SN65DP141: S-Parameter model

Mita-san

DP141 s-parameter model does not include random jitter, you have to add the random jitter externally as part of the simulation.

In a time-domain simulation, the position of each TX clock edge is varied according to the specified jitter types and characteristics. Random jitter (RJ) is assumed to have a Gaussian distribution, deterministic jitter (DJ) is assumed to have a flat PDF between the minimum and maximum values, and duty cycle distortion (DCD) is divided between successive clock edges. Sinusoidal jitter (SJ) is specified with a magnitude and frequency. The total jitter applied to an edge is the sum of the individual contributions. In a statistical simulation, the individual jitter PDFs are convolved with the unjittered RX eye to produce the final eye diagram.

Thanks
David

David-san,

Thank you for your answers.

Please allow me to dig into this topic.

First of all, let me confirm my understandings.

The simulation mode reflects the deterministic jitter which includes DCD,
Sinusoidal jitter (SJ) (or Periodical Jitter), data dependent jitter (or ISI) etc.

If it is true, the last piece is Random Jitter.
It has Gaussian distribution.

Q1. how much noise (RMS), do you need to add when you pursue simulation?

Q2. Is the noise magnitude independent to the EQ gain?

Q3. If it depends on the EQ gain, how you set the noise magnitude?

Q4. If you need to add other jitter beside random noise, please let me know
how to model other jitters?

Mita

Mita-san

Q1, This depends on the estimate total system jitter, DP141 has 25-50fsRMS, then you need to add source Rj, plus any PCB Rj.

Q2. With DP141 model, it does not depend on the EQ gain.

Q4. For statistical simulation, jitter modeling is implemented differently depending on the EDA tools. For time-domain simulations, Tx jitter is added to the stimulus waveform.

Thanks
David