IBIS file question for AM3703 CUS package

AM,

Usually the selectors in a pin options relate to the configurable modes of the specific pin.

For example, if a pin has multiple drive strengths which are selectable through pin configurations then each drive strength will have a selector in the list.

The correct selector to use therefore would depend on how the specific pin is configured in your particular application.

The same is true for input loading characteristics such as pull up (PU), pull down (PD) and pull inhibited (PI).

In some models the input and output sub-models are also split into 2 separate selectors, so it will depend on whether you are running input simulations or output simulations.

Other selectors may be included for different voltage ranges, such as +- 5% & +-10%, or in some case +-0.1V etc...

BR,

Steve

Hi Steve,

Your explanation makes sense, there is just a few additional parameters I wasn't quite sure how to associate. A few examples from the IBIS file:

Model15 1.8V-I/O-PD-SC01LB10-1.8 +5/-10%

A number of the models use what appears to be binary digits after "SC" and "LB" prefixes. In some cases SC and LB are followed by a single 0 or 1.

Model109 1.8V-I/O-PU-DS1-1.8V +5/-10%

A few of the models also use a "DS" prefix. Would you be able to shed some light on what the SC, LB and DS prefixes represent? Also, what are the digits following these prefixes associated with? Do they match up to IO configuration register bits described in the technical reference manual?

Thanks in advance - AM

One issue with the way that the IBIS models are generated is that the IO cells may be build from cells which have many more programmable options than are exposed and/or configured for a particular device and/or pin, so there is often nomenclature like this which can be confusing since these labels often are more relevant to the IO cell structure and not to the specific device or pin.

Having said this if the pin does have programmable options then there is usually a reasonably obvious correlation between the nomenclature and the data sheet/TRM for the particular pin. In this case DS most likely corresponds to drive strength, which should be documented in the TRM etc...

Now, there are possibly cases where the mapping is not very obvious, and there may also be cases where either options exist where they should probably not, or visa-versa. In these situations we would certainly appreciate your feedback and comments so that we might make the models clearer and less confusing/incorrect.

In the above example DS corresponds to drive strength and SR corresponds to slew rate I believe. I am not 100% sure about LB.

BR,

Steve