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BIRD ID#:        131
ISSUE TITLE:     IBIS-AMI Repeaters
REQUESTER:       Walter Katz, Signal Integrity Software, Inc.
DATE SUBMITTED:  April 21, 2011
DATE REVISED:    
DATE ACCEPTED BY IBIS OPEN FORUM: Rejected June 7, 2013

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STATEMENT OF THE ISSUE:

A Differential SerDes Repeater is a four pin model consisting of 
differential SerDes Rx model and a SerDes differential Tx model. Both the Rx 
and Tx models must also contain AMI models. The Rx model may or may not have 
a clock and data recovery loop (CDR). The Rx model may or may not return 
*clock_times. The Rx model AMI_GetWave function output "wave" is used as the 
input to the Tx AMI_GetWave "wave".

This BIRD introduces a new IBIS keyword [Repeater Pin] which associates the 
pins of an Rx model with the pins of a Tx model, thus associating an Rx model 
with a Tx model to form a complete repeater.



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Add to Section 3a  "K E Y W O R D   H I E R A R C H Y" after
|  |     |-- [Diff Pin]                     inv_pin, vdiff, tdelay_typ,
|  |     |                                  tdelay_min, tdelay_max

the following

|  |     |-- [Repeater Pin]                 tx_non_inverting_pin
|  |     |                                 


Add section 5 "C O M P O N E N T    D E S C R I P T I O N" before 
|     Keyword:  [Series Pin Mapping]

the following

|
|=============================================================================
|     Keyword:  [Repeater Pin]
|    Required:  No
| Description:  Associates repeater pins.
|  Sub-Params:  tx_non_inverting_pin
| Usage Rules:  Enter only repeater pin pairs.  The first column, [Repeater
|               Pin] contains a non-inverting pin name of an entry in the
|               [Diff Pin] section that represents an Input model. The 
|               second column, tx_non_inverting_pin contains a non-
|               inverting pin name of an entry in the [Diff Pin] section that
|               represents an Output model corresponding to the Tx part of
|               the Repeater model.
|
| Other Notes:  Each line must contain two columns. 
|               A pin name may appear in only one [Repeater Pin] record. 
|
|-----------------------------------------------------------------------------
[Repeater Pin]  tx_non_inverting_pin
|
 3           11     



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ANALYSIS PATH/DATA THAT LED TO SPECIFICATION

One method to implement high loss SerDes channels is to insert repeaters in 
the channel. A repeater may or may not have a CDR to reconstruct a digital 
waveform. If it has a CDR this device is also known as a Retimer or a 
Regenerator. While existing IBIS keywords are sufficient to specify most 
aspects of a repeater, they define circuit elements that have at most either 
two output pins or two input pins connected to any given analog signal path. 
A differential electrical repeater has two input pins connected to one analog 
signal path and an additional two output pins connected to another analog 
signal path; and these two pairs of pins must be mapped directly to each 
other. The proposed new keyword provides that mapping.


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ANY OTHER BACKGROUND INFORMATION:

This BIRD was rejected during the IBIS Open Forum teleconference of June 7, 
2013, as the content was superseded by the contents of BIRD 156.2.

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