CYP15G0403DXB HOTLink II Transceiver

[masu_1341616]

Hello,

I want to connect to optical transceiver & receiver.  it usually output after through capacitance for AC coupling.

But I can see DC spec of receiving differential signal which is Min Vcc-2.0(V ILE) on your data sheet.

Could it receive this signal after through AC coupling  signal?

[Roy_Liu]

Yes, CYP15G0403DXB HOTLink II Transceiver is capable of driving AC-coupled optical modules or transmission lines.

The apps note below page 11/12 has some example.

http://www.cypress.com/documentation/application-notes/an060-frequently-asked-questions-about-cypv15...

[masu_1341616]

Thank you your quick response. I have a additional question about this.

I can understand it about CML & LVPECL.  How about PECL?   Is it correct with the same understanding?

[Roy_Liu]

Yes Suzuki-san. Applicable for PECL.

[masu_1341616]

Hell additional basic question.

Please check my understanding.  I can see to connect AC coupling output signal to receiver input directly

Because it have pull-up register to pull up the common mode voltage in CYP15G0403DXB like below.

Is it correct?

Please advice me.

[Roy_Liu]

Do you mean "I can set to connect AC coupling output" instead of "I can see to connect AC coupling output"?

Where do you get the circuit diagram?

[masu_1341616]

yliu​-san,

Yes, "I can set to connect AC coupling output to receiver input directly looks like your app note.

Usually when differential signal through out from AC coupling,  common-mode voltage is 0V.

If receiver doesn't have a any voltage bias circuit(EX. pull-up) ,  it doesn't meet common mode input SPEC.

That circuit diagram is general serdes receiver logic diagram.  Not Cypress.

Best regards,

Masa

[Roy_Liu · Accepted solution]

Hi Masa-san,

Then I think your understaning is correct.

However, please note the termination resistor at INX side of CYP15G0403DXB is required.

Thanks

Roy

[masu_1341616]

Hello Yliu-san,

Thank you for your answer!

Best regards,

Masa