CMX867AE2

Overview

The CMX867AE2 is a low-power V.22 modem integrated circuit manufactured by CML Microcircuits, designed for telephone-based information and telemetry systems. It supports multiple standards including V.22, Bell 212A (DPSK), V.23, Bell 202, V.21, and Bell 103 (FSK). The device operates on a single 2.7V to 5.5V supply within a temperature range of -40°C to +85°C. It features programmable Tx and Rx USARTs compliant with V.14, an on-chip DTMF encoder/decoder, flexible line drivers, and a ring detector. Control and data transfer are managed via a high-speed serial C-BUS interface compatible with microcontrollers.

Feature Summary

• Multi-standard modulation support for V.22, Bell 212A, V.23, Bell 202, V.21, and Bell 103 protocols.
• Integrated programmable transmit and receive USARTs meeting V.14 requirements for asynchronous and synchronous data handling.
• On-chip DTMF/Tone generator and decoder with immunity to falsing on voice signals.
• Flexible line driver and receive hybrid circuits requiring only passive external components for 2-wire or 4-wire interfaces.
• Powersave standby mode that disables most circuitry while maintaining ring detection and interrupt capabilities.

Applications

• Telephone Telemetry Systems
• Remote Utility Meter Reading
• Security Systems
• Industrial Control Systems
• Electronic Cash Terminals

Procurement Notes

Verify the specific package variant required, as the CMX867A family is available in 24-pin TSSOP, SOIC, and DIP packages. Confirm RoHS compliance status directly with the manufacturer or authorized distributors, as environmental certifications may vary by production batch. Ensure the ordering suffix matches the desired physical footprint and lead-free specifications before finalizing procurement orders.

Selection Notes

Select the CMX867AE2 when a multi-standard modem solution is needed for legacy telephone networks supporting both FSK and DPSK modulation schemes. Consider this component for designs requiring integrated DTMF functionality and low power consumption in standby modes. Verify that the host microcontroller can interface with the C-BUS serial protocol used for control and data exchange.

Part Context

The CMX867AE2 belongs to the CMX867A series of communication semiconductors from CML Microcircuits. It serves as a specialized interface for analog telephone lines, bridging digital microcontroller systems with traditional telephony infrastructure. The device is part of a broader portfolio of telecom interface ICs designed for robust signal processing in noisy environments.

Replacement Considerations

The CMX867AE2 is software and hardware compatible with the CMX868A. Designers upgrading from or migrating to other models should verify register compatibility and pinout alignment to ensure seamless integration without significant schematic modifications.