ADG1613 - how to handle the GND pin in mixed signal designs?

I'm about to use the ADG1613 in a single supply audio / mixed signal design. Vss is connected to the analog ground (0V), Vdd to the analog power rail (12V in this case). There also is a virtual GND for the opamps of the circuit (6V). The digital part consists of a microcontroller with a seperated 3.3V supply.

Now I'm wondering about the GND pin of the ADG switch. Should it be handled as a return path for the logic control inputs like a "digital ground" pin on an ADC? The datasheet entry is: "Ground (0V) Reference", which sounds more like a reference point where analog and digital ground is connected.

So I'm a little confused, may be someone can help me with this question?

Thanks a lot,

Mathias

Parents
  • GND and Vss of the ADG1613 are not internally connected.

    The GND pin is the reference for the level shifters inside the part to actuate the switches.

    Your analog and digital ground will likely be connected somewhere in the system. It might or might not be a good idea to make the connection at the ADG1613.

    Like May, I would suggest you connect both the GND and VSS pins to the analog ground plane.

    Your worry about return currents are probably unfounded as the inputs draw almost none. You can reduce the effect of capacitive coupling by inserting series resistors into the control lines to filter them.

    Klaus

Reply
  • GND and Vss of the ADG1613 are not internally connected.

    The GND pin is the reference for the level shifters inside the part to actuate the switches.

    Your analog and digital ground will likely be connected somewhere in the system. It might or might not be a good idea to make the connection at the ADG1613.

    Like May, I would suggest you connect both the GND and VSS pins to the analog ground plane.

    Your worry about return currents are probably unfounded as the inputs draw almost none. You can reduce the effect of capacitive coupling by inserting series resistors into the control lines to filter them.

    Klaus

Children
No Data