On Mon, Aug 24, 2015 at 6:28 PM, Dominique Dumont domi.dumont@free.fr wrote:
On Monday 24 August 2015 14:19:49 Luke Kenneth Casson Leighton wrote:
anyone see any flaws?
It should work.
But I don't see why the first transistor is needed.
it stops the back-voltage down the 2nd resistor (top right-side, connected to 3.3V) into the CPU (VREFTTL). imagine that VREFTTL is 1.8v, and the transistor wasn't there: the *entire CPU* would be powered from that resistor at well above the CPU's rated voltage.
with a 28nm CPU, it would be irreversibly damaged by the over-voltage coming back down that resistor.
can't have that!
Well, it's only a few cents...
:)
All the best
-- https://github.com/dod38fr/ -o- http://search.cpan.org/~ddumont/ http://ddumont.wordpress.com/ -o- irc: dod at irc.debian.org
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