Introduction

The DSP1648C, host-accelerated modem chip is an exciting new upgrade to Agere Systems Inc. line of host-based controller modems. The DSP1648C upgrades the technologies found in the DSP1648 V.90 modem solution to the new ITU-T recommendations V.92 and V.44 communication industry standards. V.92 and V.44 have four innovative features, designed to improve modem performance in the internet environment. The new features are as follows:

■ Modem fast connect: faster start-up times.

■ Modem on hold?: switch between modem and an incoming phone call without losing the data connection.

■ PCM upstream: send data to central site at rates approaching 48 kbits/s.

■ Data compression enhancement focused on todays internet traffic.

特性 Features

■ Two chip 3.3 V PCI modem solution with 5 V tolerant buffers

■ Data mode capabilities:

— ITU-T V.92*: 56000 bits/s—28000 bits/s

— ITU-T V.90*: 56000 bits/s—28000 bits/s

— ITU-T V.34: 33600 bits/s—2400 bits/s

— V.32bis, and fallbacks

— V.42 and MNP ? error correction (LAPM)

— V.44, V.42bis and MNP Class 5 data compression

■ FAX mode capabilities:

— ITU-T V.17, V.29, V.27ter, and V.21 Ch 2

— ITU-T T.31 Class 1 FAX

■ Compatible with transformer-based and silicon DAA circuits:

— High-precision sigma-delta codec (CSP1034C)

— Line-powered silicon DAA (CSP1035A)

■ Enhanced voice features:

— Full-duplex speakerphone (requires CSP1027 audio codec)

— Telephone answering machine (TAM)

— Caller identification (caller-ID)

■ V.80 video-ready interface

■ Bit I/Os to support domestic and international DAAs

■ Low power consumption

■ Flexible power management modes

■ Operating system support:

— Windows ? 95, 98, 2000, Windows NT ? 4.0, Windows ME, and Windows XP

— Linux ?

— PC 2001 compliant