Ctm is doing signal Integrity simulations on the QSPI-If of our LS1046A design.
They are using the IBIS model ‘ls1046_vop3_9april2016.ibs’
For the QSPI-IF I found the models ‘lvcmos18_ssr_fc_out’ or ‘lvcmos18_fsr_fc_out’ for output pins and ‘lvcmos18_fsr_fc_io’ or ‘lvcmos18_ssr_fc_io’ for I/O-pins.
They haven’t found a possibility to select between one of the two I/O characteristics in the Reference Manual nor in the Datasheet.
Question:
Is there a possibility to select between the different driving strengths or it is fixed?
If fixed, which one is used?
The IBIS model you are using is not most recent and indeed contains model selector "lvcmos" for these pins.Your understanding is correct, impedance is fixed and, therefore, this model selector is not necessary. For QSPI pins actual model will be model with *fsr* suffix.
Please submit a ticket to online technical support to get most recent IBIS model, which does not have this problem.
How to submit a new question for NXP Support
Have a great day,
Alexander
TIC
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