GMSK Modem
CMX589A
Section
Contents
Page
Features and Applications .................................................................................................1
Brief Description .................................................................................................................1
Block Diagram .....................................................................................................................2
2 Signal List .........................................................................................................................4
3 External Components ......................................................................................................6
4 General Description .........................................................................................................8
4.1 Clock Oscillator Divider......................................................................................................... 8
4.2 Receive ................................................................................................................................ 8
4.2.1 Rx Signal Path Description..........................................................................................................8
4.2.2 Rx Circuit Control Modes.............................................................................................................9
4.2.3 Rx Clock Extraction ...................................................................................................................10
4.2.4 Rx Data Extraction.....................................................................................................................10
4.2.6 Rx Signal Quality .......................................................................................................................12
4.3 Transmit ............................................................................................................................. 12
4.3.1 Tx Signal Path Description ........................................................................................................12
4.4 Data Formats...................................................................................................................... 15
4.5 Acquisition and Hold Modes ............................................................................................... 15
5 Application......................................................................................................................16
5.1 Radio Channel Requirements............................................................................................. 16
5.1.1 Bit Rate, BT, and Bandwidth .....................................................................................................16
5.1.2 FM Modulator, Demodulator and IF...........................................................................................16
5.1.3 Two-Point Modulation................................................................................................................17
5.2 AC Coupling of Tx and Rx Signals...................................................................................... 18
6 Performance Specifications ..........................................................................................19
6.1 Electrical Specifications ...................................................................................................... 19
6.1.1 Absolute Maximum Limits..........................................................................................................19
6.1.2 Operating Limits ........................................................................................................................20
6.1.3 Operating Characteristics ..........................................................................................................21
6.2 Packages............................................................................................................................ 23
© 1998 Consumer Microcircuits Limited
2
D/589A/3