Highly integrated line powered modem IC

Edited by the Electronicstalk editorial team Apr 8, 2002

Cost-and-power sensitive data collection and telemetry equipment will benefit from a new V.22bis modem IC from Flint, featuring an on-chip AT command interpreter.

Cost-and-power sensitive data collection and telemetry equipment will benefit from a new V.22bis modem IC from Flint, featuring an on-chip AT command interpreter.

The Consumer Microcircuits CMX866 operates at 5mA from a single 2.7V supply, meeting the low power requirements of line powered, telephone-based applications.

In addition to its AT support the device features hardware support for V.23 and Bell 202 Fast Turnaround operation.

Flint says the 24-pin TSSOP package makes the CMX866 the smallest semiconductor modem currently available.

Further package options include 24-pin SOIC and DIP.

An evaluation kit, EV8680, can also be ordered through Flint for rapid development of low-cost datacomms solutions.

The CMX866 delivers multi-mode capability with extremely low power requirements, and can operate at 2400bit/s full duplex over two- or four-wire circuits.

Compared with high speed modems, the V.22bis CMX866 eliminates the longer call set up time of high speed protocols, reducing equipment costs, telephone time and power overhead when transmitting small packets of data.

The CMX866 also supports V.22, Bell 212A, V.23, Bell 202, V.21 and Bell 103 protocols.

Low operating power, plus a "zero-power" standby mode, makes the CMX866 suitable for deployment on customer premises, in remote locations or in other situations where minimum power consumption is desirable.

In the standby mode, a ringing voltage or line reversal can activate the device by triggering a "wake-up" interrupt for the host microprocessor.

An on-chip integrated DTMF encoder/decoder can be used during dial out or dial in, allowing a data call to be set up easily by the microcontroller.

The CMX866 also includes an on-chip answer/originate generator and detector and a call progress tone detector, to further simplify call setup.

A simple high speed serial control bus and on-chip UART are also provided, enabling easy integration of the hardware with a host microcontroller.

The CMX866 is supported by the EV8680 evaluation kit comprising a single board containing a CMX866 Modem IC, line interface components and a PIC microcontroller with serial communications port for interfacing to a PC.

The onboard AT command interpreter enables data exchange with industry standard PC modems.

The kit is powered from a single power supply, with on-board regulation provided for 2.7 or 5.0V operation.

LED indicators and monitoring points for important signals are provided.

A two-wire line interface provides line matching and DC isolation, and space is provided for the user to add network-specific components to meet line impedance, line protection or other requirements.