Feature #5063

Allow un-powered operation

Added by laforge about 1 month ago. Updated 28 days ago.

Target version:
Start date:
Due date:
% Done:



Right now, the OpenVizsla always needs to be powered. As soon as power is removed, the communication between host and device breaks down. We received reports that a simple diode can be added at one location in the design to prevenr this problem from happening.

Let's analyze this in detail and decide if the diode change can be applied to "master", or if we have to look for something more sophisticated, avoiding the voltage drop over a diode.

Related issues

Related to OpenVizsla USB tracer/analyzer - Feature #5076: Update board revisionIn Progress


#1 Updated by mschramm about 1 month ago

  • Status changed from New to In Progress
  • % Done changed from 0 to 10

Unfortunately no real news here yet. - We got an image showing a hand-soldered patch wire from nework "+5V" behind L2 connecting to "targetVBUS" - but no diode visible so far, maybe it's in series to L2 on the (non-imaged) PCBA top side. So this all looks like the unit is powered from the host all the time...? We'll inquire again.

#2 Updated by mschramm 30 days ago

  • Status changed from In Progress to Stalled

No news here by now.

#3 Updated by laforge 30 days ago

mschramm wrote:

No news here by now.

well, then maybe ask again the user who requested it :)

#4 Updated by mschramm 28 days ago

  • % Done changed from 10 to 20

We're going to merge the other solved design improvements and not wait for further details regarding this user requirement. - They came up with another 'problem' (not further specified) which they also solved with a diode, - but no schematics on either detail yet, maybe next week.

#5 Updated by mschramm 16 days ago

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