CMX868
Low Power
V.22 bis Modem
D/868/6 February 2002
Provisional Information
Features
•
V.22 bis 2400/2400 bps QAM
•
V.22, Bell 212A 1200/1200 or 600/600 bps DPSK
•
V.23 1200/75, 1200/1200, 75, 1200 bps FSK
•
Bell 202 1200/150, 1200/1200, 150, 1200 bps FSK
•
V.21 or Bell 103 300/300 bps FSK
•
DTMF/Tones Transmit and Receive
•
‘Powersave’ Standby Mode
Applications
•
Telephone Telemetry Systems
•
Remote Utility Meter Reading
•
Security Systems
•
Industrial Control Systems
•
Electronic Cash Terminals
•
Pay-Phones
•
Cable TV Set-Top Boxes
1.1
Brief Description
The CMX868 is a multi-standard modem for use in telephone based information and telemetry systems.
Control of the device is via a simple high speed serial bus, compatible with most types of µC serial
interface. The data transmitted and received by the modem is also transferred over the same serial bus.
On-chip programmable Tx and Rx USARTs meeting the requirements of V.14 are provided for use with
asynchronous data and allow unformatted synchronous data to be received or transmitted as 8-bit words.
It can transmit and detect standard DTMF and modem calling and answer signals or user-specific
programmed single or dual tone signals. A general purpose Call Progress signal detector is also included.
Flexible line driver and receive hybrid circuits are integrated on chip, requiring only passive external
components to build a 2 or 4-wire line interface.
The device also features a hook switch relay drive output and a Ring Detector circuit which continues to
function when the device is in the Powersave mode, providing an interrupt which can be used to wake up
the host µController when line voltage reversal or ringing is detected.
The CMX868 operates from a single 2.7 to 5.5V supply over a temperature range of -40°C to +85°C and
is available in 24-pin TSSOP, SOIC and DIP packages.
©
2002 Consumer Microcircuits Limited
CMLMICRO [ CML MICROCIRCUITS ]
