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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Ok guys, I need a little help.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Sounds weird, but I need to drive a bunch of leds with a
pitch CV.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>For example I’d like the LEDS to see 0-1 amp (50 leds)
corresponding to a 0-2volt input. The LEDS are all in
parallel, and do not have resistors on each one.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I poked around and found a really simple circuit that is
nothing but an opamp and a single resistor that does this V-C conversion.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Works great, but the amp could never drive a whole stack of
leds. So, I guess I need a circuit that I can use a power transistor with
at the output and some sort of pot to adjust the sensitivity (based on the CV
range).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If anybody knows of info already on the web regarding this, just
point me in the right direction<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>On another topic, I’m currently experimenting with
various paints for silkscreening front panels, and I should have some
information on which paint is best if anybody is interested. I got my
screens from Westar, and they look great.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks in advance for any assistance!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>phil<o:p></o:p></span></font></p>
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