ICS1892 Datasheet, PDF (53/148 Pages) Integrated Circuit Systems – 10Base-T/100Base-TX Integrated PHYceiver

ICS1892
Chapter 7 Functional Blocks
7.5.11 10Base-T Operation: Twisted-Pair Transmitter
For both 10Base-T and 100Base-TX operations, the ICS1892 uses the same Twisted-Pair Transmit pins
(TP_TXP and TP_TXN) as well as the same internal functional module. The twisted-pair transmitter
module is a current-driven, differential driver that can supply either of the following:
• A two-level 10Base-T (that is, Manchester-encoded) signal
• A three-level 100Base-TX (that is, MLT-3 encoded) signal
The ICS1892 interfaces with the medium through an isolation transformer. The ICS1892 transmitter uses
wave-shaping techniques to control the output signal rise and fall times (thereby eliminating the need for
expensive external filters) and interfaces directly to the isolation transformer.
Note:
1. In reference to the ICS1892, the term ‘Twisted-Pair Transmitter’ refers to the set of Twisted-Pair
Transmit output pins (TP_TXP and TP_TXN).
2. For information on the 100Base-TX Twisted-Pair Transmitter, see Section 7.4.5, “100Base-TX
Operation: Twisted-Pair Transmitter”.
7.5.12 10Base-T Operation: Twisted-Pair Receiver
Twisted-Pair Receiver operations are similar to Twister-Pair Transmitter operations, in that for both
10Base-T and 100Base-TX operations, the ICS1892 uses the same Twister-Pair Receive pins (TP_RXP
and TP_RXN).
However, unlike the transmitter operations (which use the same internal functional module), the ICS1892
employs separate internal twisted-pair receiver modules to process the incoming data: one for 10Base-T
operations and one for 100Base-TX operations. The internal twisted-pair receiver modules interface with
the medium through an isolation transformer. The 10Base-T receiver module accepts and processes a
differential two-level 10Base-T (that is, Manchester-encoded) signal from the isolation transformer.
Note:
1. In reference to the ICS1892, the term ‘Twisted-Pair Receiver’ refers to the set of Twisted-Pair Receive
output pins (TP_RXP and TP_RXN).
2. For information on the 100Base-TX Twisted-Pair Receiver, see Section 7.4.6, “100Base-TX Operation:
Twisted-Pair Receiver”.
ICS1892, Rev. D, 2/26/01
© 2000-2001, Integrated Circuit Systems, Inc.
All rights reserved.
53
February 26, 2001