[ibis-macro] Re: A new IBIS 5.1 Issue
- From: Mike LaBonte <mike@xxxxxxxxxxx>
- To: IBIS-ATM <ibis-macro@xxxxxxxxxxxxx>
- Date: Mon, 19 Sep 2011 17:26:07 -0400
I think EDA tools use Model_type mainly to decide whether to try to
stimulate it, interpret received signals at it, or neither of the above. A
Terminator model's I/V curves will affect the simulation, but the EDA tool
might not measure any data at it's terminals. It really should be used for
dedicated terminator pins that might have somewhat complex curves.
An AMI model is always called "the TX' or 'the RX', so I can't see them ever
serving us just a terminator. The analog portion of an RX AMI model might
serve to terminate, but ignoring the DLL returns seems like a waste of
resources.
Mike
On Mon, Sep 19, 2011 at 5:06 PM, Tom Dagostino <tom@xxxxxxxxxxxxx> wrote:
> Walter****
>
> ** **
>
> A terminator model can have from a very low impedance to an infinite
> impedance to ground (or a voltage). When using the Bus Switch model in IBIS
> the pins are assigned a terminator model and the bus switch model is picked
> up in the series model section. The kind of IC that I am contemplating is
> my question would have two or more differential inputs routed to a single
> differential output pin or used in the opposite direction, one input and
> multiple outputs. These are available now for many applications. I’ve
> worked with several for HDMI/DVI applications. A typical application could
> be multiple DVI inputs on a display feeding a single receiver in the
> display.****
>
> ** **
>
> So, my question is would forbidding a Terminator model at the receiver
> disallow a bus switch at the receive end?****
>
> ** **
>
> Tom Dagostino****
>
> ** **
>
> Teraspeed Labs****
>
> 9999 SW Wilshire St.****
>
> Suite 102****
>
> Portland, OR 97225****
>
> USA****
>
> ** **
>
> 971-279-5325 Office****
>
> 971-279-5326 FAX****
>
> 503-430-1065 Cell****
>
> ** **
>
> tom@xxxxxxxxxxxxx ****
>
> www.teraspeed.com ****
>
> ** **
>
> Teraspeed Consulting Group LLC****
>
> 121 North River Drive****
>
> Narragansett, RI 02882****
>
> 401-284-1827****
>
> ** **
>
> *From:* ibis-macro-bounce@xxxxxxxxxxxxx [mailto:
> ibis-macro-bounce@xxxxxxxxxxxxx] *On Behalf Of *Walter Katz
> *Sent:* Monday, September 19, 2011 1:40 PM
> *To:* tom@xxxxxxxxxxxxx; 'IBIS-ATM'
> *Subject:* [ibis-macro] Re: A new IBIS 5.1 Issue****
>
> ** **
>
> Tom,****
>
> ** **
>
> A Terminator is something that goes to ground (or a voltage). An AMI “Bus
> Switch” would have both a differential input and a differential output. I
> assume you mean by a buss switch something that had one differential input
> and multiple differential outputs, or one differential output and multiple
> differential inputs. The Repeater BIRD that I introduced to IBIS (BIRD 131).
> Is a “Bus Switch” with one input and one output.****
>
> ** **
>
> Walter****
>
> ** **
>
> *From:* Tom Dagostino [mailto:tom@xxxxxxxxxxxxx]
> *Sent:* Monday, September 19, 2011 4:26 PM
> *To:* wkatz@xxxxxxxxxx; 'IBIS-ATM'
> *Subject:* RE: [ibis-macro] A new IBIS 5.1 Issue****
>
> ** **
>
> Walter****
>
> ** **
>
> Would prohibiting Terminator disallow a Bus Switch in the path?****
>
> ** **
>
> Tom Dagostino****
>
> ** **
>
> Teraspeed Labs****
>
> 9999 SW Wilshire St.****
>
> Suite 102****
>
> Portland, OR 97225****
>
> USA****
>
> ** **
>
> 971-279-5325 Office****
>
> 971-279-5326 FAX****
>
> 503-430-1065 Cell****
>
> ** **
>
> tom@xxxxxxxxxxxxx ****
>
> www.teraspeed.com ****
>
> ** **
>
> Teraspeed Consulting Group LLC****
>
> 121 North River Drive****
>
> Narragansett, RI 02882****
>
> 401-284-1827****
>
> ** **
>
> *From:* ibis-macro-bounce@xxxxxxxxxxxxx
> [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] *On Behalf Of *Walter Katz
> *Sent:* Monday, September 19, 2011 11:27 AM
> *To:* IBIS-ATM
> *Subject:* [ibis-macro] A new IBIS 5.1 Issue****
>
> ** **
>
> All,****
>
> ** **
>
> We have received an IBIS file with an AMI Rx that has Model_type
> Terminator.****
>
> ** **
>
> It was always my understanding that an AMI Tx [Model] would be Model_Type
> Output (or Output_diff), and an AMI Rx [Model] would be Model_Type Input (or
> Input_diff).****
>
> ** **
>
> IBIS 5.0 is not clear on this. Would you like a BIRD for 5.1 that
> explicitly says that Model_type Terminator is allowed or not permitted for
> AMI Rx [Model]s?****
>
> ** **
>
> Walter****
>
> ** **
>
> ** **
>
> Walter Katz****
>
> wkatz@xxxxxxxxxx****
>
> Phone 303.449-2308****
>
> Mobile 720.333-1107****
>
> ** **
>
Other related posts:
