Re: Clarification needed.

Anbazhagan,

Looks like you're on the right track. I would recommend your ASIC vendor
read the "IBIS Cookbook," which can be found on the IBIS web page:
http://www.eigroup.org/ibis/tools.htm

As part of the "I/O Buffer Accuracy Handbook" (also available on the IBIS
web page), we published a checklist that should help you. This list was
compiled from suggestions by members of the SI community who have
experience with IBIS. I am attaching the most recent version of this list.

Bob, Could you please post this list as an ASCII text file under Accuracy?
Pleas name it "checklist.txt." Thanks.

IBIS Datasheet Checklist version 1.1,
05/07/01
------------------------

IBIS datasheet:
Component manufacturer:
Component part number:
Engineer verifying this component:
Email address:
Behavioral simulator and version:
Date:

Note: If answer is N or N/A, provide explanation.
        The user may verify items 1-9 but is unable to verify items 10-20
        because the data involved are only available to the semiconductor
        vendor.

___ 1. Does the IBIS datasheet pass the IBIS syntax checker?
        (Note: Some models generate warnings for non-monotonicities that
are
        actually part of the characteristics of the device. Other non-
        monotonicities are so small as to be irrelevant.)

___ 2. Is an "I/O Buffer Accuracy Report" available for this component?
        (http://www.vhdl.org/pub/ibis/accuracy)

___ 3. Has the modeling engineer performed a visual inspection of IV and
VT
        curves to screen for non-monotonicity, discontinuities, and other
        obvious errors?

___ 4. Has the modeling engineer tested the IBIS datasheet using a
behavioral
        simulator?

___ 5. Do MIN and MAX data exist for all keywords and sub-parameters?

___ 6. Does the IBIS datasheet include all four 50 Ohm VT tables as
described
        in the IBIS Cookbook?

___ 7. Do the keywords Cref, Rref, Vref, and Vmeas match the values
specified
        in the component datasheet for all output and bidirectional models?

___ 8. Does the output reach Vmeas under standard load conditions for
rising
        and falling waveforms?

___ 9. Does the pin table match the component datasheet?

___ 10. Do the keywords Vihl and Vinh represent the unity gain points
derived
        from the dc transfer characteristics for all inputs?

___ 11. Has the modeling engineer verified the accuracy of the C_comp
        subparameter?

___ 12. Has the modeling engineer verified the accuracy of the R_pkg,
L_pkg,
        and C_pkg subparameters?

___ 13. For CMOS logic, do all MAX data represent maximum voltage, minimum
        temperature, and fast process?

___ 14. For CMOS logic, do all MIN data represent minimum voltage, maximum
        temperature, and slow process?

___ 15. For bipolar logic, do all MAX data represent maximum voltage,
maximum
        temperature, and fast process?

___ 16. For bipolar logic, do all MIN data represent minimum voltage,
minimum
        temperature, and slow process?

___ 17. Do the keywords dV/dt_r and dV/dt_f contain the correct 20%-80%
edge
        rate data measured using a 50 & load as specified in IBIS?

___ 18. If the I/O buffer employs dynamic clamping, does the IBIS datasheet
        contain the appropriate keywords and subparameters?

___ 19. If the I/O buffer employs a multi-stage driver, does the IBIS
datasheet
        contain the appropriate keywords and subparameters?

___ 20. If the I/O buffer design employs dynamic edge rate control, dynamic
        impedance control, or any form of feedback, has the modeling
engineer
        assessed the impact of this circuitry on behavioral model accuracy?

Greg Edlund
Electrical Packaging
IBM Server Technology Development
3605 Hwy. 52 N, Dept. HDC
Rochester, MN 55901
gedlund@us.ibm.com

Anbu@scmmicro.co.in on 05/24/2001 01:48:13 AM

To: "ibis-users@eda.org":
cc:
Subject: Clarification needed.

Hello Users,

        I am using XTK to simulate a PCBA. The board has a 100pin ASIC. In
order to model the ASIC properly I need the IBIS model of the ASIC which I
can convert it to XTK format. Now if I directly request for an IBIS model
the vendor may hesistate. So I am requesting the following data from the
vendor with which I can create a IBIS model. Below is the data I am
requesting them. Is it OK. Does it cover everything necessary to create a
proper IBIS model?. The ASIC does not have any clamp diodes. Please reply.
The following data whichever is applicable for each pin of the ASIC are
needed
 1. Package parasitics namely, the Resistance, capacitance and Inductance.
Typical, max, min values required.

2. Die capacitance as seen at the die pad. Typical, max, min values
required

3. Output impedance of the I/O buffers. Typical, max, min values required.

4. Rise time and fall time values (dv/dt typical, max, min) of buffers
excluding the effect of packaging but including the effect of die
capacitance. Load conditions required.

6. Rising edge and falling edge waveforms (Voltage vs. time curve with the
voltage values having typical, max, min values) of the driver along with
the test conditions.

5. V/I characteristics of Pull up and Pull down resistor, if present, when
the buffer is driven high and low respectively. The voltage sweep must be
from ?3.3V to +6.6V. Current measurement with typical, max, min values are
required.

Thanks,

Anbazhagan.

 
Received on Thu May 24 18:05:13 2001