ICS1893 Rev B 9/10/99

September, 1999

14

Chapter 3

ICS1893 Enhanced Features

ICS1893 Data Sheet - Release

Copyright © 1999, Integrated Circuit Systems, Inc.

All rights reserved.

Chapter 3

ICS1893 Enhanced Features

The ICS1893 is an enhanced version of the ICS1890. In contrast to the ICS1890, the ICS1893 offers

significant improvements in both performance and features while maintaining backward compatibility. The

specific differences between these devices are listed below.

1.

The ICS1893 employs an advanced digital signal processing (DSP) architecture that improves the

100Base-TX Receiver performance beyond that of any other PHY in the market. Specifically:

a. The ICS1893 DSP-based, adaptive equalization process allows the ICS1893 to accommodate a

maximum cable attenuation/insertion loss in excess of 24 dB, which is nearly equivalent to the

attenuation loss of a 100-meter Category 5 cable.

b. The ICS1893 DSP-based, baseline-wander correction process eliminates killer packets.

2.

The analog 10Base-T Receive Phase-Locked Loop (PLL) of the ICS1890 is replaced with a digital PLL

in the ICS1893, thereby resulting in lower jitter and improved stability.

3.

The ICS1890 Frequency-Locked Loop (FLL) that is part of the 100Base-TX Clock and Data Recovery

circuitry is replaced with a digital FLL in the ICS1893, also resulting in lower jitter and improved stability.

4.

The ICS1893 transmit circuits are improved in contrast to the ICS1890, resulting in a decrease in the

magnitude of the 10Base-T harmonic content generated during transmission. (See ISO/IEC 8802-3:

1993 clause 8.3.1.3.)

5.

The ICS1893 supports the Auto-Negotiation Next Page functions described in IEEE Std 802.3u-1995

clause 28.2.3.4.

6.

The ICS1893 supports Management Frame (MF) Preamble Suppression.

7.

The ICS1893 provides the Remote Jabber capability.

8.

The ICS1893 has an improved version of the ICS1890 10Base-T Squelch operation.

9.

The ICS1893 “seeds” (that is, initializes) the Transmit Stream Cipher Shift register by using the

10. The ICS1893 offers an automatic 10Base-T power-down mode.

11. The enhanced features of the ICS1893 required some modifications to the ICS1890 Management

Registers. However, the ICS1893 Management Registers are backward-compatible with the ICS1890

Management Registers. Table 3-1 summarizes the differences between the ICS1890 and the ICS1893

Management Registers.