using such a powerful tool as LTspice is has been extremely invaluable.

invaluable?

I think either you or your translation software make an excellent point.

ak

 

They're just another tool. BTW how much is "too much"? Can we have a precise definition -- puhleeze!?

 

Has simulation made us dumber?

Have calculators made us dumber?

Collectively, I think a strong argument can be made that both have -- as have many other things. Increasingly people can't navigate around their own city, let alone take a cross-country trip, without a GPS. Give them a street map or, heaven forbid, just give them a street address, and they are completely lost (literally and figuratively).

Technology provides tools that, used effectively, makes us "smarter", but humans are inherently lazy (most of technology comes about by our willingness to work really hard in the quest to make our lives really easy) and so a significant portion of people do not use those tools to enhance their skills, but rather to make up for the lack of them. So they use simulators and calculators and lots of other tools to do their thinking for them and, having done so right from the beginning, they aren't even able to ask whether the results make sense, let alone actually answer that question.

In the realm of small circuits that can be breadboarded or even done on a PCB you can debate whether simulators should be used and, if so, at what point and how heavily. For IC design there really is no debate -- you virtually always CAN'T prototype the physical circuit because the behavior of circuits on an IC is a very different critter than the behavior of discrete circuits. So you would have to spend tens of thousands of dollars (at the low end) to fab the chip, wait a month or three to get it back, test it, and then decide what changes you wanted to make and repeat the process. Not a viable option -- you need to strive very diligently for first-silicon success and good simulations are the only thing that give you even a remote hint of a chance.

 

They're just another tool. BTW how much is "too much"? Can we have a precise definition -- puhleeze!?

No, you can't. The best you can hope for is useful qualitative definitions. You are using a tool too much when you become reliant on it to do things that you should be able to do yourself. When you HAVE to use a calculator to multiply 7 by 9, you are using it too much. Now, the next question will be whether or not you can have a precise definition of what you should be able to do yourself and, again, the answer is no. In that sense it's the same as looking for a precise definition of what is and isn't "art" (which is probably simple in comparison).

 

It's a tool. Sometimes I use it a lot, sometimes I won't open it for months. I like it (LTspice) for switching power supply designs especially if I am using a Linear Technology chip.

 

invaluable?

I think either you or your translation software make an excellent point.

ak

This is one of those oddities of English (and I imagine many other languages have similar examples, but English is likely the worst). The prefix in- is usually considered to mean "not", so you have fertile and infertile, for example. But in specific cases it either has no effect on meaning or it is used to indicate "to a high degree", so you have flammable and inflammable, which mean exactly the same thing, and you have valuable and invaluable in which invaluable means so valuable that the value can't even be stated.

 

If you can convert your requirement into a formula you can build it.
A simulator is, in some cases, handy it will save time and could you even slap in the face. ( on the display picbuster stupid donkey)
But they could fail or be wrong so this puts you back in square one.
Its like a scope what do I measure the signal or the influence of the probe tip at point of measure.
Anyway I do not use simulators anymore.

 

Going back even more, you can ask the question, Did phone books make us dumber?

Einstein claimed he didn't know his own phone number and there was no reason to know it because he could look it up (since he already had is name memorized).

Phone books, calculators, simulators, ... One person can claim they make us dumber. I would describe it as "ignorant people can use a simulator", educated people can be much more efficient with the use of calculators and simulators.

Translating to other occupations, do Excel spreadsheets make accountants dumber? I think accountants are good (A/B students) or bad (B/C students) at their jobs long before they learn how to use excel.

 

If you can convert your requirement into a formula you can build it.

Way too simplistic.

Requirement: I want to measure the universal gravitational constant to ten sig figs.
Formula: G = (F·r^2) / (M1·M2)

If you can build it, you would become famous.

 

The lives of many pilots/astronauts have undoubtedly been saved by the use of flight simulators.
For electronics, one advantage of simulators is a reduction in the inventory of components needed for circuit design.
I regard Spice as a tool for use at the pre-breadboard stage, to get ball-park figures for component values and for catching errors (some at least ). One does, however, need to be aware of its limitations.

