CML Microcircuits
COMMUNICATION SEMICONDUCTORS
D/608_18_38/10
August 2012
CMX608/CMX618/
CMX638
RALCWI Vocoders
Provisional Issue
Features
Near Toll Quality RALCWI Coding Algorithm
Multiple Bit Rate Modes:
2050, 2400 or 2750 bps
3600 bps with FEC Enabled
4-bit Viterbi Soft Decision Decoding
Integrated Audio CODEC (CMX618/CMX638 only)
Integrated Input and Output Channel Filters
20ms, 40ms, 60ms and 80ms Packet Lengths
No Licensing or Royalty Payments
Ancillary Audio Functions:
Voice Activity Detector
Comfort Noise Generator
DTMF and Single Tone Regeneration
1.8V Low Power Operation, 3.3V Tolerant I/O
Small 48-pin LQFP and VQFN Packages
Applications
Digital PMR, LMR, Voice Radio
Digital Trunking
DMR TDMA
DMR FDMA, dPMR
Digital Voice Scrambling and Encryption
Digital WLL
Voice Storage and Playback Systems
Regenerative Digital Voice Repeaters
Messaging Systems
VoIP Systems
Voice Pagers
Half-Duplex Vocoding (CMX608/CMX618)
Full-Duplex Vocoding (CMX638 only)
1.
Brief Description
The CMX608/CMX618/CMX638 are flexible, high integration, high performance, RALCWI (Robust
Advanced Low Complexity Waveform Interpolation) Vocoders, offering near toll quality voice at very low bit
rates. A Forward Error Correction (FEC) engine provides optimum performance in real life applications.
The RALCWI Vocoder comprises four independent functions which are selectable by the host: Voice
Encoder, FEC Encoder, Voice Decoder and FEC Decoder. The CMX608 and CMX618 are half-duplex
Vocoders and the CMX638 is a full-duplex Vocoder with integrated voice CODEC.The CMX618 includes
an integrated voice CODEC, offering a complete analogue voice to low bit rate vocoded data function, with
integrated channel filters removing the need for external components, whereas the CMX608 requires an
external voice CODEC.
CMX608/CMX618/CMX638 operate from a dual power supply (1.8V and 3.3V) and are available in both
48-pin LQFP (L4) and 48-pin VQFN (Q3) packages.
Continued overleaf .....
2012 CML Microsystems Plc
CMLMICRO [ CML MICROCIRCUITS ]
