DP83826E:Differences between DP83826E and DP83822I Ethernet Connections

Hi Chaesok,

Q1:

I briefly looked over your schematic and it looks good, for a full schematic review please fill out the schematic checklist and return to me. It can be found under the Design Tools & Simulation Tab in the DP83826 Product Page.

https://www.ti.com/product/DP83826E#design-tools-simulation 

Q2:

The only difference will be the driver used. Both the DP83826 & DP83822 Linux Drivers can be found here: 

https://www.ti.com/tool/ETHERNET-SW

Regards,

Alvaro

Hello Alvaro, thanks for the response..

The checklist was sent in a private message.
One more question is that the potential of the TX, RX signal is currently unstable. So I connected 3.3V Pullup to the signal. After that, the potential comes out stable, is this the right way?

Thank you.

Hi Chaeseok,

I saw your private message. Schematic reviews take at most 5 business days. I will reply again before end of day Friday Feb 2nd at the absolute latest.

Thank you for your patience.

Regards,

Alvaro

Hi Chaeseok,

I have sent you the reviewed schematic in a private message.

chaeseok lim said:

One more question is that the potential of the TX, RX signal is currently unstable. So I connected 3.3V Pullup to the signal. After that, the potential comes out stable, is this the right way?

Regarding this question, are we referring to the TX/RX signals that are connected to the MAC interface?

Regards,

Alvaro

Hello Alvaro,

I'm sorry. Can I change my question?

[This is the signal that is checked by TD_P Pin when connecting to the Ethernet port.]

I have revised the circuit according to the current checklist advice, and the signal is coming out as above.(Pull-up has been deleted.)

However, there is no Ethernet connection.

Is it because the potential is lower than 3.3V?

If it's correct, may I know why it comes out low?

Thank you.

Hi Chaeseok,

So now the PHY is unable to link up with the link partner? Can you send me the values of Reg 0x0-0x1F?

The waveform you sent me looks good, the amplitude of the signal will NOT be the VDDIO voltage. Please see the table pasted below.

Regards,

Alvaro

Hello Alvaro,

There is a difficulty in reading the current register value.
Can I get a register value for 83826E?

I have a few more questions.

What is the difference between PHY1 With SMI Address 0x01 and PHY1 With SMI Address 0x07.
Is the difference between MDIO PHY Address 0x01 and MDIO PHY Address 0x07 a register value.
Is there a correlation between PHY1 With SMI Address and MDIO PHY Address.

Thank you always for your response.

Hello Alvaro,

"This resolved my issue" was pressed incorrectly.

That's right. I'm having trouble reading the register value now. So I want to get the correct register value (DP83826E) for the above circuit.

Also, the results from the troubleshooting guide test

It came out as above.

Is there no communication problem with the signal in the circle of the waveform above?

Hi Chaesok,

The probe shot of the Link Pulse you sent looks good! I wouldn't be concerned with that. 

Back to the register read issue, when I reviewed your schematic I mentioned the MDIO pin requires a 2.2 kΩ PU resistor. Has this been added to your board?

MDC does NOT requires a PU of any kind. 

Regards,

Alvaro