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but doesn't when powered by the 5V only USB.
Looking at the schematic of the original Pluto they connect the VUSB line of the 5v power input directly to the 5V rail of the device.
However, on the Pluto+ they have a couple of FETS and a diode connected to the 5V only USB. I assume to automatically select which
5V input to use if both the data and the 5v supply are connected.
Unfortunately, on my unit when I apply 5V to the 5V supply input only about 2,5v actually gets to the device. Consequently the light glows dimly
and the device never boots. I suspect either the diode or the FETs have blown or the circuit never worked in the first place.
There was a thread about this on the Pluto+ github page but no answer was ever forth coming from the designers.
Has anyone who has a Pluto+ seen this feature?
The Pluto+ uses 2 FETs and a diode to do the same thing. I am having some difficulty reading the Pluto+ schematic as Adobe doesn't
want to open the PDF file and when you view it on Github as a PNG file the text seems to be 2 pixels high.
Anyway the question still stands anyone with a Pluto+ been able to use the 5V input to power the unit?
on my cheap Chinese SFP+ 10Gb switch, and it works OK, I just had to hard code the IP address in the config.txt file to the IP address I am using for it on the switch (no DNS server). One day I should install iperf3 on the Pluto+ and see what that 1 Gb port can handle. I am getting around 9.5 Gb/s over a fibre to fibre link between 2 PCs.
In case anyone asks
British English = fibre
American English = fiber
I think the diode D5 may have failed as I get the following
USB Data 5v == works
USB PSU 5v == does not work
USB Data 5v + PSU 5v == does not work
Which seems to infer the p channel FETS are working
There is 5v on one side of the diode but nothing (very little) on the other