深圳人本润金科技有限公司

CMX7261

Multi-transcoder

 2012 CML Microsystems Plc

D/7261_FI-1.x/9 March 2012 DATASHEET Advance Information

7261 FI-1.x Multi-transcoder

Features

  Half-duplex operation

  Full-duplex operation

  Multiple codec support:

o  PCM (linear, μ-law, A-law), CVSD and

G.729A codecs

  Multiple transcoding support:

o  PCM to CVSD and reverse

o  PCM to G.729A and reverse

o  CVSD to G.729A and reverse

o  PCM μ/A/linear to PCM μ/A/linear

transcoder

  No external DSP or codecs required: simply

upload Function Image™ (FI)

  Transcoder routing:

o  Choice of input sources – C-BUS transfer

to host, external PCM device/codec,

analogue audio input

o  Choice of output sources – C-BUS transfer

to host, external PCM device/codec,

analogue audio output

  Voice activity detection

  C-BUS host serial interface

o  SPI-like with register addressing

o  Read/Write 128-byte FIFOs and data buffers

to streamline transfers and relax host service

latency

  Auxiliary functions

o  Three GPIOs

o  Analogue input/output gain adjustment

o  Analogue input multiplexer

o  Analogue output multiplexer

  Master/Slave PCM serial interface

o  For external audio CODEC

  Low power 3.3V operation with powersave

functions

  Small 64-pin VQFN/LQFP package

Applications

  Half duplex digital radio systems

  Full duplex digital radio systems

  Personal area network voice links

  Privacy-type digital voice communications

  Wireless PBX

  VoIP applications

  Digital Software Defined Radio (SDR)

Transcoder

Function

Image™

Host

μC

Registers

FIFO

Configuration

Digital

Filters

Digital

Filters

DAC

ADC

Analogue Out

Analogue In

3.3V

External ADC /

DAC

PCM Talk-

Through /

PCM

3.3V

C-BUS

CMX 7261

Multi- - transcoder

Transcoder

GPIOs

Datasheet

User

Manual

This document contains:

CMX7261 Voice Multi-transcoder  CMX7261

 2012 CML Microsystems Plc  Page 2  D/7261_FI-1.x/9

1  Brief Description

The CMX7261 Multi-transcoder IC is a device supporting multiple speech codecs in a single chip. The

CMX7261 is capable of encoding analogue voice into PCM (linear, μ-law or A-law), CVSD or G.729A data

formats. It is capable of decoding PCM, CVSD and G.729A back to analogue voice. It can also transcode

data between PCM, CVSD and G.729A.

Input and output signals may be passed through the C-BUS interface, the PCM port or the on-chip

convertors (ADC/DAC).

The device utilises CML’s proprietary FirmASIC  component technology. On-chip sub-systems are

configured by a Function Image™ data file that is uploaded during device initialisation and defines the

device's function and feature set. The Function Image™ can be loaded automatically from a host μC over

the C-BUS serial interface or from an external memory device. The device's functions and features can be

enhanced by subsequent Function Image™ releases, facilitating in-the-field upgrades.

The CMX7261 operates from a 3.3V supply and includes selectable powersaving modes. It is available in

a 64-VQFN (Q1) or a 64-LQFP (L9) package.

Note that text shown in pale grey indicates features that will be supported in future versions of the device.

This Data Sheet is the first part of a two-part document.