DP83867IS: RJ45 integrated magnetic

Kazuki Itoh

Genius 10185 points

Part Number: DP83867IS

Hi team,

Could you please review if DP83867IS can work with 7499111121A from Wurth?

My customer is concerned that the risk of the common center tap of the 7499111121A.

Can some different DC bias voltages cause unwanted power dissipation by using this RJ45 connector?

Regards,

Itoh

over 5 years ago

0 Cecilia Reyes over 5 years ago

TI__Genius 9920 points

Hello Itoh,

Do you have the specs of the Wurth magnetics? Please refer to the DP83867IS datasheet to ensure the part meets the datasheet specs of the magnetics.

Thanks,

Cecilia

0 Kazuki Itoh over 5 years ago in reply to Cecilia Reyes

TI__Genius 10185 points

Hi Cecilia,

Thank you for your reply.

Here is the datasheet.

https://www.we-online.de/katalog/datasheet/7499111121A.pdf

Can the common center tap pulse transformer cause unwanted power consumption by the bias voltage difference?

Regards,

Itoh

0 Cecilia Reyes over 5 years ago in reply to Kazuki Itoh

TI__Genius 9920 points

Hi Itoh,

Thank you for sharing the datasheet. The common center tap is a concern because each center tap on the side connected to the PHY must be isolated from one another and connected to ground via a decoupling capacitor (0.1 µF recommended).

Let me know if you have further questions.

Thanks,

Cecilia

0 user5364394 over 5 years ago in reply to Cecilia Reyes

Prodigy 30 points

Hi Cecilia,

Could that concern lead to increased heating or device failure?

Regards,

Oyamada

0 Kazuki Itoh over 5 years ago in reply to Cecilia Reyes

TI__Genius 10185 points

Hi Cecilia-san,

Mr. Oyamada is my customer and he is in the loop. Could you please answer his question?

Regards,

Itoh

0 Cecilia Reyes over 5 years ago in reply to Kazuki Itoh

TI__Genius 9920 points

Hello Itoh and Mr.Oyamada,

Tying the center taps together could mean that the device may not work properly.

We recommend isolating the center taps.

You can review section 2.3 of our DP83867 troubleshoot and design guide: http://www.ti.com/lit/an/snla246a/snla246a.pdf

Thank you,

Cecilia

0 Kazuki Itoh over 5 years ago in reply to Cecilia Reyes

TI__Genius 10185 points

Hello Cecilia,

Thank you so much for your help!

Regards,

Itoh

Interface

Interface forum

DP83867IS: RJ45 integrated magnetic