Subject: Re: [IBIS-Users] (lv)pecl
From: erik.van.der.ven@philips.com
Date: Mon May 12 2003 - 01:44:14 PDT
Dear Fred,
Thank you for your reply. About the garbage; I explained it in an email I
just sent (directed to Tom).
The s2ibis program does not generate IV- tables from 0-2.2V, but the
program that has been modified by my collegue does do this (apart from the
"garbage" that both programs produce).
Is this range enough? According to Tom it should be -3.3-6.6V. Where is
this range for ECL/PECL defined? I cannot find it in the specification.
When the voltage is out of the normal operating range the currents can be
very high, even so high that the transistor models are not valid anymore.
What is the use of specifying these currents? Can they be left out? If
not, what is done with this information.
I have the same question for the clamp currents. The output can be
disabled, so this is a kind of tri-state (not really high impedant). Also
here the currents are unrealistically high. What is done with this
information? Why must it be specified? The PECL voltage swing is such that
even a fully reflected signal will not cause the output to be outside the
supply range.
With kind regards,
Ir. Erik van der Ven
Room DB1032
Business Line Networking Infrastructure
Philips Semiconductors BV
Gerstweg 2
6534 AE Nijmegen
The Netherlands
Phone: +31-24-3534334
Fred Balistreri <fred@apsimtech.com>
Sent by:
fred@interjet.apsimtech.com
05/09/03 07:10 PM
To: Erik van der Ven/NYM/SC/PHILIPS@EMEA2
cc:
Subject: Re: [IBIS-Users] (lv)pecl
Classification:
Erik, you need to define what convention you are
using when you say voltage range. Remember that
for ECL and PECL both the pullup and pulldown
reference is the same. If the voltage range
you refer to is the IBIS Vtable then your
range is not correct. Under the IBIS conventions
for ECL or PECL type Vtable= Vcc - Vout.
This is true for both pullup/pulldown for PECL/ECL.
IBIS further explains that for ECL, PECL the
range should be VCC - 2.2 volts. Under the
IBIS rules then the range should always be
0 - 2.2 volts for both pullup and pulldown.
Note that 0 really means 3.3 at the output
for your case and 2.2 really means 1.1 at the
output.
I don't quite understand your problem. You state
garbage. It's probably not quite descriptive
enough to understand your issue. Although the
meaning is clear.
Best Regards,
erik.van.der.ven@philips.com wrote:
>
> Part 1.1Type: Plain Text (text/plain)
-- Fred Balistreri fred@apsimtech.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 1993
This archive was generated by hypermail 2b28 : Mon May 12 2003 - 01:53:14 PDT