see if you can find data on cat5 insulation breakdown voltage
its prob ok tho
keep the current around 1mA at most
Posted by renesis at 11:48 | permalink | 0 comments
lordpil's blog
yeah not seeing anything about minimum current
says recommended range is 0 to 500mA
itll prob be okay and you can always put an led or whatever
if it takes 160mA all the time it wont be a problem
Posted by renesis at 11:42 | permalink | 0 comments
so it has like ~.47V dropout
if you trust the digikey specs (don't, check the datasheet)
says .035V @ 100mA
at higher current, the Ron of the FET inside the vreg and anything else affecting output impedance become more of an issue
just make sure the cap on your switcher is big enough that you dont get more than like .5V ripple and itll be okay to put that after the 5V switcher
you might have to draw extra current
if that IC doesnt draw enough current when itd idle to keep the regulator working
sec
Posted by renesis at 11:35 | permalink | 0 comments
LDO usually use a FET pass transistor and have drive circuitry that doesnt need headroom
like, 78XX regulators need like 3-4V headroom
so you have to select unregulated supply capaitors so your ripple voltage doesnt drop below this
like, you have a 20V rail, unregulated
and a 7815
say it has 3V dropout, you need to select capacitors so that your ripple at max current doesnt exceed 2V
if the 20V rail drops below 18V because the caps got sucked out too quick, itll show up as ripple on the 15V regulated rail
so yeah, LDO is maybe .1V to 1V dropout voltage, usually
Voltage - Output 3.3V
Voltage - Input 3.77 ~ 10 V
Posted by renesis at 11:30 | permalink | 0 comments
if you mean after, the 3.3V reg needs to be an LDO or itll drop out
so use a 3.3V ldo linear vreg off the 5V, use a 3.3V standard vreg off 24V (possible dissipation issues), or use a 3.3V switcher off the 24V
can prob use a 3.3v switcher off the 5v too
low drop out
normal vregs use BJT pass transistors and need a few volts headroom
to deal with Vbe drop and drive/reference circuitry
Posted by renesis at 11:25 | permalink | 0 comments
when im in a meeting its usually its something bad =D
im almost late
Posted by renesis at 01:11 | permalink | 0 comments
tokae is tokae why you talking about it in here
haha @ other channel
Posted by renesis at 00:27 | permalink | 0 comments
fenders? =\
i want to get rid of my bike
big steel 24" bmx thing
haha @ rear fender
just funny looking, looks functional tho
neat
ha
i need one of those
ive only had one since i started working here
i think i want my dreds back
Posted by renesis at 00:22 | permalink | 0 comments
haha
that sounds bad for knees
wtf are you guys talking about
besides that
motorcycle or bicycle or what
Posted by renesis at 00:17 | permalink | 0 comments
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