10.06.2016 Views

eldo_user

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

IBIS Models Support in Eldo<br />

Example 2—Pseudo-Differential Tx-Rx System<br />

Netlist Explanation<br />

_IO_DIFFOUT OUTp OUTn D_drive<br />

+ file="diffsource.ibs"<br />

+ component="diffsource"<br />

+ pin="1" inv_pin="2"<br />

The above lines instantiate an IBIS differential output buffer diffout with non-inverting output<br />

connected to outp, inverting output connected to outn and digital input connected to d_drive.<br />

The output buffer is located in the diffsource.ibs IBIS file within the diffsource component. The<br />

differential buffer is recognized from the pin and inv_pin keywords. Pin names given using<br />

these keywords must match those in the diffsource.ibs IBIS file under the [Diff_pin] keyword.<br />

TLp outp 0 inp 0 Z0=50 TD=0.3ns<br />

TLn outn 0 inn 0 Z0=50 TD=0.3ns<br />

Instantiates a pair of ideal transmission lines, one of them connected between the nodes outp<br />

and inp with ground reference, and the second one connected between the nodes outn and inn<br />

with ground reference. Both transmission lines have 50Ω characteristics impedance and 0.2ns<br />

time delay.<br />

_IO_DIFFIN INp INn D_receive<br />

+ file="diffload.ibs"<br />

+ component="diffload"<br />

+ pin="1" inv_pin="2"<br />

Instantiates an IBIS differential input buffer diffin with non-inverting input connected to inp,<br />

inverting input connected to inn and digital output connected to d_receive. The input buffer is<br />

located in the diffload.ibs IBIS file within the diffload component. The differential buffer is<br />

recognized from the pin and inv_pin keywords. Pin names given using these keywords must<br />

match those in the diffload.ibs IBIS file under the [Diff_pin] keyword.<br />

Rterm D_receive 0 1e6<br />

Connects a 1MΩ resistor between the digital output d_receive of the input buffer and ground.<br />

This has no impact on the results avoids having a node with less than two connections.<br />

.param VHI=1.0<br />

.param VLO =0.0<br />

.param TDELAYL=0<br />

.param TRISE=300p<br />

.param TFALL=Trise<br />

.param TSAMPLE=3000p<br />

vin d_drive 0 pattern VHI VLO TDELAYL TRISE TFALL TSAMPLE 1011010001 R<br />

Instantiates the stimulus vin for the system. The source is connected between the nodes d_drive<br />

and ground. It is defined using the pattern function with high voltage level of 1V, low voltage<br />

level of 0V, 0 starting delay time, 300ps rise and fall times, 3ns sample time, and having the<br />

pattern 1011010001.<br />

Eldo® User's Manual, 15.3 793

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!