OPA615 Hum suppression

Hello Toshi-san,

The OPA615 was designed primarily for video. I will have to do some research for audio circuits.

By HUM do you mean the 50/60Hz powerline noise?

You may want to also post this question in the audio forum. I'm sure someone there is familiar with this topic. It is possible that one of their suggestions would also apply to this amplifier.

I will leave this thread active, though, because this is one of our high speed amplifiers.

Regards,
Loren

Hello Toshi-san,
I am checking with some other engineers to see if they know more about this subject. Is the hum from a 50Hz/60Hz power line? Does this require some kind of notch filter to eliminate the hum?

-Samir

Loren-san, Samir-san, thank you very much for your help. Yes, the noise come from a 50Hz/60Hz power line. My customer want to reduce the HUM noise because LMH1981 does not work properly with hum noise in the input video signal. Does the OPA615 work as notch filter ? or do you have any other solution to elominate the hum noise ?

Hello Toshi-san,
I haven't had much success finding out from some of the other folks on the team why the OPA615 datasheet suggests that it will be a good fit for hum suppression. I tried designing a 60Hz notch filter but the component values are very large and I don't think they are reasonable to design in an actual circuit. I am currently out of office but will try reaching out to some folks over email if they have any thoughts/inputs. Sorry I cannot be of more help right now.

-Samir