[gpsd-dev] GR-701W hangs on Pi-3
hmurray at megapathdsl.net
Fri Jun 3 07:02:08 UTC 2016
esr at thyrsus.com said:
>> I donât think the issue is that the board designers cut cost -
>>thereâs power regulation on the boards.
> I'm sure there is. But not a lot of it. Many are the reports of problems
> in the presence of wobbly power - I'd heard a few myself even before I
> started working with these boards.
The regulators on the Pi provide 3.3V. The Pi expects the 5V to be close to
I think the basic problem is that the USB specs allow a lot lower than 5V and
the Pi designers didn't leave room for that.
USB spec says:
All hubs and peripheral devices shall be able to provide configuration
information with as little
as 4.00 V at the device end of their B-series receptacle. Both low and
high-power devices need
to be operational with this minimum voltage.
Figure 11-5 shows the minimum allowable voltages. Note that under transient
supply at the device can drop to 3.67 V for a brief moment.
The 24 AWG is a step in the right direction but not good enough if you expect
These are my opinions. I hate spam.
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