[sdiy] Temperature Compensated Exponential Converter Using SSM2164

[Magnus Danielson]

Aaron Lanterman wrote:
> 
> On Aug 29, 2009, at 4:28 PM, Tim Parkhurst wrote:
> 
>> 2009/8/29 HOSHUYAMA <houshu at muj.biglobe.ne.jp>:
>>> Hello List,
>>>
>>> I developed a new style temperature compensation method for
>>> exponential converter using SSM2164.
>>>
>>> http://houshu.at.webry.info/200908/article_1.html
>>> http://houshu.at.webry.info/200908/article_2.html
> 
>> Very impressive Sam, but does this work significantly better than
>> using a tempco resistor with the 2164? This is how the Mankato VCF is
>> set up, but I have to admit I've never really measured the temp
>> compensation (especially since it's a VCF and not really sold as a
>> VCO).
> 
> I think the nice thing about this approach is that tempcos aren't always 
> easy to come by.

Not as easy as they used to. Also, they where an approximation at best 
anyway.

What I like is that it uses a part which is fairly usefull for many 
things and available. The other half could be used for a second 
oscillator or for waveshaping or something other usefull. How about 
current-switching for a triangle wave core?

Cheers,
Magnus