IBIS Model Acronym Definitions

[wleismer]

Hello, I am working with the LPC54Sxx IBIS model, and it is unclear to me which models are intended to be used to confirm signal integrity as a pin outputs to a transmission line.  For example, there are two main models, MFIOHST5V_3V3_XX_ZZ and MFIOT5V_3V3_XX_ZZ

Where: XX can be PU,PD,RP,ZS and ZZ can be HS or LS.

I understand that PU = Pull Up, PD = Pull Down, but what does RP = ? and ZS = ? (I'm guessing high impedance?).  Is HS = High Speed and LS = Low Speed?

If I want to model the effects on signal integrity from PIO0_16 (ball M4 on the 180 pin BGA), which is Ethernet TXD_0 Out, which model should I use?

Here is the LPC54Sxx page, where the datasheet and IBIS model are located: https://www.nxp.com/part/LPC54S016JBD100#/

[wleismer]

I was able to confirm some of my questions using the IBIS Modeling Cookbook.  In it, it states that each model can be for Input, Output, or I/O, so that is clear to me now. It is also clear that the PU model is to be used for output driving high, and the PD model is to be used for output driving low.  What remains unclear is the following:

RP means ?

ZS means?

HS means?

LS means?

[Alice_Yang]

Hello wleismer,

I will help to confirm with design team. then tell you .ASAP.

BR

Alice

[wleismer]

Thanks Alice!

[Alice_Yang · Accepted solution]

Hello wleismer,

>>>> The definitions are below and can be controlled via IOCON register.

Hs – slew rate is fast mode

Ls – slew rate is standard mode

Rp – simulated open drain mode enabled

PU means internal pull-up enabled

PD means internal pull-down enabled

ZS – disable internal pull-up and disable internal pull-down

Use the MFIOT5V model since pad type for PIO0_16 is MFIOT5V

BR

Alice

[wleismer]

Excellent, thank you so much Alice!

[Alice_Yang]

Hello wleismer,

Welcome!

BR

Alice