TUSB7320 PCIe ref clock logic

Sachin Kurawatti

Prodigy 130 points

Other Parts Discussed in Thread: TUSB7320, TUSB7340

What I/O standard is prefered for TUSB7320 100MHz PCIe ref clock input?

Is it fine, if provided with 100MHz LVDS clock?

Regards,

Sachin

over 13 years ago

0 Elias Villegas M. over 13 years ago

TI__Guru* 76130 points

Hello Sachin,

Yes, the PCI Express REFCLK+/- signal is a LVDS.

It is described in detail on the PCI Express Card Electromechanical Specification Rev 1.1

Regards.

0 SACHIN KURAWATTI81378 over 13 years ago in reply to Elias Villegas M.

Prodigy 100 points

Hello Elias Villegas,

Can I also use 100MHz HCSL clock for TUSB7320 REFCLK+/-?

Regards,

Sachin

0 Elias Villegas M. over 13 years ago in reply to SACHIN KURAWATTI81378

TI__Guru* 76130 points

Hello Sachin,

The main difference between the LVDS and HCSL are that HCSL support higher frequencies and more power than LVDS; so if you meet the electrical specs for the TUSB7340 it won't matter what signal type you use.

I don't recommend HCSL due to its high voltage swing which is very close to the maximum input voltage of the TUSB7340.

Regards.

Interface

Interface forum

TUSB7320 PCIe ref clock logic