CMX883 Ver la hoja de datos (PDF) - CML Microsystems Plc

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componentes Descripción

Fabricante

CMX883

Baseband Processor for ‘Leisure Radios’

CML Microsystems Plc 

FRS Signalling Processor

CMX883

Section

CONTENTS

Page

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

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

1.2 Block Diagram...............................................................................................................7

1.3 Signal List .....................................................................................................................8

1.4 External Components .................................................................................................. 10

1.4.1 PCB Layout Guidelines and Power Supply Decoupling ................................... 11

1.4.2 Modulator Outputs .......................................................................................... 12

1.5 General Description..................................................................................................... 13

1.5.1 Sleep Mode and Auto Start Up........................................................................ 15

1.5.2 Auxiliary ADC ................................................................................................. 15

1.5.3 Receive Mode................................................................................................. 16

1.5.4 Transmit Mode................................................................................................ 24

1.5.5 XTCSS Coding................................................................................................ 27

1.5.6 C-BUS Operation ............................................................................................ 29

1.6 C-BUS Register Description ........................................................................................ 30

1.7 Application Notes ........................................................................................................ 48

1.8 Performance Specification........................................................................................... 49

1.8.1 Electrical Performance.................................................................................... 49

1.8.2 Packaging....................................................................................................... 57

Table

Page

Table 1 Voice Processing Combinations ................................................................................... 14

Table 2 Concurrent Rx Signalling Modes Supported by the CMX883 ....................................... 16

Table 3 CTCSS Tones ............................................................................................................. 20

Table 4 DCS Modulation Modes............................................................................................... 20

Table 5 DCS 23 Bit Codes ....................................................................................................... 21

Table 6 In-band Tones ............................................................................................................. 22

Table 7 Concurrent Tx Modes Supported by the CMX883 ........................................................ 24

Figure

Page

Figure 1 Block Diagram ............................................................................................................. 7

Figure 2 Recommended External Components ........................................................................ 10

Figure 3 Power Supply Connections and De-coupling .............................................................. 11

Figure 4 Modulator output components to achieve -100dB/decade roll-off................................ 12

Figure 5 Rx Audio Filter Frequency Response ......................................................................... 17

Figure 6 De-emphasis Curve for TIA/EIA-603 Compliance....................................................... 17

Figure 7 Low Pass Sub-Audio Band Filter for CTCSS and DCS ......................................... 18

Figure 8 25kHz Channel Audio Filter Response Template........................................................ 25

Figure 9 12.5kHz Channel Audio Filter Response Template..................................................... 25

Figure 10 Audio Frequency Pre-emphasis Template ................................................................ 26

Figure 11 C-BUS Transactions................................................................................................. 29

Figure 12 Possible FRS Configuration ..................................................................................... 48

Figure 13 C-BUS Timing.......................................................................................................... 56

Figure 14 Mechanical Outline of 28-pin SSOP (D6): Order as part no. CMX883D6 ................ 57

Figure 15 Mechanical Outline of 28-pin TSSOP (E1): Order as part no. CMX883E1 .............. 57

 2004 CML Microsystems Plc

5

D/883/7

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