16-Bit, First Complete Digital Modem on a Single Chip

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Replacement Parts

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Product Details

The ADSP-21mod870 digital modem processor is the first complete digital modem on a single chip. Digital modems are used in remote access servers (RAS). These servers contain banks of modems which receive dial-in calls from computer users seeking to connect to the Internet or to other networks.

The ADSP-21mod870’s small footprint and power efficiency will enable Internet Service Providers (ISPs) and central office access providers to quadruple the number of ports within the existing modem bank chassis. Moreover, the chip’s unique capability to support any protocol on any port will improve ISP customer service and reduce business operating costs.

Part of a family of digital modem solutions from ADI, the ADSP-21mod870 includes silicon, software and service. ADI is singular in its ability to provide the complete solution. Leadership in DSP and memory integration and a 30 -year signal processing focus are unique to Analog Devices, Inc.

Quadruple Number of Ports Today

The unprecedented level of integration found in the ADI solution provides the lowest cost per port, smallest space per port and lowest power consumption per port than any other solution available today. So, with the ADSP-21mod870, RAS OEMs can put up to four times as many modem ports within the existing modem chassis. The power supply and real estate requirements don’t change.

Any Protocol On Any Port

Companies serving the communications industry are faced with operating in an environment where their are many standards, or protocols, which are constantly evolving. The RAS market is no exception. The ADSP-21mod870 offers a unique solution. Based on an OEM-programmable digital signal processor running with its own on-chip Random Access Memory (RAM), the chip or modem port, can be reprogrammed on-demand. New protocols can be downloaded, existing protocols updated. All protocols may be resident, and loaded automatically depending on the user’s modem speed.

Acting as an "intelligent gateway", the ADSP-21mod870 helps lower ISP operating costs while raising customer satisfaction levels. Software upgrades are easy. ISPs eliminate the risks associated with choosing the mix of protocols to support, easing modem bank management.

Modem Software Features

On-chip Data Pump

- ISDN B-Channel HDLC
- Data Modulations
- K56Flex (30K-56K)
- ITU-T V.34
- CCITT V.32bis
- CCITT V.32

Start-up Procedures

- ITU-T V.8
- CCITT V.25


- CCITT V.42 Error Correction (LAPM&MNP)
- CCITT V.42bis data and MNP Class 5 Compression
- Software Interface API with Example Code