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Associate II
September 16, 2023
Question

STM32747IGT6 IBIS Model Issues

  • September 16, 2023
  • 2 replies
  • 5273 views

Hi, 

We are trying to run a signal integrity simulation of STM32H747IGT6 in Altium Designer. However, all of the reflection waveforms for signals driven by the device are around 0 volts (basically noise, no driver). We've noticed there is some errata for other IBIS models in this product family. Are there any known issues with this IBIS model? Or can someone recommend a remedy? 

We are using "stm32h747_757_lqfp176.ibs" downloaded from: https://www.st.com/en/microcontrollers-microprocessors/stm32h747ig.html#cad-resources.

Thanks!

2 replies

STOne-32
Technical Moderator
September 16, 2023

Dear @slc2015,

I’m not expert in Altium Signal integrity simulation features inside the tool, may be you can go to Altium Community to find help .

I confirm that the model from our side is working with Hyperlynx : here is attached our application note - go to section 5.2 for STM32F7 example https://www.st.com/resource/en/application_note/an4803-highspeed-si-simulations-using-ibis-and-boardlevel-simulations-using-hyperlynx-si-on-stm32-mcus-and-mpus-stmicroelectronics.pdf

In our model for this MCU, the Package model might be not included separately and is already embedded. 
Is that possible to show some screenshots on the tool ? To assist you more .

ciao

STOne-32

 

 

 

slc2015Author
Associate II
September 18, 2023

Hi,

Here is a screenshot of the waveform with the model from ST. 

Thanks!image.png

STOne-32
Technical Moderator
September 19, 2023

Dear @slc2015 

Indeed , it seems only Noise.   

The Signal Integrity Analysis capabilities are available through an Altium Designer Signal Integrity Analysis system extension, which is not installed with Altium Designer by default.

I believe we need to engage discussion with Altium partner to see how to configure our IBIS model with Altium IBIS model readers, It may happen not compatible with the IBIS versions that we need to check.

Have a good day,

STOne-32

Visitor II
January 24, 2024

I'm trying to perform signal integrity analysis in Altium too, but for STM32G474MET. I'm using the official stm32g471_473_474_483_484_lqfp80.ibs and I see very similar results on simulation, everything is just noise and no signal. Also for this package there is an extra pin 0 - GND, which is not existing for this package. The extension is already licensed and installed on the latest AD24 platform. The error occurs only when the MCU is the driver. When the MCU is defined as input I can see results (however I still couldn't validate the signals as the PCB is not realized yet.).
Schematic:

LewisBristle_2-1706094662799.png

 


Driver MCU, receiver: 74LXC8T245
LewisBristle_0-1706093990793.png

 

Driver: 74LXC8T245, Receiver: MCU

LewisBristle_1-1706094315776.png

 

The pictures above are from a synthetic test project, that's why the pulse is so ringing.