[sdiy] Moog ladder & State-variable example lectures up

[Aaron Lanterman]

On Wed, 29 Mar 2006, ASSI wrote:

> On Mittwoch, 29. März 2006 08:24, Aaron Lanterman wrote:
>> I = [something with Ic I forget off the top of my head] *
>>      (sinh(v/vt) / [1 + cosh(v/vt)]
>>
>> So it's almost tanh, but it has this extra "1" in the denominator...
>> I'll write up my derivation when I get time.
>
> The latter term reduces via:
>
> u = v/vt
>
> 1    2 sinh(u)
> - ------------
> 2 2 + 2cosh(u)
>
> to
>
> 1             1      / v \
> - tanh(u/2) = - tanh| --- |
> 2             2      \2vt/
>
> (the very same derivation I've gone through in my OTA paper and now know
> by heart).

Oh!

Interesting, so that diode bridge gives a tanh I/V response like an OTA 
(except the current flows all the way through both directions...)

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