LTspice, a great program, but that UI! - Page 3

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Re: LTspice, a great program, but that UI!


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Not at all

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That is not the point. What part of "check out" and "exists" did you miss?

The only reason any competent engineer, that is designing for major  
production runs,  is not going to the most basic of "does anther part even  
exist", is if he has no idea that an alternative might exist. i.e. he was a  
clueless engineer. Dah..Gee,. looks like I have to go with this..dah...

What I can say, is that if I were hiring engineers, hiring an engineer that  
is bribed by a freebe bit of kit from a vendor, such that he wont even  
attempt to find a more optimum part, would not be at the top of my resume  
list.

-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html


Re: LTspice, a great program, but that UI!
On 14/03/2017 20:31, Kevin Aylward wrote:
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Kevin, you might be surprised at the number of analogue engineers who  
design by stitching together application notes.  I would say it's the  
great majority.  I never really appreciated the fact until I went  
freelance and was exposed to dozens of design teams, but the reality is  
that only a low percentage of the engineers doing board and system level  
design are competent in their craft.

What I usually see is that if an engineer manages to cobble together  
something in LtSpice (usually from the supplied examples) that meets the  
technical specs of whatever it is they've been tasked to do, then the  
design stage is over.



Re: LTspice, a great program, but that UI!
wrote:

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I have boards with 1100 parts. 10-layer boards with several FPGAs and
22 power supplies. Boards full of Eclips Plus logic and SiGe
comparators and power PHEMTS and RF transistors. Boards that sell for
$11,000. If I can knock out a switcher design in an hour, using an LTC
part, I can move on to the hard/fun stuff.

If I expect to build thousands of something relatively cheap (which I
prefer to not do!) I might spend some time evaluating cheaper parts,
which might not have a decent Spice model at all.

On that 22-supply board, I used mostly TPS54302 synchronous switchers,
very cool little parts. I breadboarded five different voltage outputs
with different inductors and caps and loop compensations. I have never
got WebBench to load on my PC.


--  

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement  

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Re: LTspice, a great program, but that UI!
On Tue, 14 Mar 2017 16:22:43 -0700, John Larkin

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Exactly.  For low volume, high margin, production it doesn't make
sense to spend a lot of time on support circuits.  High-volume, low
margin (they go together) designs, one spends a *lot* longer than a
half an hour optimizing things.
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Re: LTspice, a great program, but that UI!
wrote:

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Boy, ain't that the truth!  I don't know how many projects I've lost,
saying, "You're not listening, so I'm outta here."

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My personal burn is they come to me with a board heavily populated by
OpAmps everywhere, and want me to simply put it all on a chip.  When I
ask for an overall system spec, they get all grousey.  It's hard for
me to convince these dorks that an OpAmp function, on-chip, can often
be replaced with a couple of transistors... if any are needed at all.

Some of those very dorks lurk here >:-}
        
                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LTspice, a great program, but that UI!
On Tuesday, March 14, 2017 at 7:03:06 PM UTC-4, JM wrote:
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Grin, raises hand.  App notes or circuits ripped out of AoE.  
(Probably more of the later... do they even make good app notes any more?)  

George H.  
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Re: LTspice, a great program, but that UI!


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Excuse me a moment, whist I wipe the blood form my brow and the brick wall.

-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html


Re: LTspice, a great program, but that UI!
On Tue, 14 Mar 2017 20:31:14 -0000, "Kevin Aylward"

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You're being ridiculous.

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Wait a minute.  You said competent engineers optimized the designs
even for low volume production.  

You can't even search TI for an SMPS in a half an hour.  It takes
their FAE longer than that to find the best fit for some applications
(ones he hasn't already searched).
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For a prduction run of a hundred units?  Please!

Re: LTspice, a great program, but that UI!
On Tue, 14 Mar 2017 20:35:19 -0400, snipped-for-privacy@notreal.com wrote:

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Spend a couple of days to save $50!



--  

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement  

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Re: LTspice, a great program, but that UI!
On Tue, 14 Mar 2017 18:00:02 -0700, John Larkin

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Seems that's Kevin's business plan.  He could get rich that way.