 

I don't simulate, except between my ears. Then I build.

God, I envy you...

 

invaluable?

I think either you or your translation software make an excellent point.

ak

Ouch!... no, I don't use a translation software. Never had it, never will.

I made the classic mistake of "literal translation". The word invaluable, (which is written exactly the same in spanish, btw) means "priceless" in my mother tongue.

 

No, you can't. The best you can hope for is useful qualitative definitions. You are using a tool too much when you become reliant on it to do things that you should be able to do yourself. When you HAVE to use a calculator to multiply 7 by 9, you are using it too much. Now, the next question will be whether or not you can have a precise definition of what you should be able to do yourself and, again, the answer is no. In that sense it's the same as looking for a precise definition of what is and isn't "art" (which is probably simple in comparison).

I don't need advice on when to use them and when not to use them and I was prodding the TS/OP for his opinion. I know what your opinion is already as well as many of the other frequent posters. For those trying to decide on how or when to use them I think it is prudent to become familiar with them. I would not want to dissuade anyone from learning about them. Similarly I would not want to dissuade anyone from building a few and testing a few before building a lot.

 

Ah, I misinterpreted your question. I didn't see a specific post that made a statement about "too much" and so I thought you were throwing out a general question. My apologies.

 

invaluable?

I think either you or your translation software make an excellent point.

ak

Mmhhhh.... it seems that I did not make a mistake after all:

http://www.merriam-webster.com/dictionary/invaluable


So I'm taking it you were twisting my words to make an ironical point?

 

First, lets understand the place a simulator takes in the rank of circuit design. The top rank is the brain coupled with a pencil, paper and the creation of a schematic. Manual math, a slide rule, a four function calculator, a scientific calculator, and a simulator are just analysis tools; so the simulator can't design a circuit any more than your slide rule could. The simulator is just the top analysis tool; a good thought to remember. Also, if the solution to your problem does not lie within the locus of the schematic the simulator will yield false results for years; only the brain has the ability to reveal a false path.

I conjure up a block diagram, reduce the blocks to circuits, analyze the circuits with approximations and a calculator, build the circuit, test the circuit, modify the circuit, and then use a simulator to take performance data. I do this one block at a time, so that I am always sure that my circuit performs as expected. Trying to do this as a system is virtually impossible! You may get something that works but you miss so much because you depend on the simulator to think for you.

 

For large systems you can take the reverse approach -- start with a behavioral description that meets the requirements of the overall system and then break it into blocks. Use behavioral descriptions for each block that still satisfy the overall requirements. You know have a behavioral and interface requirement for each block. Continue this process until a block has gotten small enough that it is reasonable to design an implementation that satisfies it's behavioral and interface requirements. Once you have done this for all blocks, you (should) have a complete implementation that satisfies the overall system requirements. The hardest part in this approach is coming up with adequate behavioral requirements for the overall system -- but then that is just another way of saying that the hardest part of solving many problems is gaining a firm understanding of what the problem is.

 

Mmhhhh.... it seems that I did not make a mistake after all:

http://www.merriam-webster.com/dictionary/invaluable


So I'm taking it you were twisting my words to make an ironical point?

Or maybe pointing out that 'invaluable' can't be modified by the adverb 'extremely'?

 

I remember reading a science fiction short story set in the future where the character was brought up on heresy charges because he claimed he could do math in his head but everyone knew that only machines could do math.

 

I remember reading a science fiction short story set in the future where the character was brought up on heresy charges because he claimed he could do math in his head but everyone knew that only machines could do math.

There's another one where someone figured out how to do math when pen and paper and it was classified as a high military secret because of the potential advantage it would give if the computers were taken out.

There's also a plot-line in an old Buck Rogers in the 25th Century episode (late 1970's?) in which Buck wins at Blackjack by counting cards because the computer only uses a single deck since no one has the math ability to even contemplate odds or how counting cards could possible be helpful.