Monday, April 7, 2014

(another) 48h day

staying awake in extended periods shifts your mind to weird states . . .

. . . ? redesigning the capacitor covers ?XD ::


for test-build we don't want to have exposed conductors around << /!\ /!\ /!\ >> otherwise what we just did was generating a heat insulation that in Hi-AC signal env. may cause the un-wanted sudden temp. rise and explosion -- i blew decades ago shortened X-mas lights' active preload - well it stayed in operation 60h and was operating below the max. ~ 250 V allowed marked on caps - i guess they newer tested'em for this particular mode ...
... in other words - as with modern Ni-MH chargers - designing "always-ON" equipment is reasonable to support with /!\ thermal /!\ shutdown relays(/controller)
_______________


about 48 h - prj. :: a long story short it's test-approved forgot and now re test-approved fact that designing a simple boost converter for LE 1.5 V feed performs a lot of WORSE than the SPICE predicts ((there're few exceptions of course ...)) - so, well in common / most cases -

random ::
+

 - the identified issue is BJT-s' base bias -- usually 200 k is "near unity" 4 CE-stg. with 1.2 V feed -- junction charging C-E saturation just occurs too slow - in common 30mA from single battery is most efficient upper limit ::

1.2 V x 30 mA / 12 V = 3 mA >> correcting (best known 74%) >> 2.2mA ??? while the Spice shows boldly 300 mA input and 22 mA output -- while again best practise goes more like 600 mA in and 10 mA e.g. >> 1 7 %   e f f i c i e n c y <<

SUM :: we go C what the fet-s can do -- starting with basics ::


((now i have to build that bullsh¡t -- whitch doesnot mean it's gonna work ...))


[EOP]

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