DIY ICs

gilid

Member
2002-01-25 9:28 pm
France
Not to sound too negative, but I am a firm believer in the principle that our (DIY) efforts are best applied to where they will have the most gain. Until we have table top silicon foundries, I do not see DIY integrated circuits being realistically feasible. Unless someone in the group who works for a fab can moonlight for us... ;)

Pehaps we can try casting our own enclosures & heatsinks in the meantime!:)
 

MRehorst

Member
2002-05-17 8:48 pm
You can make your own analog ICs. You go to any of the many semiconductor foundries and hand them $50k-500k for a mask set (depending on the process) and all the CAD files and they will run a wafer of your ICs through their fab. Of course, this may be contingent on how many such wafers you intend to run through their fab per month...

Then you go to a packaging house and hand them a pile of money and they'll saw the wafer and package the parts for you. Of course, this may be contingent on how many such wafers you intend to run through their factory per month...

The IC manufacturing process is so expensive that the only way it makes economic sense is to make a lots of ICs (hundreds of thousands to millions). The process is not flexible enough to allow easy/inexpensive modification.

I have recently seen ads for analog"gate array" type chips that are one time programmable (I think). Instead of logic gates, they have analog function blocks that can be connected together. That is probably as close as you'll ever get to DIY analog ICs, until someone comes up with a new process you can run via your ink-jet printer...

MR
 
MRehorst said:
[snip]
I have recently seen ads for analog"gate array" type chips that are one time programmable (I think). Instead of logic gates, they have analog function blocks that can be connected together. [snip]

MR

Mark, yes, you'll find them at www.anadigm.com. They are analog gate arrays, a bunch of opamps, switches, rectifiers what have you, which you can program to make certain functions. Not really hifi but very usefull for auxiliary functions like psu regulators or power amp protection circuits or filters. Program can be changed even on the fly, so a controller may "built" a new circuit depending on what's going on in the system. Fascinating. And they have an evaluation board.

Cheers, Jan Didden
 
I think a home made vacuum tube instead would be cool, and closer to reality too. Jam jar, light globe filament, flyscreen wire, metal tubing, decent vacuum pump. It's gonna be gassy by commercial standards, but the resulting pale blue glow would look good in any darkened loungeroom.

And with a hand wound output transformer and hand made chassis, that would have to be the ultimate in diy. Maybe even powered by a hand-cranked generator for diy electricity too. ;)

GP.
 
Welcome to the future!!

"How far do you guys think the day is when we DIYers will make our own ICs and possibly tweak ones that have already been made."

we are, sort of, half-way there...those PIC-circuits make it very easy to construct gadgets that would be near impossible for a homebrewer otherwise...if you have got the nerves to compile those damn files...they're not very good for a man's mental health...
 

mirlo

Member
Paid Member
2002-07-12 9:55 am
San Diego
MOSIS ...

Actually you can get ICs made in small quantites for a lot less:

http://www.mosis.org/

... but still ends up being rather expensive.

Although the process described as "low noise analog" CMOS 1.5 micron is dirt cheap (relatively speaking) at $1100 or so for 5 parts, I suspect it wouldn't really be suitable for anything like what people here think they want.

More likely would have to use one of the BiCMOS processes.

You can buy an awful lot of AD8610s for $1100.