player80
Full Member level 2
Hi,
I have interfaced an old intercom - basically everything works fine but what bothers me is the direct connection of the system with the microcontroller board.
I'm first filtering the DC offset with a capacitor and amplify the signal with an op-amp.
Now I'm still tying the ground of the intercom together with the ground of my system, I'd like to keep them completely separate since I cannot take the power from the intercom to power the microcontroller (as soon as I touch it it will introduce some noise on the audio out line).
What would be a better solution for that?
Using an audio transformer?
Or is there a better (integrated) way nowadays?
I have interfaced an old intercom - basically everything works fine but what bothers me is the direct connection of the system with the microcontroller board.
I'm first filtering the DC offset with a capacitor and amplify the signal with an op-amp.
Now I'm still tying the ground of the intercom together with the ground of my system, I'd like to keep them completely separate since I cannot take the power from the intercom to power the microcontroller (as soon as I touch it it will introduce some noise on the audio out line).
What would be a better solution for that?
Using an audio transformer?
Or is there a better (integrated) way nowadays?