noise Conditions

•• Adjustable Bandwidth

•• ≥≥ 36dB Signal Input Range

•• Adjustable Frequency

•• High Sensitivity

•• Wide Voltage Range (2.7V to 5.5V)

•• Low Power

•• Single and Multitone System

Applications

1.1

Brief Description

The FX105A is a monolithic CMOS tone operated switch, designed for tone decoding in single and

multitone signalling systems. The FX105A uses decoding techniques which allow a tone to be

recognised in the presence of high noise levels or strong adjacent signals. Detection centre frequency

and bandwidth can each be independently adjusted. The design is immune to high levels of harmonic

and sub-harmonic interference. Excellent noise immunity and constant bandwidth are maintained over

a wide range of input signal levels.