[SI-LIST] Re: Problem with Cypress CY7C65640 USB Hub IBIS model
- From: Joel Brown <joel@xxxxxxxxxx>
- To: weston.beal@xxxxxxxxx
- Date: Fri, 10 Mar 2006 13:03:57 -0800
Weston,
That seems to have fixed the problem.
My simulation looks reasonable now.
Is there an IBIS for Dummies book I should read, so I can troubleshoot
these problems myself?
Thanks - Joel
Beal, Weston wrote:
> Tom,
>
> I believe that the model in question is the bp_usb_hs which has two
> rising and two falling waveforms. While this model has a couple of small
> problems, I don't see anything from just looking at the text that should
> cause a problem.=20
>
> Joel,
> I think that the problem is the circuit that you are simulating. Notice
> that the buffer model has essentially 0 current in the normal operating
> range. Without some resistance across the differential pair, the
> simulator probably can't get the correct initial DC operating point. Try
> putting a 90 Ohm resistor across the receiver pins in your simulation
> circuit.
>
> Later,
> Weston
>
>
> -----Original Message-----
> From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]
> On Behalf Of Tom Dagostino
> Sent: Friday, March 10, 2006 12:08 PM
> To: joel@xxxxxxxxxx; si-list@xxxxxxxxxxxxx
> Subject: [SI-LIST] Re: Problem with Cypress CY7C65640 USB Hub IBIS model
>
> Joel
>
> This model has only the rising and falling waveforms with the load
> terminated to Vcc. Without the rising and falling waveforms to ground
> it
> will not simulate correctly.
>
> Tom Dagostino
> Teraspeed(R) Labs
> 13610 SW Harness Lane
> Beaverton, OR 97008
> 503-430-1065
> tom@xxxxxxxxxxxxx
> www.teraspeed.com
>
> Teraspeed Consulting Group LLC
> 121 North River Drive
> Narragansett, RI 02882
> 401-284-1827
>
> -----Original Message-----
> From: si-list-bounce@xxxxxxxxxxxxx
> [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Joel Brown
> Sent: Friday, March 10, 2006 11:46 AM
> To: si-list@xxxxxxxxxxxxx
> Subject: [SI-LIST] Problem with Cypress CY7C65640 USB Hub IBIS model
>
>
> Has anybody used the Cypress CY7C65640 USB Hub IBIS model?
> I seem to having problems with it when simulating in Hyperlynx.
> First of all the part has 5 USB ports on it, but Cypress only defined
> one port as differential.
> So when I try to select a diff pair in Hyperlynx only one side of the
> pair gets selected.
> I was able to correct this by editing the IBIS file and adding Diff Pin
> statements to define the other 4 USB ports as differential.
> When I simulate with the CY7C65640 driving the USB lines and use 45 ohm
> termination to ground at the connector end of the lines then everything
> looks good. If I use the CY7C65640 in receive mode to terminate instead
> of the 45 ohm resistors then it looks bad. It seem that something is
> wrong with this model when used as a receiver. If you want to see the
> model it is located on Cypress web site at:
> http://www.cypress.com/portal/server.pt?space=3DCommunityPage&control=3DS=
> etC
> ommu
> nity&CommunityID=3D209&PageID=3D418&r_folder=3DModels&r_title=3DCY7C65640=
> -Ibis
>
> I have tried using Cypress tech support in the past and it was a
> disaster. You can't talk to anybody they have some web based system that
> takes days to get an answer and usually the answer you get is useless. I
> tried looking for some other USB transceiver IBIS model to try but have
> not been able to find one.
>
> Thanks - Joel
>
>
>
> -- Binary/unsupported file stripped by Ecartis --
> -- Type: text/x-vcard
> -- File: joel.vcf
>
>
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
> List FAQ wiki page is located at:
> http://si-list.org/wiki/wiki.pl?Si-List_FAQ
>
> List technical documents are available at:
> http://www.si-list.org
>
> List archives are viewable at:
> //www.freelists.org/archives/si-list
> or at our remote archives:
> http://groups.yahoo.com/group/si-list/messages
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
>
>
>
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
> List FAQ wiki page is located at:
> http://si-list.org/wiki/wiki.pl?Si-List_FAQ
>
> List technical documents are available at:
> http://www.si-list.org
>
> List archives are viewable at: =20
> //www.freelists.org/archives/si-list
> or at our remote archives:
> http://groups.yahoo.com/group/si-list/messages
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
> =20
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
> List FAQ wiki page is located at:
> http://si-list.org/wiki/wiki.pl?Si-List_FAQ
>
> List technical documents are available at:
> http://www.si-list.org
>
> List archives are viewable at:
> //www.freelists.org/archives/si-list
> or at our remote archives:
> http://groups.yahoo.com/group/si-list/messages
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
>
>
>
>
-- Binary/unsupported file stripped by Ecartis --
-- Type: text/x-vcard
-- File: joel.vcf
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
