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DDRx IBIS file has full and half models- what's the difference?

Question asked by user987654321 on Sep 4, 2020
Latest reply on Sep 9, 2020 by user987654321

The IBIS file for this part has "Full" and "Half" Models for the data and strobe pins. Comparing the two models, the currents in the Full models are roughly double that of the corresponding Half model. The ramp rates are also faster in the Full models. This is new to me - from what I was able to find it looks like this refers to the termination: full means parallel termination at both the driver and receiver, and half means parallel termination at the receiver. Is that correct?

 

If that assumption is accurate, how do I determine which to use? Do I look at the controller IBIS file to see if it uses ODT, and/or if there is an external termination resistor at the driver?

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