Bulk resistance compensation (was: New version...)

[Rick Jansen]

In message <2FDCBF11 at MSMGATE.M30X.NBG.SCN.DE> Haible_Juergen writes:

> The bulk resistor compensation circuit is new to me, too. Good idea!

The bulk resistance compensation is taken from S. Franco's book
too, with the difference that a diode is used in the original circuit
to get the same voltage drop as the Ube across one of the diff.
pair transistors. I used the 5-transistor LM3046, so I can use 
one of the transistors to really get a similar voltage drop.

I just received Electronote #72(?) with a VCO circuit, where they
say the trimmer in series with the integrator cap acts as a 
compensation for the discharge time at higher frequencies, but also
that you can compensate for the bulk resistance indirectly, simply by 
*over*compensating! This sounds logical, as the effect of this 
compensation is to speed up the charge/discharge cycle at higher 
frequencies, which acts against the effects of bulk resistance too...

Rick Jansen
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rick at sara.nl   http://www.sara.nl/Rick.Jansen
_____________________________________________
S&H's a module and s&h's looking good