[sdiy] AD633

[JH.]

The good thing about this chip is that you don't need to
trim the quadratic terms.

With most cheaper solutions, nulling the offset will minimise the bleedthru
of the carrier and modulator, but won't minimise the quadratic term (i.e.
2nd harmonic) of these signals bleeding thru.

The EMS VCS3 has trimmers to minimise the quadratic bleedthru, and I
think I've published a similar circuit based on the MC1496.
(Can't find th elink right now, but it should be out there.)

The AD633 doesn't need this. I've once tried to do this, and found the
633's own quadratic bleedthru supression can't be improoved with external
trimmers, i. e. it's very good already.
Need to trim the offsets, though.
(I'm doing this without trimmers now, using select-on-test resistors, as in
http://jhaible.heim.at/matrix_fx/jh_matrix_fx_osc1_core_board_sch.pdf )

JH.


----- Original Message ----- 
From: "Loscha" <loscha at gmail.com>
To: "JH." <jhaible at debitel.net>
Cc: "diy" <synth-diy at dropmix.xs4all.nl>
Sent: Sunday, June 18, 2006 11:52 AM
Subject: Re: [sdiy] SSM2164/SSM2210/SSM2220 possible group buy (was: LM394
from Futurlec)


I was eyeing off the AD633 the other dya.
It's a sweet chip.

On 6/18/06, JH. <jhaible at debitel.net> wrote:
>
> I would be in for some AD633. (DIP package)
>
> JH.
>
>
>
>
> ----- Original Message -----
> From: "Andre Majorel" <amajorel at teaser.fr>
> To: "synth diy" <synth-diy at dropmix.xs4all.nl>
> Sent: Sunday, June 18, 2006 10:16 AM
> Subject: [sdiy] SSM2164/SSM2210/SSM2220 possible group buy (was: LM394
> from
> Futurlec)
>
>
> On 2006-06-17 21:54 -0400, mark verbos wrote:
>
> > So I finally received my LM394's from Futurlec today. And it
> > only took 2 months! :)
> >
> > Anyway, I had no immediate use for them anyway, so I'm just glad
> > to have gotten them finally.
>
> Speaking of which,
>
> at some point, I'll have to get a bunch of SSM2210 and SSM2220
> from AD (much cheaper than through RS or Farnell). And some
> SSM2164 and high-end ADxxx op-amps too. If you want to do a group
> buy, let's talk. There's no hurry on my end.
>
> --
> André Majorel <amajorel at teaser.fr>
> http://www.teaser.fr/~amajorel/
>
>


-- 
Loscha of Edmaro
[The Reverse Engineers]
"I'm not a musician -- I'm a Scientist"
which part of sine (theta + index * sine (theta * ratio)) do you need me to
explain to you?