what is the additive jitter of the mux CBTL02042ABQ and the recommended power supply filtering for the Vdd pin ?

[lawrencehui]

We are using the NXP CBTL02042ABQ USB3 mux on our current design and are in need some additional information that is absent from its datasheet. Could you please provide support for the following questions ?

MFG: NXP

MFG P/N: CBTL02042ABQ

1. What is the additive jitter of the mux ?

2. What is the recommended power supply filtering for the Vdd pin ?

[TomasVaverka]

Hi Lawrence,

Sorry for such a long delay in answering these questions, I had already requested assistance from our device group, but have not heard back so far. I just pinged them again today and will get back to you as soon as I have more info.

Best regards,

Tomas

[TomasVaverka]

Hi Lawrence,

Here is the answer from our apps team:

1. The additional jitter that CBTL02042ABQ may bring in strongly depends on the signal speed.

2. A 0.1uF plus a 0.01uF for VDD should be OK.

Best regards,

Tomas

[lawrencehui]

Hi Tomas,

What will be the additive jitter of the mux if the mux is at 5Gbps for USB3?

Thanks

Lawrence

[TomasVaverka]

Hi Lawrence,

For 5Gbps USB3.0, which fundamental frequency is 2.5GHz, CBTL02042 7GHz -3dB bandwidth should be sufficient, the jitter added by the MUX will be just a couple of picosecond. Please note a MUX is bandwidth limited, and there are other high frequency components in the channel, fast signal rise/falling edge, for example, may affect the jitter.

Attached please find the CBTL02042 S-parameter model. I would recommend that customer adds it into their channel model to run a full channel simulation.

Best regards,

Tomas

[lawrencehui]

Hi Tomas ,

Very good info. Thanks.

The customer is primarily interested in random jitter component of additive jitter of the mux. The USB3 spec requires Rj 3.27ps rms max. If the NXP mux is adding “a couple of picoseconds” mostly as random jitter then that would be consuming a large portion of the 3.27 ps rms budget. Can NXP please provide the measured/characterized Rj additive jitter of the mux ?   

Thanks again

Lawrence

[TomasVaverka]

Hi Lawrence,

Sorry for my late response, additional Rj is about 0.1ps rms.

Best regards,

Tomas

[lawrencehui]

Hi Tomas,

Thanks for the answer.

If the typical Additive Random Jitter (Rj) is about 0.1ps rms. What would be the Max Additive Random Jitter (Rj) ?

Additive Random Jitter (Rj) - Typical: 0.1 ps rms

Additive Random Jitter (Rj) - Max: ??

Also, is there an evaluation or validation board NXP can short-term lone to the customer to do experiment with in the lab ?

Thanks

Lawrence

[TomasVaverka]

Hi Lawrence,

Unfortunately we do not have the max Rj value.

Regarding the evaluation board, there is one available, but currently only to our sales team. Can you please get in touch with our local sales engineer and provide more information about the customer/application? Or share with us this information by creating a standard ticket?

Best regards,

Tomas