LMH7324: How to change RSPECL to LVDS, when use LMH7324 in Standard Setup

Rock,

Please see section 3.4 (p.13) on interfacing ECL logic to LVDS: 

Alternatively, the customer can set up the LMH7324 directly as an LVDS driver by setting VCCO at 2.5V. Did Fan Wang recommend for you to configure the LMH7324 as RSPECL and then convert it to an LVDS signal?

Regards,
Jonny

Hi Jonny,

Thanks for your reply!

Fan wang didn't recommend, just customer want to try it. Because the customer doesn't want to use negative power.

We have seen this document, but we didn't confirm whether RSPECL to LVDS configuration is the same as PECL to LVDS configuration.

So RSPECL to LVDS configuration is the same as PECL to LVDS configuration?

Thanks a lot!

Best Regards,

Rock Su

Rock, 

It wont be the exact same since RSPECL has a 400mV swing compared to 800mV.

You will have to rework some of the equations described in section 2 of the document I mentioned above, but they are all there for you.

If you have trouble calculating the resistors to convert the RSPECL output to LVDS, please let me know and we can take this offline.

Regards,

Jonny