ICS1893 Data Sheet - Release
Chapter 3 ICS1893 Enhanced Features
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
ICS1893 PHY address from
Table 8-16,
which minimizes crosstalk and noise in repeater applications.
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.
summarizes the differences between the ICS1890 and the ICS1893
Management Registers.
ICS1893 Rev B 9/10/99
Copyright © 1999, Integrated Circuit Systems, Inc.
All rights reserved.
14
September, 1999
ICS [ INTEGRATED CIRCUIT SYSTEMS ]