Re: LTspice, a great program, but that UI!
"John Larkin"  wrote in message  
he hasn't already searched).
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Dah....

So, LT gets $50 bucks.

Point proven.

-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html


Re: LTspice, a great program, but that UI!

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Ho humm...

Look, we are trying to estimate the worth of LTSpice to sales, of all sales.  
Sure, low production runs, of low part count might well have an incompetent  
engineer unable to design in parts other than what is in his simulator,and  
hence spend $1,000 on LT Parts for the whole run.

BUT low production runs, don't generate much money for LT. Because, they are  
dah... low production runs. Its the larger runs that will dominate profits.  
The larger the production run, and the larger the number of parts, the more  
money to LT, and the more incentive to avoid giving that money to LT.  
Dah....

You need to sum up the contributions from all sources.  So, sure, LTSpice  
has some value, but those requiring larger number of parts, that generate  
the most money for LT, will have a larger probability of need to check out  
the optimum part from other sources.

As for "optimize", its a no brainer for me to check out in a tiny fraction  
of the time needed to layout a board, design the system, do the design  
reviews etc...etc.., whether or not another part would be a better fit. Its  
truly trivial. I did that for 15 years, before the internet existed. We used  
data books then.

So, yes, even for low production runs *I* would indeed "optimise" by looking  
for alternatives, which would take maybe, an hour or so.

If it is really true, that 99% of engineers designing products today, are so  
incompetent to not check out alternates, than I retract all my claims.

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Your trying to claim that, its an amazing, staggering amount of work to do  
minimal checkout of alternatives. I don't.

Getting a design together, even for  run of 100, is going to take way, way  
more time than checking out another parts

What size is the design? 100 chips, 1000 chips. How long does it taker to  
design a system with 1000 chips. If its a two op amp, 100 off guitar effects  
pedal, how much money will that get LT?


-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html


Re: LTspice, a great program, but that UI!
On Wed, 15 Mar 2017 20:26:10 -0000, "Kevin Aylward"

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That's what I've been saying.  Low-volume is LT's bread and butter.
They have a few interesting/unique parts that we use but they're way
too expensive for hgh-volume production.  At 100/month I used several
of their parts but at 10K/month, I haven't been able to justify one.
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That group doesn' t buy LT.  That's the point!

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So you have no idea of the number of (e.g.) power supplies available
now.  IOW, you're talking through your ass.
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Utter bullshit.

Engineering includes economics.  

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You're obviously clueless.  
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Re: LTspice, a great program, but that UI!
On Wed, 15 Mar 2017 20:34:09 -0400, snipped-for-privacy@notreal.com wrote:

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LTC is selling about $1.5 billion a year. ADI is paying $14.8 billion
to acquire them. Somebody is buying their stuff.

I was told that ADI will be moving their part models to LT Spice. That
would be smart.


--  

John Larkin         Highland Technology, Inc

lunatic fringe electronics  


Re: LTspice, a great program, but that UI!
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It would also be a good idea to snag AD's current unencrypted models.  

Cheers

Phil Hobbs

Re: LTspice, a great program, but that UI!
On Thu, 16 Mar 2017 05:41:04 -0700 (PDT), snipped-for-privacy@gmail.com wrote:

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Yep.
        
                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LTspice, a great program, but that UI!


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Well, we we will leave it at that then.

-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html



Re: LTspice, a great program, but that UI!
On Monday, March 13, 2017 at 3:26:57 PM UTC-4, John Larkin wrote:
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I'm small time, the price difference for LT parts hardly matters.
    
(Given the cost of box, switches, knobs, connectors, time etc.)
It's nice that someone caters to the smaller customer, I hope some  
of that stays with the AD buy.  

George H.    
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Re: LTspice, a great program, but that UI!
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For us it is guesswork, a statistician with the capability to perfom
experiments and see detailed figures would be able to put a number on it.  
said number would then be a trade secret.

--  
This email has not been checked by half-arsed antivirus software  

Re: LTspice, a great program, but that UI!

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For LTSpice to be of value to LT, it only has to generate a tad more than  
Mike's salary, lets guess that at $500k p.a :-)


-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html


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