DP83867IR: Simulation Inputs Required

Keshav Rajanna

Prodigy 20 points

Part Number: DP83867IR

Tool/software:

Hello,

We are simulating RGMII Interface for 1Gbps speed.

Could you please provide us the following data

For exciting the RX (RXC, RD0, RD1, RD2, RD3, RX_CTL) signals at RGMII PHY what is the voltage value i should consider at the Input of the PHY IBIS Model? (For 3V3 IO Model and 1V8 IO Model)
How frequently does the RX_CTL and TX_CTL signals will switch, will it be same as data? from the below timing image taken from the PHY data sheet it shows that CTL signals also switch as same as data.

Regards

Keshav

3 months ago

0 Gerome Cacho 3 months ago

TI__Mastermind 39835 points

Hello,

IBIS data will not simulate MAC setup/hold time. It is meant to emulate signal integrity, so rise/fall and overshoot and undershoot.

There should be no stimuli needed on the input pins for the RX to toggle. Similarly, the RX_CTRL line should toggle in similar fashion to the data once properly setup.

Sincerely,
Gerome

0 Keshav Rajanna 3 months ago in reply to Gerome Cacho

Prodigy 20 points

Hello Gerome,

Since RX pins are the output pins from the PHY, why no stimuli needed? will it be taken care in the IBIS model itself?

Can you confirm with what are the exact stimuli setup I need to consider for read and write operation for TX and RX on the PHY Chip.

Regards

Keshav

0 Gerome Cacho 3 months ago in reply to Keshav Rajanna

TI__Mastermind 39835 points

Hello,

I acknowledge your email and will be responding back on Monday after consulting my team.

Sincerely,

Gerome

0 Gerome Cacho 3 months ago in reply to Gerome Cacho

TI__Mastermind 39835 points

Hello,

Please refer to this app note on how to use IBIS models. DP83867 model should function the same way as DP83TG720.

Sincerely,

Gerome

0 Keshav Rajanna 3 months ago in reply to Gerome Cacho

Prodigy 20 points

Hi Gerome,

Thanks for the app note.

I have an observation regarding the TX_EN/TX_CTRL pin (Pin 37 of the VQFN package). Based on the datasheet this pin is an Input.

However, in the IBIS model, the model name assigned to Pin 37 is GPIO. Furthermore, in the model selector for GPIO only lists output models.

[Model Selector] GPIO
gpio_1p8 1.8V digital Output
gpio_2p5 2.5V digital Output
gpio_3p3 3.3V digital Output

Could you please advise on which model should be used for Pin 37 of the VQFN package (48 pin Package)

If the IBIS model available on the website is the old version. please provide the latest IBIS file.

Regards

Keshav

0 Gerome Cacho 3 months ago in reply to Keshav Rajanna

TI__Mastermind 39835 points

Hi Keshav,

Thanks for the feedback. As mentioned, it seems that this pin looks to be improperly spec'ed as a GPIO. Instead, please overwrite the designation to match the other TX pins and I will take an action to rectify this in the public file.

Sincerely,
Gerome

0 Keshav Rajanna 3 months ago in reply to Gerome Cacho

Prodigy 20 points

Hi Gerome,

For the TD lines there are different models assigned in the IBIS model, there is a different model assigned for TD0, TD1 and TD2, TD3 as shown below

25 TX_D3 GPI
26 TX_D2 GPI
27 TX_D1 GPIO_SGMII_IN
28 TX_D0 GPIO_SGMII_IN

What is the significance of using different models for the TD lines?

Regards

Keshav

0 Gerome Cacho 3 months ago in reply to Keshav Rajanna

TI__Mastermind 39835 points

Hello,

These designations are intentional and appropriate as they capture the inner workings of the device. Please continue with your simulations.

Sincerely,

Gerome

0 Keshav Rajanna 2 months ago in reply to Gerome Cacho

Prodigy 20 points

Hi,

Can you provide the VIH and VIL ring back requirements for the PHY chip for 3P3 IO and 1P8 IO.

Regards

Keshav

0 Gerome Cacho 2 months ago in reply to Keshav Rajanna

TI__Mastermind 39835 points

Hi Keshav,

The VIH and VIL for 3.3V and 1.8V VDDIO are located in our datasheet. For 3.3V, VIH and VIL are 1.7V and 0.7V, respectively. For 1.8V, these are 1.26V and 0.36V, respectively.

Sincerely,

Gerome

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DP83867IR: Simulation Inputs Required