[sdiy] Elektron Digitakt teardown

[MTG]

Is this a common approach?  What do Moog and the many others do to avoid 
ground loops when USB is part of the setup along with audio and 
110v/220v line power?

Also you have the consideration of the 5v coming in on the USB with or 
without the mains power being connected or on.  I've never done a 
self-powered USB device (only bu powered), but this must be a common 
concern.

On 7/9/2017 1:44 AM, Julian Schmidt wrote:
>   * The "Analog"-series devices had a USB isolation to avoid having a
>     ground loop when the device is connected to a computer and an audio
>     interface. The USB isolation chip was removed. Instead, there is now
>     an isolation between the analog side and the digital side of the
>     circuits. The power rails and grounds for the analog and digital
>     sides are entirely isolated. That way, ground loops are still
>     prevented, but in addition digital noise is kept away from the
>     analog circuity much better.
>   * The magnetic NVRAM that was used in the "Analog"-series devices was
>     removed (probably too expensive and too small - the largest
>     available on the market is currently 16Mbit). Instead, they use a
>     1Gbit DDR2 SDRAM powered from a Supercap. So, effectively you get
>     the "persistent" memory (no loss of data when power-cycling, even
>     without saving your project) but it porbably won't last 20 years
>     like the magnetic NVRAM