Subject: Re: [linux-audio-dev] open-source like hardware
From: Nick Bailey (n.j.bailey_AT_elec.gla.ac.uk)
Date: Mon Jan 14 2002 - 10:38:08 EET
Pieter wrote:
> Max,
>
> For the moment, I'm also a student in electrical engineering. I've chosen
> for micro-electronics, and I too have a VLSI project coming up in a few
> weeks.
> I don't think VLSI is an option. First of all, designing a chip is, in my
> opinion, more difficult than designing a PCB. And, as far as I know,
> it's very costly. The programs used to design these things aren't on the
> freeware/open-source market (yet?). That might be solved if you can use
> the software your department has.
http://www.gnu.org/software/electric/electric.html
>
> But then there is the chip production... my colleges learned me that VLSI
> chips are cheap when produced in large volumes, but as you need several
> chip masks (@ about 10,000$ a piece), are not that cheap for low volume...
> Don't hesitate to correct me if I'm wrong.
I think your biggest problem (whether you go for external box, internal or
whatever) will be the D/A and A/D quality. I made one with a Transputer link
adaptor years ago, using 16-bit Burr Brown converters. Never got more that
about 14 bits right, whatever we did to the supply, screening, etc. This is a
black art. The rest is just hard work 8-) Mind you, this was over a decade
ago now, and things have moved on.
You are right about the cost of custom silicon. You might still consider CPLD
(Complex Programmable Logic Devices) though. Or a DSP. You might be able to
get the chips fab'd through your University, who will have an educational
discount scheme of some sort, but then nobody else will be able to get them,
and you will have to get them right first time anyway (which hardly ever
happens).
Sorry if this is getting too off-topic 8-)
Nick/
This archive was generated by hypermail 2b28 : Mon Jan 14 2002 - 10:35:22 EET