Digital PMR Radio Processor
CMX7131/CMX7141
6.5.8 Tx Mode Preamble............................................................................................... 44
6.5.9 Tx Mode Mod Set-up............................................................................................ 44
6.5.10 Tx Mode Repeated Word..................................................................................... 44
6.5.11 Tx Sequencer....................................................................................................... 44
6.5.12 Rx Mode NXDN Formatted.................................................................................. 45
6.5.13 Rx Mode Raw....................................................................................................... 45
6.5.14 Rx Mode Eye........................................................................................................ 45
6.5.15 Rx Pass-through Mode ........................................................................................ 45
6.5.16 Rx Mode with CMX994 AGC (I/Q Mode only)...................................................... 46
6.5.17 Rx Mode with CMX994 I/Q Cal (l/Q Mode only)................................................... 46
6.5.18 Rx Mode with Powersave (I/Q Mode only)........................................................... 46
6.5.19 Reset/Abort .......................................................................................................... 47
6.5.20 Data Transfer ....................................................................................................... 47
6.5.21 CMX994 Pass-through Mode............................................................................... 48
NXDN Mode Operation............................................................................................... 49
6.6.1 Frame Format ...................................................................................................... 49
6.6.2 Addressing ........................................................................................................... 51
6.6.3 Rx Mode............................................................................................................... 51
Squelch Operation...................................................................................................... 53
GPIO Pin Operation.................................................................................................... 53
Auxiliary ADC Operation............................................................................................. 53
6.6
6.7
6.8
6.9
6.10
6.11
6.12
Auxiliary DAC/RAMDAC Operation ............................................................................ 54
RF Synthesiser (CMX7131 only) ................................................................................ 55
Digital System Clock Generators................................................................................ 58
6.12.1 Main Clock Operation........................................................................................... 58
6.12.2 System Clock Operation ...................................................................................... 59
6.13
Signal Level Optimisation ........................................................................................... 59
6.13.1 Transmit Path Levels ........................................................................................... 59
6.13.2 Receive Path Levels............................................................................................. 59
6.14
6.15
Tx Spectrum Plots ...................................................................................................... 60
C-BUS Register Summary.......................................................................................... 61
7
Performance Specification ................................................................................................... 62
7.1
Electrical Performance ............................................................................................... 62
7.1.1 Absolute Maximum Ratings ................................................................................. 62
7.1.2 Operating Limits................................................................................................... 63
7.1.3 Operating Characteristics..................................................................................... 64
7.1.4 Parametric Performance...................................................................................... 70
C-BUS Timing............................................................................................................. 71
Packaging................................................................................................................... 72
7.2
7.3
Table
Page
Table 1 Definition of Power Supply and Reference Voltages........................................................ 10
Table 2 Recommended External Components when using CMX994........................................... 17
Table 3 SPI-Codec Format ........................................................................................................... 20
Table 4 CMX994 Connections ...................................................................................................... 21
Table 5 NXDN Frame Format – Audio Communication................................................................ 26
Table 6 NXDN Frame Format – Data Communication ................................................................. 27
2014 CML Microsystems Plc
Page 4
D/7141_FI-3.x/6