BJG145
Joined: 06/08/05
Posts: 2159
Loc: Norwich UK
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IC design - how do they do that?
#993996 - 21/06/12 06:06 PM
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I was just looking at the picture of the innards of the CLASP system reviewed in May's SOS
with its rows of chips, and it just baffled me. How the heck did someone create that?
Could anyone give me an insight into the development process of something like this, or
point me to a book or something? I imagine that something like this necessitates a team of
specialists, but I don't know what the specialisms are. I mean, are there people who
understand what a wide range of ICs do, without understanding how they operate, for
instance...? A bit like knowing how to use an application without knowing how to write the
code...?
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dmills
Joined: 25/08/06
Posts: 2130
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Re: IC design - how do they do that?
[Re: BJG145]
#994007 - 21/06/12 07:23 PM
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The person you describe is called an Electronics engineer, there may also be a software
guy (But not always, plenty of electronics types can program micro controllers), and maybe
a hardware cad person.
Something like CLASP decodes into really 24 near
identical sets of routing electronics, a control processor, the PC plugins and some
twiddly (but important) bits around the edges (Power supplies, control interfaces and
such), as such it does not really appear all that complex to me, far worse is something
like a big analogue synth where you have many different circuits instead of 24 sets of the
same with some extra bits around the sides.
The biggest pain would have been
either the PC software side or the sheer number of connectors in play, electronically the
thing is not that complex (Bit like a mixing desk, lots of repeats of the same thing).
Analogue electronics usually needs the designer to understand at least a little
about what goes on in the chips (Ebbers Moll and friends as a minimum), but silicon layout
is a whole other (and highly specialist) game.
Interestingly modern digital
design makes heavy use of hardware that can be configured by software, things called
FPGAs, very cool technology and you can get tens of thousands of logic elements on a chip
that you then configure into whatever circuit you want by writing a description in a
hardware design language. This has largely removed the need to design custom digital chips
at least for small to medium market products.
Regards, Dan.
-------------------- Audiophiles use phono leads because they are unbalanced people!
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hollowsun
Joined: 20/01/05
Posts: 4511
Loc: Cowbridge, South Wales
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Re: IC design - how do they do that?
[Re: BJG145]
#994015 - 21/06/12 08:13 PM
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Quote BJG145:
I mean, are there
people who understand what a wide range of ICs do, without understanding how they operate,
for instance...?
Yes. And there are
people who actually design these ICs, not just piddly little things with a few pins
on them but things with a millions of switches inside and billions of permutations.
I know a chap who can visualise such things in his head, mock it up using an FPGA
(as dmills mentioned above) and then have it all cast in silicon!! That will
then go into a product that he hasn't the first idea how to operate except at the most
rudimentary level for testing! Other engineers working on the stuff will be at the top of
the tree in their knowledge of audio, analogue and digital audio and electronics wit
years, even decades, working on design and manufacture but will often (even typically)
have no experience of actually using it.
I was at the aforementioned
chap's house once - he was designing the ASIC (Application Specific Integrated Circuits -
the really big bugger ICs at the heart of some gear) and the doorbell went so off he went
to answer it. Came back : "Sorry - washing machine repair man"
"What? You need
a washing machine repair man? Brain the size of a planet, building an ASIC with several
million switches in it and you can't fix your own washing machine?!"
"Fix it? I
don't even know how to use it!"
He's not the only electronics genius I've known
who has trouble with an electric kettle!
-------------------- Website / Music Lab Machines / Blog
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Hugh Robjohns
SOS Technical Editor
Joined: 25/07/03
Posts: 18390
Loc: Worcestershire
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Re: IC design - how do they do that?
[Re: BJG145]
#994031 - 21/06/12 11:30 PM
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Quote BJG145:
I was just looking
at the picture of the innards of the CLASP system reviewed in May's SOS with its rows of
chips, and it just baffled me. How the heck did someone create that? Could anyone give me
an insight into the development process of something like this
A lot of the 'chips' you see in that picture
are actually sealed relays that perform the audio routing for the different operating
modes.
However, from a design point of view it's really not all that
complicated in concept. For a start, the analogue audio side is, as Dan says, 24 lots of
some relatively simple signal routing performed via sealed relays between the I/O
connectors on the rear panel.
The sealed relays themselves are controlled by
some form of electronic switch which are commanded by the logic circuitry, part of which
can be seen in the form of the two big chips on the base circuit board.
The
logic circuitry and the relays need power, so there is a power supply in the box, with
transformer, AC to DC rectifiers, smoothing capacitors, voltage regulators and all
that.
Ther is also some logic and interfacing associate with the tape machine's
remote transport control, and some front panel stuff to accept control commands from the
panel buttons and to drive the panel displays.
Then there is the more complex,
but relatively common data interface gubbins to communicate with the host computer, so
that commands and tallys can be sent back and forth between the Clasp hardware and the
computer... and then the computer software that generates the control plug-ins and
interacts with the host DAW.
In effect, we are talking about a lot of separate
functional blocks, each with specific design requirements, and input and output signals
that must conform to specific design definitions and functions. To some extent, each can
be designed with some independence of the others provided each meets its design
requirements, and then the whole lot can be moulded together to form an integrated system
that does what it is supposed to do.
Electronics engineering involves knowing
how to design a power supply, logic circuits, audio and data buffering, microprocessor or
microcontroller systems, and so on. There are specialists in different fields, of course,
too. And then there are software engineers who can write plug-ins, DAWs, operating systems
and so on. And sometimes the electronic engineers can do some of those things too... and
vice versa.
Education is a wonderful thing! 
A good place to start to get a handle on electronics design is a book called The Art Of Electronics I
started with that book nearly 40 years ago! 
hugh
-------------------- Technical Editor, Sound On Sound
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grab
Joined: 08/07/07
Posts: 2626
Loc: Cambridge, UK
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Re: IC design - how do they do that?
[Re: Hugh Robjohns]
#994147 - 22/06/12 12:24 PM
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Quote Hugh Robjohns:
A good place
to start to get a handle on electronics design is a book called The Art Of
Electronics I started with that book nearly 40 years ago! 
And it's still pretty much the bible
today. 
Like any complex job, the answer is quite simply that you keep
breaking it down until you get to manageable tasks. You look at a cathedral and think
"how the hell did they build that?!" And the answer, like any building, is one brick at a
time. Just more bricks than usual, and a more complicated architecture job! But you do
have to start from an initial idea of "it's going to work like *this*", and that's the
real added-value part. It's why architects and civil engineers earn more than
bricklayers.
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James Perrett
Joined: 10/09/01
Posts: 9660
Loc: The wilds of Hampshire
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Re: IC design - how do they do that?
[Re: Hugh Robjohns]
#994204 - 22/06/12 02:11 PM
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Quote Hugh Robjohns:
A good
place to start to get a handle on electronics design is a book called The Art Of Electronics I
started with that book nearly 40 years ago! 
One of my first jobs as a young
electronics tech (around 30 years ago) was to incorporate one of Winfield Hill's cassette
logger designs into a measurement system that we had designed. It was a very ingenious use
of a stepper motor and very reliable.
I must admit that I don't have a copy of
the book - but I had a very knowledgeable college lecturer who made sure that we had good
notes which gave me a good start. I still have those notes around today.
James.
-------------------- JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.net
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