IBIS simulations have shown better results with different IO settings than the one set in Quartus II. How can I apply this result to Quartus II?
Let's take the DDR3 clock as an example.
I set it to dsstl15i_crio_r50s1 in Quartus II and ran compilation. However, in the IBIS simulation, the dsstl15i_crio_d8s1 setting gave the best waveform, so I decided to change the Quartus II setting.
IO model names are named according to the following rules.
| dsstl15i | - Differential 1.5V SSTL Class I | |
| sstl15i | - 1.5V SSTL Class I | |
| crin | - Column input, DIFFIO_RX pin | |
| d8 | - 8mA Current Strength | |
| d6 | - 6mA Current Strength | |
| r50 | - 50 Ohm series on-chip termination without calibration | |
| r50c | - 50 Ohm series on-chip termination with calibration | |
| s1 | -fast Slew Rate |
For example dsstl15i_crio_d8s1 is
| 1) | dsstl15i | - Differential 1.5V SSTL Class I | |
| 2) | sstl15i | - 1.5V SSTL Class I | |
| 3) | d8 | - 8mA Current Strength | |
| 4) | s1 | -fast Slew Rate |
It means that it contains elements of
In Quartus II you have to set
| A) | Differential 1.5V SSTL Class I No change required | |
| B) | Column input and DIFFIO_RX pin are already pinned, so no need to change | |
| C) | Change Current Strength to 8mA | |
| D) | Slew Rate is Default and Fast (set value is 1), so no need to change | |
| E) | Removed the 50 Ohm series on-chip Termination without Calibration setting as the r50 element is gone |
becomes.
Essentially in this example
・ Delete the setting of 50 Ohm series on-chip Termination without Calibration
・ Added setting of 8mA for Current Strength
It will be the work of
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