LMX2592: Channel isolation

Hi Naveen,

To my knowledge we don't have data on this for LMX2592. You also caught us at a terrible time - our team is in the middle of a site move and we don't have a lab until after 15th Dec (about two weeks). We might have this board at a different site; I'll check and post a new response if we can take a measurement.

Based on LMX2594 which has a similar output structure, I would expect isolation will be around 50dB typical for outputs with dissimilar frequencies with our recommended external pull-up components - I don't think we have any data or even a simulation to suggest maximum isolation, since it depends heavily on the filtering between the external pullup supplies. For comparison, the LMX2820 has internal pull-ups on separate supplies, and sees around 40dB typical isolation with dissimilar frequencies when we do not include any filtering between the two supply pins.

Regards,

Derek Payne

Hi Derek,

Thanks for the reply and inputs.

Kindly post a response once you get measurement details.

Regards,

Naveen

Naveen,

We just got back into the lab. I had time to configure a test setup for isolation, but since you asked for a maximum value I'm taking some time to iterate through several frequency conditions to see if there's any frequency-dependent trends. I should have an answer for you tomorrow.

Regards,

Derek Payne

Hi Derek,

Can you please update on the issue?

Regards,

Naveen.A

Hi Derek,

Did you get any data on the isolation?

Regards,

Naveen.A