ODT in DDR2+ SRAM IBIS Model

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Anonymous
Not applicable

Hi, the DDR2+ SRAM parts are supposed to have ODT on the DATA lines... but I don't see it in the ibis model.  I see it on the BWS and K/K* though.

   

Example from ddr2pb2l25_cy21xx.ibs (You can see where it says what the driving output impedance is, but the input impedance is unknown):

   

[Model Selector]    DATAIO
|
DATAIO50_TT_1.5   DATAIO models (50ohms) at TT conditions - 1.5V I/O
DATAIO50_FF_1.5   DATAIO models (50ohms) at FF conditions - 1.5V I/O
DATAIO50_TSF_1.5  DATAIO models (50ohms) at Typ Slow Fast conditions- 1.5V I/O
DATAIO30_TT_1.5   DATAIO models (30ohms) at TT conditions - 1.5V I/O
DATAIO30_FF_1.5   DATAIO models (30ohms) at FF conditions - 1.5V I/O
DATAIO30_TSF_1.5  DATAIO models (30ohms) at Typ Slow Fast conditions- 1.5V I/O
DATAIO40_TT_1.5   DATAIO models (40ohms) at TT conditions - 1.5V I/O
DATAIO40_FF_1.5   DATAIO models (40ohms) at FF conditions - 1.5V I/O
DATAIO40_TSF_1.5  DATAIO models (40ohms) at Typ Slow Fast conditions- 1.5V I/O
DATAIO60_TT_1.5   DATAIO models (60ohms) at TT conditions - 1.5V I/O
DATAIO60_FF_1.5   DATAIO models (60ohms) at FF conditions - 1.5V I/O
DATAIO60_TSF_1.5  DATAIO models (60ohms) at Typ Slow Fast conditions- 1.5V I/O
DATAIO70_TT_1.5   DATAIO models (70ohms) at TT conditions - 1.5V I/O
DATAIO70_FF_1.5   DATAIO models (70ohms) at FF conditions - 1.5V I/O

   

Thank you.

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2 Replies
Anonymous
Not applicable

 Hi Westec,

   

          The data inputs also have ODT.Please confirm whether you are referring to the latest IBIS model on the web in link below:

   

http://www.cypress.com/?rID=48344

   

Below are the ODT buffer model in the IBIS model.

   

 

   

 

   

[Model Selector]    INPAD

   

INPUT525_TT_1.5  INPUT models(52.5ohms) at TT conditions - 1.5V I/O 

   

INPUT525_FF_1.5  INPUT models(52.5ohms) at FF conditions - 1.5V I/O 

   

INPUT525_TSF_1.5 INPUT models(52.5ohms) at TypSlowFast conditions- 1.5V I/O

   

INPUT75_TT_1.5   INPUT models (75ohms) at TT conditions - 1.5V I/O 

   

INPUT75_FF_1.5   INPUT models (75ohms) at FF conditions - 1.5V I/O 

   

INPUT75_TSF_1.5  INPUT models (75ohms) at TypSlowFast conditions- 1.5V I/O

   

INPUT90_TT_1.5   INPUT models (90ohms) at TT conditions - 1.5V I/O 

   

INPUT90_FF_1.5   INPUT models (90ohms) at FF conditions - 1.5V I/O 

   

INPUT90_TSF_1.5  INPUT models (90ohms) at TypSlowFast conditions- 1.5V I/O

   

INPUT105_TT_1.5  INPUT models (105ohms) at TT conditions - 1.5V I/O 

   

INPUT105_FF_1.5  INPUT models (105ohms) at FF conditions - 1.5V I/O 

   

INPUT105_TSF_1.5 INPUT models (105ohms) at TypSlowFast conditions- 1.5V I/O

   

INPUT150_TT_1.5  INPUT models (150ohms) at TT conditions - 1.5V I/O 

   

INPUT150_FF_1.5  INPUT models (150ohms) at FF conditions - 1.5V I/O 

   

INPUT150_TSF_1.5 INPUT models (150ohms) at TypSlowFast conditions- 1.5V I/O

   

INPUT525_TT_1.8  INPUT models(52.5ohms) at TT conditions - 1.8V I/O 

   

INPUT525_FF_1.8  INPUT models(52.5ohms) at FF conditions - 1.8V I/O 

   

INPUT525_TSF_1.8 INPUT models(52.5ohms) at TypSlowFast conditions- 1.8V I/O

   

INPUT75_TT_1.8   INPUT models (75ohms) at TT conditions - 1.8V I/O 

   

INPUT75_FF_1.8   INPUT models (75ohms) at FF conditions - 1.8V I/O 

   

INPUT75_TSF_1.8  INPUT models (75ohms) at TypSlowFast conditions- 1.8V I/O

   

INPUT90_TT_1.8   INPUT models (90ohms) at TT conditions - 1.8V I/O 

   

INPUT90_FF_1.8   INPUT models (90ohms) at FF conditions - 1.8V I/O 

   

INPUT90_TSF_1.8  INPUT models (90ohms) at TypSlowFast conditions- 1.8V I/O

   

INPUT105_TT_1.8  INPUT models (105ohms) at TT conditions - 1.8V I/O 

   

INPUT105_FF_1.8  INPUT models (105ohms) at FF conditions - 1.8V I/O 

   

INPUT105_TSF_1.8 INPUT models (105ohms) at TypSlowFast conditions- 1.8V I/O

   

INPUT150_TT_1.8  INPUT models (150ohms) at TT conditions - 1.8V I/O 

   

INPUT150_FF_1.8  INPUT models (150ohms) at FF conditions - 1.8V I/O 

   

INPUT150_TSF_1.8 INPUT models (150ohms) at TypSlowFast conditions- 1.8V I/O

   

 

   

regards

   

Jayasree

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Anonymous
Not applicable

Hi Jayasree,

   

Yes that's a good example model (I've looked at several CIO models... all very similar.) 

   

The INPAD does have ODT, but is not assigned to Data.  Data use the DATAIO model (the one I pasted.)  Check the [Pin] list:

   

B2              DQ27              DATAIO  

   

Thanks again,
Joseph

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