Digital Voice
CMX618/638 – RALCWI Vocoder IC’s
As a members of the CML DuraTALK family of digital voice products, the CMX618/CMX638 are flexible, high integration, high performance, RALCWI Vocoder, offering near toll-quality voice at very low bit rates.
- CMX618: Half-duplex RALCWI Vocoder with Integrated Voice Codec
- CMX638: Full-duplex RALCWI Vocoder with Integrated Voice Codec
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 CMX618 includes an integrated voice CODEC, offering a complete analogue voice to low bit rate vocoded data function, with integrated channel filters, which removes the need for external components.
Both devices 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.
Function Add-ins
New features or enhancements to aid Vocoder operation are available. Function Add-ins currently available:
- Voice Store and Retrieve (VSR)
- Noise Gate
- Encryption
- Fine Analogue Output Gain Option
Devices are available through our Distributor Network.
Features
- RALCWI™ CML’s Digital Voice Technology
- Near Toll Quality RALCWI™ Coding Algorithm
- No royalty/license fee
- Multiple Bit-Rate Modes
– 2400 or 2750 bps
– 3600 bps with FEC Enabled - 4-bit Viterbi Soft Decision Decoding
- Integrated Voice Codec(CMX618 and 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 - Voice Store and Retrieve, Encryption and Noise Gate. Fine Analogue Output Gain. Function Add-ins Available
- Voice Activity Detector, DTMF/Tone generator, comfort noise generator, soft decision decoding
Applications
- Digital PMR, LMR, DMR TDMA, DMR FDMA, dPMR
- Digital Trunking, Digital WLL
- Digital-voice Scrambling and Encryption
- Voice-storage and Playback Systems
- Messaging Systems
- VoIP Systems
- Voice Pagers
- Regenerative Digital Voice Repeaters
Power Supply Requirement
- 1.8V, 3.3V Tolerant I/O
Design Resources
| PE0003
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The PE0003 Evaluation Kit Interface Card is a global interface system for use with evaluation kits for CML’s new generation ICs, including FirmASIC™ based products. This greatly simplifies the approach to the evaluation and design-in process.
Documents |
| EV6380
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The EV6380 Evaluation Kit allows rapid and full evaluation of the CMX638 and can also be used in half-duplex mode to demonstrate the operation of the CMX618.
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FAQs
Q: My EV6180 Evaluation Kit will not operate when JP2 is fitted. Why is this? A: JP2 connects the hard-reset circuit on the EV6180 to pin 16 of the C-BUS connector J3. On the PE0003, this pin is set to input by default and a weak pull-up applied. It is possible that the reset signal will be applied until C-BUS pin 16 is actively driven low by a PE0003 script. Removing JP2 disconnects the hard-reset circuit from C-BUS pin 16. The power-on reset and the C-BUS General Reset command will function as normal with JP2 removed. EV6380 Hi-Res Schematic EV6380 Hi-res schematic for board version C, MOD state 2. – Download Scripts Full-duplex speech demonstration on the EV6380 Evaluation Kit. – Download |
