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DXX.X

K28.5

DXX.X

DXX.X

K28.5

K28.5

DXX.X

DXX.X

DXX.X

DXX.X

DXX.X

K28.5

DXX.X

DXX.X

K28.5

K28.5

DXX.X

DXX.X

31 Bit

Times

Max Receive

Path Latency

Worst Case

Misaligned K28.5

Misalignment Corrected

INPUT DATA

RBC0

RBC1

RD(0-9)

SYNC

Corrupt Data

30 Bit

Times (Max)

Data Reception Latency

10 Bit Code

RXP, RXN

RD(0-9)

RBC0

10 Bit Code

Loss of Signal Detection

TLK2201

TLK2201I

ETHERNET TRANSCEIVERS

SLLS420F – JUNE 2000 – REVISED SEPTEMBER 2007

Figure 5. Word Realignment Timing Characteristics Waveforms

Systems that do not require framed data may disable byte alignment by tying SYNCEN low.

When a SYNC character is detected, the SYNC signal is brought high and is aligned with the K28.5 character.

The duration of the SYNC pulse is equal to the duration of the data when in TBI mode. When in DDR mode the

SYNC pulse is present for the entire RBC0 period.

The serial to parallel data latency is the time from when the first bit arrives at the receiver until it is output in the

aligned parallel word with RD0 received as first bit. The minimum latency in TBI mode is 21 bit times and the

maximum latency is 31 bit times. The minimum latency in DDR mode is 27 bit times and maximum latency is 34

bit times.

Figure 6. Receiver Latency - TBI Normal Mode Shown

These devices have a loss of signal (LOS) detection circuit for conditions where the incoming signal no longer

has sufficient voltage level to keep the clock recovery circuit in lock. The LOS is intended to be an indication of

gross signal error conditions, such as a detached cable or no signal being transmitted, and not an indication of

signal coding health. Under a PRBS serial input pattern, LOS is high for signal amplitudes greater than 150 mV.

The LOS is low for all amplitudes below 50 mV. Between 50 mV and 150 mV, LOS is undetermined.

8

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