1893AFLF IDT, 1893AFLF Datasheet - Page 48

• Manufacturer Part Number: 1893AFLF
• Description: Ethernet ICs 3.3V 10/100 BASE TX INTEGRATED PHYCEIVER
• Manufacturer: IDT
• Type: Integrated PHY Transceiverr

Specifications of 1893AFLF

• Rohs: yes
• Product: Ethernet Transceivers
• Data Rate: 10 Mb/s, 100 Mb/s
• Supply Voltage - Max: 3.47 V
• Supply Voltage - Min: 3.14 V
• Maximum Operating Temperature: + 70 C
• Package / Case: SSOP-48
• Ethernet Connection Type: 100Base-TX, 10Base-T
• Maximum Supply Current: 160 mA
• Minimum Operating Temperature: 0 C
• Standard Supported: 802.3
• Part # Aliases: ICS1893AFLF

7.5.4 10Base-T Operation: Idle
7.5.5 10Base-T Operation: Link Monitor
ICS1893AF, Rev D 10/26/04
An ICS1893AF transmits Normal Link Pulses (that is, 10Base-T Idles) on its MDI in the absence of data (that
is, when the MAC/repeater is not requiring it to transmit any data). During this time the link is Idle, and the
ICS1893AF periodically transmits link pulses at a rate of one link pulse every 16 ms in compliance with the
ISO/IEC 8802-3 standard. In 10Base-T mode, the ICS1893AF continues transmitting link pulses even while
receiving data. This situation does not generate a Collision Detect signal (COL) because link pulses indicate
an idle state for a link.
When an ICS1893AF is in 10Base-T mode, its Link Monitor Function observes the data received by the
10Base-T Twisted-Pair Receiver to determine the link status. The results of this continual monitoring are
stored in the Link Status bit. The Station Management entity (STA) can access the Link Status bit in either
the Status Register (bit 1.2) or the QuickPoll Detailed Status Register (bit 17.0).
When the Link Status bit is:
•
•
The ICS1893AF Link Status bit is a latching low (LL) bit. (For more information on latching high and latching
low bits, see
The criteria used by the Link Monitor Function to declare a link either valid (that is, ‘established’ or ‘up’) or
invalid (that is, ‘failed’ or ‘down’) depends upon these factors: the present state of the link, whether its
Smart Squelch function is enabled, and the incoming data.
When the 10Base-T link is:
•
•
•
Zero, either a valid link is not established or the link is momentarily dropped since either the last read of
the Link Status bit or the last reset of the ICS1893AF.
One, a valid link is established.
Invalid, and the Smart Squelch function is:
Valid, and the Smart Squelch function is:
Valid, the Link Monitor Function declares the link as invalid if it receives neither data nor NLPs (that is,
the link shows either no activity or inconsistent activity) for more than 81 to 83 ms. In this case the Link
Monitor Function sets the Link Status bit to logic zero.
– Disabled (bit 18.0 is logic one), the Link Monitor Function must detect at least one of the following
– Enabled (bit 18.0 is logic zero), the Link Monitor Function must detect at least one of the following
– Disabled (bit 18.0 is logic one), the Link Monitor Function continues to report its link as valid as long
– Enabled (bit 18.0 is logic zero), the Link Monitor Function continues to report its link as valid as long
ICS1893AF Data Sheet - Release
events before transitioning its link from the invalid state to the valid state:
events before transitioning its link from the invalid state to the valid state:
as it continues to detect any of the following:
as it continues to detect any of the following:
• More than seven, ISO/IEC-defined, Normal Link Pulses (NLPs)
• Any valid data
• More than seven, ISO/IEC-defined, Normal Link Pulses (NLPs)
• Any valid data followed by a valid IDL
• ISO/IEC-defined, Normal Link Pulses (NLPs)
• Any valid data
• ISO/IEC-defined, Normal Link Pulses (NLPs)
• Any valid data followed by a valid IDL
Section 8.1.4.1, “Latching High Bits”
Copyright © 2004, Integrated Circuit Systems, Inc.
All rights reserved.
48
and
Section 8.1.4.2, “Latching Low
Chapter 7 Functional Blocks
Bits”.)
October, 2004