CMX7241 Datasheet, PDF (3/94 Pages) CML Microcircuits – Voice processing

PMR Common Platform Processor
CMX7241/CMX7341
Section
CONTENTS
Page
1 Brief Description...................................................................................................................... 2
2 Block Diagram ......................................................................................................................... 8
3 Signal List................................................................................................................................. 9
3.1 Signal Definitions ........................................................................................................ 11
4 Component and PCB Recommendations ........................................................................... 12
4.1 Recommended External Components ....................................................................... 12
4.2 PCB Layout Guidelines and Power Supply Decoupling ............................................. 15
4.3 CMX994 Interface....................................................................................................... 17
4.4 Serial Port Interfaces .................................................................................................. 19
4.5 RESET Pin.................................................................................................................. 19
5 General Description .............................................................................................................. 20
5.1 7241/7341FI-1 Features ............................................................................................. 20
5.2 Digital Features .......................................................................................................... 20
5.3 Analogue Features ..................................................................................................... 21
5.4 Auxiliary Functions ..................................................................................................... 21
5.5 Interface...................................................................................................................... 21
5.6 System Design ........................................................................................................... 22
5.6.1 General ................................................................................................................ 22
5.6.2 Implementation using the CMX6x8 and CMX7262.............................................. 22
5.6.3 Implementing with Third-party Vocoders ............................................................. 24
5.6.4 Data Transfer ....................................................................................................... 25
5.6.5 CMX994 Connection (I/Q Mode).......................................................................... 25
5.6.6 Hardware AGC – AuxADC1 Connection ............................................................. 26
5.6.7 RSSI Measurement (I/Q Mode) ........................................................................... 26
5.6.8 RSSI Measurement (LD mode)............................................................................ 26
5.7 dPMR Modem Description.......................................................................................... 27
5.7.1 Modulation............................................................................................................ 27
5.7.2 Internal Data Processing...................................................................................... 29
5.7.3 Frame Sync Detection and Demodulation ........................................................... 30
5.7.4 FEC and Coding................................................................................................... 33
5.7.5 Voice Coding........................................................................................................ 34
5.7.6 Radio Performance Requirements....................................................................... 34
5.8 Audio/Voice Functions ................................................................................................ 34
5.8.1 Microphone .......................................................................................................... 34
5.8.2 Speaker................................................................................................................ 34
5.8.3 Modulation............................................................................................................ 34
5.8.4 Audio / Voice processing ..................................................................................... 34
5.8.5 Sub-Audio Signalling............................................................................................ 35
5.8.6 In-band Signalling ................................................................................................ 35
6 Detailed Descriptions ............................................................................................................ 36
6.1 Xtal Frequency ........................................................................................................... 36
 2015 CML Microsystems Plc
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