Ok, now define "circuit".
Ok.
Why? What's the difference between building an analog circuit using opamps, comparitors, and DACs, vs gates? The same sorts of skills apply.
Somebody does.
-- Keith
Not if the "design" is a purely logical construct, coded most likely in Verilog or something. There's no "circuit" and no electrical issues involved, just boolean logic. Which is why you can get a degree in Computer Science or even Computer Engineering and know nothing about electromagnetics. I don't agree that the same skills apply; digital design is almost always qualitative (unless you get into cordics or other interesting algorighms) and circuit design is usually quantitative. Even DSP is electricity-free.
John
I just went thru an "interview" for a project... management liked me a lot, but I seemed to make the PhD "VHDL architect" nervous, probably because I saw straight thru his bull-shit and he knew it from the questions I asked.
I'm betting that I don't get the project.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
I recently had to make an emergency high-speed drive into Silicon Valley to show two PhD's, one an expert Verilog programmer, that they had disconnected a ground that mattered.
The way the world is going, you've got to be diplomatic with these software types if you want the biz. Electricity scares them.
John
I have traveled halfway around the world to fix dumb-ass PhD blunders ;-)
Yep. His eyes glazed over when I said "device-level design" ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
No, it's just that the math and tools are a little different. Again, I don't see the difference between wiring analog blocks together and wiring digital blocks together. Same swamp, different alligators.
Sure, but you're not likely to be *building* a very complex widget armed with nothing but the fact that 1+1=10. Ma nature has her ugly side, even in "digital" electronics.
You've never considered transmission lines, delay rules, loading, speed/power products,...? ...and PHBs. ;-)
-- Keith
Yes. If you do that, and actually *design* in that environment, you might be a circuit designer. If all you do is type Verilog, you're not.
John
I think I'll start carrying a Taser ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
I was going to comment that Tasers seem to be mostly used on the mentally defective, but considering the thread, its probably the right tool for the job ;)
Cheers Terry
Its fundamentally different. This is it
To all intents and purpose, a software or digital specification, is always physically realisable.
For analogue, a given specification may be out with the laws of physics. Analogue electronics is fundamentally restricted by:
F(sigma, speed, power) that is is it is impossible to arbitrarily achieve power, speed and accuracy specification. e.g
There are numerous specifications that all have to be achieved in the real analogue world, not the virtual world of digital and software. That is, the design of a digital multiplier is a routine exercise, the design of an accurate high speed, low power analogue multiplier with low feed through, is very difficult, or impossible.
And no, don't defend with yeah, software and digital has constraints, because these same ones are also in analogue, so don't differentiate.
Analogue is constrained by the real world. Its all about trading off one conflicting specification from another.
Kevin Aylward B.Sc. snipped-for-privacy@anasoft.co.uk
"There are none more ignorant and useless,than they that seek answers on their knees, with their eyes closed"
like infinite resolution?
digital also suffers from such constraints, but Moores law keeps coming to the rescue.
IMHO the real problem with digital/software, as others have mentioned, is that its so easy to fiddle with, so encourages appallingly bad design followed by massive amounts of twiddling. Analogue is nowhere near as forgiving...
Telling a programmer they can update embedded code easily is often a great way to ensure their output is s**te.
Cheers Terry
But your still missing the point with this argument, thats why I said, dont use that argument!
Sure, there are some "tecnicalities" in the final implementation of digital or software, but for analogue the "technicalites" *is* the problem.
I don't see this argument as relevent.
The issue is that a given analogue problem, may not be solvable in principle. Software and digital problems are (essentially) always solvable in principle.
Kevin Aylward B.Sc. snipped-for-privacy@anasoft.co.uk
"There are none more ignorant and useless,than they that seek answers on their knees, with their eyes closed"
Not true. I've seen many timing specifications that cannot be met. C, Cdv/dt, and all that.
Same swamp, different alligators. I think Intel would love to have a 1W 10GHz P4, too.
Only if you don't have to implement it with real silicon.
Realizable technology limits both realms in similar ways.
And I can have a zero-delay, zero-power, zero-size gate? Get real.
I'll take a coupla hundred million, all wired correctly, thanks.
-- Keith
Neither is "digital" hardware design.
Sure, but embedded programming hardware design. There may be six months and tens of $millions between turns.
-- Keith
But tell a digital design group that an IC spin will cost eight months and 50 million dollars, and they will usually be very careful.
And programmers have funny ideas about "updating code easily." Oh, just send the user a CD that they install, and tell them to make a flash programming cable, and follow this simple procedure...
John
Yes, but even simulation is fast running out of steam. Instructions per second is growing far faster than available sim cycles. The hardware can run more cycles in a few seconds than can be simulated in months.
;-)
-- Keith
You missed the point: that's where "limitless" digital transitions into the parent, "finite" analog ;-)
Tim
-- Deep Fryer: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms
conclusion: pointless debate.
digital *is* analogue, as Tim points out. the real issue is that clueless fools who cut and paste remain so; regardless of it being VHDL or transistors. Its just that VHDL and the like are easier for the clueless to get into....and can make their errors harder to see.
Cheers Terry
Yes, indeedy! The fact is that both sides of the fence have similar goals; draining the swamp (while sometimes stroking a PHB). ...and I've been on both sides. TANSTAAFL.
What I do *not* understand is the avoidance of simulators. If the job is so simple that they're not needed... Yes, and I mean both logic and circuit simulators. Face it, the big bucks go to the people designing the most complicated widgets.
-- Keith
Your missing the point.
Ahmmm. Again, you are simply missing the point. Its trivially obvious that digital hardware may be limited in basic speed and power, but this limitation is not relevant to the point being made about analogue.
The number of varibles to be satisfied in an anlogue design is way more than digital. Like, why do you think digital is used in the first place, like audio, saving data? Why don't we just do it by analogue methods? That is, why represent anlaogue information as 0,1 in the first place?
Look, digital design is a solved problem. Given that one requires a register, barrel shifter, accumulator, software can just go and synthesise the damm thing. This just can't be done with analogue, and never will. Analogue design requires conciousness. This is reflected in the salaries companies are prepared to pay analogue engineers,
Kevin Aylward B.Sc. snipped-for-privacy@anasoft.co.uk
"There are none more ignorant and useless,than they that seek answers on their knees, with their eyes closed"
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