[sdiy] 2164 temperature compensation

[Benjamin Tremblay]

Replying to this so I can monitor responses, because I am curious. I noticed that the 2164 could operate at low supply voltage. But i interpreted the specs to mean you need at least a trickle of negative voltage to get the correct range out of this device. Maybe in this circuit where it’s not being used as a vca it’s okay?

Benjamin Tremblay

> On Aug 2, 2026, at 9:35 AM, Rutger Vlek via Synth-diy <synth-diy at synth-diy.org> wrote:
> 
> 
> Dear list,
> 
> I'm working on a sawtooth oscillator for a new personal synth project and have a question about temperature compensation with the 2164, as proposed in the datasheet (Figure 11): 
> https://www.soundsemiconductor.com/downloads/ssi2164datasheet.pdf
> 
> I noticed that the proposed compensation scheme takes a bipolar CV input (-5 to +5V) and generates a temperature compensated control signal for the final exponentiator (VCA2) that is also bipolar in nature, centered around the unity-gain point (0V) of the 2164. I wondered: was this chosen for practical reasons, or does the temperature compensation (or expo conversion) work more accurately around the center-point of the 2164?
> 
> The reason I ask is because I'd like to adapt this scheme to work with a unipolar CV coming from a MCU. I'm also wondering if I can drop VCA3, as high frequency compensation of non-temperature dependent effects can be entirely done inside the MCU.
> 
> Best,
> 
> Rutger
> 
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20260802/8c112f4c/attachment.htm>