Cut power from USB but keep data connection. Galvanic isolator?

[Barry_Sound]

Hi guys, I have a DAC without power switch that runs on an external PSU and the 5V from the USB port. That means the DAC is always on when connected to my Mac, even when the PSU is switched off.

Question: Can I use a galvanic isolator to cut the power but keep the data connection? Any other ways?

Thanks

 

[Barry_Sound]

Here is a cheap thing I found on Amazon, might give it a try.

https://www.amazon.de/PortaPow-USB-Power-Blocker/dp/B094FYL9QT/

 

[dualazmak]

For one of my small USB DAC unit (which needs 5V from USB cable), I use this simple biwire-type USB cable;
https://ay-denshi.com/item-biwire-usb/
The USB Type-B should be connected to the DAC unit,
The red-marked USB-Type-A (5V lines only) should be connected to outer/external stable transformer-type clean DC 5V power supply ,
The non-marked USB-Type-A (clean signal lines only) should be connected to PC (or Mac)

You would please note, however, some of the similar small DAC unit (even if it also has outer/external 5V supply capability) still do need 5V just as "signal" through the USB cable for its triggered power-on.

 

[Barry_Sound]

For one of my small USB DAC unit (which needs 5V from USB cable), I use this simple biwire-type USB cable;
https://ay-denshi.com/item-biwire-usb/
The USB Type-B should be connected to the DAC unit,
The red-marked USB-Type-A (5V lines only) should be connected to outer/external stable transformer-type clean DC 5V power supply ,
The non-marked USB-Type-A (clean signal lines only) should be connected to PC (or Mac)

You would please note, however, some of the similar small DAC unit (even if it also has outer/external 5V supply capability) still do need 5V just as "signal" through the USB cable for its triggered power-on.

All right, this cable splits power and signal into two separate channels. Not sure what I would do with a power only 5V USB-A plug in my case. All my PSUs run on mains power.