Bell 202 Compatible Modem

FX614

© 1997 Consumer Microcircuits Limited

2

D/614/4

CONTENTS

Section

Page

1.0 Features ......................................................................................................1

1.1 Brief Description.........................................................................................1

1.2 Block Diagram ............................................................................................3

1.3 Signal List ...................................................................................................3

1.4 External Components.................................................................................5

1.5 General Description....................................................................................5

1.5.1 Xtal Osc and Clock Dividers .......................................................5

1.5.2 Mode Control Logic ....................................................................6

1.5.3 Rx Input Amplifier .......................................................................6

1.5.4 Receive Filter and Equaliser.......................................................6

1.5.5 Energy Detector ..........................................................................7

1.5.6 FSK Demodulator........................................................................7

1.5.7 FSK Modulator and Transmit Filter............................................7

1.5.8 Rx Data Retiming ........................................................................9

1.5.9 Tx Data Retiming.......................................................................10

1.6 Application Notes .....................................................................................12

1.6.1 Line Interface.............................................................................12

1.7 Performance Specification.......................................................................13

1.7.1 Electrical Performance..............................................................13

1.7.2 Packaging ..................................................................................16