- Resources:
- datasheet
- |
- data updates
- |
- FAQs
- |
- application notes
- |
- evaluation
- |
- innovations
- |
Features
- V.22bis, V.22, Bell212A, V.23/Bell 202, V.21/Bell Modulation Schemes
- DTMF/Tones: Tx and Rx
- Line Reversal and Ring Detection
- Line Power Capabilities
- 'Gyrator' and 'Anti-Reflective' Load Control
- Parallel Phone Detection
- DE8781 DemoKit Available
Applications
- Line-Powered Telephone Data
- Payphone Management
- Remote Utility Meter Reading
- Electronic Point-of-Sale Terminals (EPOS)
- Telephone Telemetry Systems
- Cable TV Set-Top Boxes
- Automatic Teller Machines (ATM)
- Electronic Cash Terminals
- Internet and E-mail Terminals
- Security Systems
- Home Automation
Package Styles:
- CMX878D1 - CMX878D6 - CMX878E1
Supply Requirement:
2.7V power supply
Description
The CMX878 is a line-powered V.22bis-based multi-standard modem for use in telephone based information and telemetry systems. It provides the building blocks for interfacing to the telephone line without the need for a transformer - this is the Data Access Arrangement (DAA) – allowing for the coupling of data signals to and from the line; it can also detect Ringing and Line Reversals.
Provision is made for the conditioning and monitoring of other aspects of the telephone line – this includes the gyrator/DC mask, anti-reflective (AR) impedance control, and line voltage measurement. A complete line interface can be implemented with a small external component count, using low cost components.
Very low power consumption and built-in power management makes the CMX878 suitable for telephone line power usage. Furthermore the microprocessor can be de-powered whilst awaiting the detection of a Ring, Line Reversal, or WAKE pin event.
Control of the device is via a simple high speed serial bus, compatible with most types of µC serial interface. Data transmitted and received by the modem is transferred over the same serial bus.
The CMX878 is a line-powered V.22bis-based multi-standard modem for use in telephone based information and telemetry systems. It provides the building blocks for interfacing to the telephone line without the need for a transformer - this is the Data Access Arrangement (DAA) – allowing for the coupling of data signals to and from the line; it can also detect Ringing and Line Reversals.
Provision is made for the conditioning and monitoring of other aspects of the telephone line – this includes the gyrator/DC mask, anti-reflective (AR) impedance control, and line voltage measurement. A complete line interface can be implemented with a small external component count, using low cost components.
Very low power consumption and built-in power management makes the CMX878 suitable for telephone line power usage. Furthermore the microprocessor can be de-powered whilst awaiting the detection of a Ring, Line Reversal, or WAKE pin event.
Control of the device is via a simple high speed serial bus, compatible with most types of µC serial interface. Data transmitted and received by the modem is transferred over the same serial bus.
