MT8880CN1

MT8880CN1 is a multi-functional signal processor integrated circuit developed by Motorola, mainly used for line interface controller applications and signal processing applications. It is mainly for public electronic equipment, public telephone exchanges, customer premise and access systems.

Application Field

Through the use of the transceiver function and the advanced signal processing functions of the MT8880CN1, it is possible to quickly and accurately transmit various voice, low-bit-rate data, and graphic data signals of the subscriber line interface. The MT8880CN1 can be used to systematize a variety of circuits in central office application systems, such as conference bridges, subscriber line interfaces, line testing, ADSL modems, multimedia systems, and similar hardware. Some examples of the applications of the MT8880CN1 are:

• Subscriber line interfaces in telecommunication systems;
• Access multiplexers such as VF, LMDS and IMTS over fiber systems;
• Desktop and mobile phones;
• Telephone answering and voicemail systems;
• Cable modems;
• Interactive voice response systems;
• Analog voice systems.

Working Principle

The MT8880CN1 chip has two sub-circuits inside, namely a DSP sub-circuit and a micro-controlled sub-circuit. The high-density logic circuits, analog circuits and arithmetic logic circuits integrated in the MT8880CN1 allow it to achieve multi-functional signal processing and interface control functions. The chip adopts programmable digital signal processing, making it very suitable for voice, data and graphic signal processing applications. The chip has three channels, each channel with a adjustable transmit and receive buffer. Its’ most common applications are in subscriber line interfaces and various digital access systems.

The MT8880CN1 has a sound frequency detection circuit and a DTMF detection circuit. The sound frequency detection circuit can detect frequencies from 500 Hz to 3414 Hz and the DTMF detection circuit can detect the dual tone multifrequency tones of the telephone keypad. The switching control portion of the chip integrated 3-state monitor circuit, a four-wire loop current driver, an off-hook detector, a ring detector and four AMI (Alternative Mark Inversion) compatible output ports. The four AMI output ports work under the control of the micro-controlled sub-circuit, allowing it to recognize the dual tone multifrequency tones and dial the number. The chip is also equipped with a variety of power protection circuits and hardware that protect the chip from electrical damage.

The MT8880CN1 has excellent performance and can provide developers with powerful support for achieving rapid and accurate transmissions of various signals. It is a reliable, economical and highly integrated integrated circuit, enabling a variety of applications such as desktop and mobile phones, multimedia systems and voice response systems.