Subject: Re: IBIS pin mapping questions

From: Matthew Flora <[email-masked]>
Date: Thu, 17 Dec 1998 08:22:04 -0100

Dear Frank Azema,

> I try to simulate my electronics designs after layout design. I use QUAD
> ANALYZE simulator which include a converter from IBIS model to Quad model to a
> specific part : typ, min or max.
> The logic and physical symbol of the design tools i use are made with the
> specification pin mapping of the manufacturer of the component. In example on
> a microprocessor of Motorola ( the MPC823 microprocessor) the pin mapping is
> an alpha-numeric grid, so i associate the signal name of the data sheet with
> the pin alpha-numeric number in my symbols.
> I found the IBIS model of this microprocessor on the web of Motorola and i try
> to use it. Many errors appeared after converting manipulation to use this
> model. In fact the pin number of the symbol and the pin number of the model
> are different. So the simulator didn't look for the good [model] and the
> simulation gave bad result. So, i correct the pin number mapping and it was
> good for new simulation. 
> 
> In an other design i use the AMD microprocessor AM186er. I ask AMD for IBIS or
> simulation model and their give me the IBIS model AND the Quad model. So, i
> use it and errors appear because the pin number mapping doesn't correct with
> the manufacturer data sheet. Here the pin number mapping in only numeric in
> opposition of the motorola component. 
> 
> MY QUESTION is about the pin number mapping method of a IBIS model. How can i
> found the right method which explain how to make this ? WHY isn't it in phase
> with the data sheet ? i didn't found any application note on the subtract of
> it on your web site.
> My pivot table to correct the pin number mapping is the signal name mapping
> but it isn't every time exactly the same of the data sheet of the
> manufacturer. My contact on different manufacturer can not explain me how the
> ibis model make because it is very big company and the can't find the ibis
> creator. 
> 
> So, are there a method official from IBIS group for this syntax of pin number
> mapping and signal name mapping ? 
> 
> I thank you answer and i give you a merry christmas and a happy new year.
> Frank AZEMA                               ALCATEL BUSINESS SYSTEMS
> Technical direction                       1, route du Dr Albert Schweitzer
> Tel : +33(0)3 88 67 77 00                 F-67408 ILLKIRCH-GRAFFENSTADEN Cedex
> Fax : +33(0)3 88 67 70 83
> <mailto:[email-masked]>

I am forwarding your question to the IBIS Users Group e-mail reflector and
have added you to that reflector so that you will receive any discussions
raised by your question.

If I understand your question correctly, it sounds like the creators of the
IBIS files did not give complete pinouts for the parts.  In my opinion, a
COMPLETE IBIS file lists every pin on the part in the [Pin] section of the
[Component].  If the part is available in multiple packages then the IBIS file
could contain multiple [Component] sections or multiple files may be created.
Furthermore, I believe it silly for the creators of the IBIS files to use pin
and signal names that are inconsistent with the datasheet.  (The IBIS
specification actually requires a full pinout for each [Component] and
specifically says that the pin/signal names should be as given on a
datasheet.)

Regards,

Matthew Flora
IBIS Open Forum Secretary
(425) 869-2320 PH
(425) 881-1008 FAX
[email-masked]
HyperLynx, 17641 NE 67th Court, Redmond, WA 98052 USA

---

From: Syed Huq <[email-masked]>
Date: Thu, 17 Dec 1998 09:43:04 -0800 (PST)

Frank,

I have seen the same issues that you have outlined. Sometimes you get a model
where the [Pin] numbering do not match up with the Datasheet defined numbering.
The Datasheet may have used aplha numerics(eg, BGA pkg) while the [Pin]
columns used sequential numbers.

Unfortunately, I had to fix this myself. The problem goes back to the source
of the IBIS model. They need to be consistent with Datasheet naming convention.
In some cases, the model developer and the Si Manufacturer are two seperate
groups and that could lead to this problem.

It is best you bring this up with your model provider.

Regards,
Syed.
Cisco Systems, Inc

>Frank writes:
> with the data sheet ?