Inquiry Regarding Cyclone V IBIS Model Definitions and Updates

Dear Farabi,

Thank you for your response and for taking over the case.

I would like to clarify a mistake in my initial message. The model pairs I intended to refer to were not:

• "lvcmos_rtpio_d2s1" and "lvcmos_rtpio_d16s1"
• "lvcmos_rtpio_d2s1_p" and "lvcmos_rtpio_d16s1_p"

but rather:

• "lvcmos_rtpio_d2s1" and "lvttl_rtpio_d16s1"
• "lvcmos_rtpio_d2s1_p" and "lvttl_rtpio_d16s1_p"

Upon inspecting the cyclone5.ibs file, I found that these pairs have identical IBIS definitions, despite differing in name, I/O standard, and drive strength. This raises concerns about whether the models are correctly differentiated and whether they can be reliably used for signal integrity simulations.

As FvM pointed out in another thread(Re: Inquiry Regarding Cyclone V IBIS Model Definitions and Updates - Intel Community), the I/V curves of "lvcmos_rtpio_d2s1" do not match the expected behavior for 2 mA drive strength, and instead resemble higher current settings. This suggests that there may be inconsistencies or errors in the IBIS model definitions.

Could you please confirm whether this duplication is intentional, and if not, whether corrected IBIS models are available?

Thank you again for your support.

Best regards,
Ryusuke YOKOYA