Hello Shulong:
You are correct. However, I recommend that you delay implementing this
part of IBIS Version 4.1. Even the pending IBIS parser will flag this
disconnect as an Error. So I would wait for a formal solution per
the comments below.
Regards,
Bob
slwu wrote:
> Hi Bob,
>
> I think EDA tool may not know which die pad is connected to a certain pin,
> so it seems impossible for EDA tool to construct such a connection
> automatically.
Correct.
> However, if such connections are provided by model users in his circuit netlist
> directly,
> then EDA tools can construct the connection as the model users expect.
> Is my understanding right ?
In theory, yes. However, at this time I would simply avoid adding such
a connection capability and wait for the IBIS Committee to propose
a solution for Version 4.2 with the appropriate new syntax.
>
> Thanks very much
> Shulong
>
> Bob Ross wrote:
>
>
>>Hello Shulong:
>>
>>In IBIS Version 4.1, there is no direct method to connect the
>>die pads to pins listed below. As you discovered, there is no
>>reference through [Circuit Call]s for such a connection. So at
>>this time the EDA tool would have to provide the connection outside
>>of the IBIS syntax.
>>
>>However, solutions are being discussed and should lead to a
>>proposal for IBIS Version 4.2. The proposals will probably involve
>>some linkage syntax involving IBIS and the Interconnect Model Specification
>>(ICM) for a more general package model.
>>
>>Regards,
>>Bob
>>
>>slwu wrote:
>>
>>
>>>Hi,
>>>
>>>I am still not very clear...so giving an exact example may be more
>>>understood for me.
>>>In the diagram on Page 112 of the IBIS 4.1 specification, there are several
>>>
>>>connections between die pads and pins that I can not understand how they
>>>are constructed through [Circuit Call]s on Page 113~114
>>>1. "pad_11" <====> "11"
>>>2. "pad_2a"/"pad_2b" <====> "2"
>>>3. "pad_4" <===> "4a" /"4b"
>>>
>>>Thanks very much
>>>slwu
>>>
-- Bob Ross Teraspeed Consulting Group LLC Teraspeed Labs 121 North River Drive 13610 SW Harness Lane Narragansett, RI 02882 Beaverton, OR 97008 503-750-6481 503-430-1065 http://www.teraspeed.com 503-246-8048 Direct bob@teraspeed.com |------------------------------------------------------------------ |For help or to subscribe/unsubscribe, email majordomo@eda.org |with just the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or email a written request to ibis-request@eda.org. | |IBIS reflector archives exist under: | | http://www.eda.org/pub/ibis/email_archive/ Recent | http://www.eda.org/pub/ibis/users_archive/ Recent | http://www.eda.org/pub/ibis/email/ E-mail since 1993Received on Wed Nov 10 18:59:34 2004
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