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Subject: Re: [korgpolyex] Re: About the NJM2069 Chip

From: Michael Hawkins <korgpolyex800@...>
Date: 2014-06-04

No one has the spec for the chip. So there's no datasheet to go to unfortunately. I pestered Korg for months. They tried very hard to find the details of it. Oki were also quite friendly but they too could not help.

I would check the DW8000 schematic carefully and see what the supply pins are connected to very, very carefully.

Pin 22 is Vcc - in the Poly, it's connected to +5V
Pin 11 is Ground (0V) - in the Poly, it's connected to ground - 0 volts.
Pin 12 is Vee - in the Poly, it's connected to -5V

It makes sense that the thing is CMOS, in which case, it can run in dual supply mode (as Poly above) or in single supply mode (DW8000 perhaps?) where Vcc is +12 and Vee is tied to ground.

But you will need to check this.

Mike



On Tuesday, June 3, 2014 9:22 PM, "ackolonges ackolonges@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.