[sdiy] SSM2164 VCAs

[Tom Wiltshire]

David,

This confused the hell out of me at first too. The examples in the  
datasheet are very lax about what level the CV should be (Fig 24  
shows 0-5V CV used). However, the figures are quite clear:
  -33mV/dB.
Hence you need 3.3V for fully off -100dB, and -0.66V for 20dB gain. A  
10V envelope is overdoing it quite a bit. This isn't too big an issue  
since you've probably got a CV summer in the circuit anyway, but you  
need to watch the levels and offsets.

Regards,
Tom


On 9 Jun 2009, at 01:50, David G. Dixon wrote:

> Also, the gain can
> increase as much as +20dB or decrease as much as -100dB.  At one  
> point, the
> datasheet mentions that a 0 to 10V CV range will give gains from 0  
> to -100
> dB.  Hence, I'm presuming that a 0 to -2V CV range will give gains  
> from 0 to
> +20dB, although this is never stated.