Ferrite Inductor Tolerance

[Fred Bartoli]

Joerg a écrit :

Well, Ian wrote that his app isn't power but precision audio. Different
thing.

I did use 1% inductors in "power" (was 50mW level) application a few
months ago.

Now, let Alwayswrong bitch...

 

[Archimedes' Lever]

Environmentally and financially not very friendly unless you can sell
the excess for a reasonable price.

There is nothing about coils that is bad for the environment, and I
never said anything about disposing of the remaining pieces.

The matching and culling also allows one to use an off target value, as
long as value matching is used, and the balance can be set by adjusting
the cap values if that is even needed.

Sorry, but most of the values will be fine, and you are wrong...
again... as usual.

 

[Archimedes' Lever]

How do you deduce that it's of little importance? Got a spy camera in
every enterprise, worldwide?




Environmentally and financially not very friendly unless you can sell
the excess for a reasonable price. Also, I found that when inductors
were at minus 15%-20% then, usually, the whole series was. In fact
sometimes over months. So no dice there, I would not sign the ECO for that.

It woiuldn't be an ECO, you dump chump. It would be the original
design spec.

 

[Archimedes' Lever]

Fractional Henry, yes. I never said I wanted 1%, I just wanted to know
what is the likely tolerance. Q or more than one is easy with inductors
even of several Henries.

Cheers

Ian

Look up ANY typical parameters and see that there is so much slop
aging, and drift in so many of them that your desired 'batch' of
inductors would be hard to gather up.

That is why a lot of such a custom value will be a 5x cost increase or
more over normal product runs.

 

[Archimedes' Lever]

I did use 1% inductors in "power" (was 50mW level) application a few
months ago.

50mW! Oh boy! That *REAL* power... not!

Were they >100mH, like the OP speaks of?

 

[Joerg]

There is nothing about coils that is bad for the environment, and I
never said anything about disposing of the remaining pieces.

The matching and culling also allows one to use an off target value, as
long as value matching is used, and the balance can be set by adjusting
the cap values if that is even needed.

Sorry, but most of the values will be fine, and you are wrong...
again... as usual.

It seems you have never dealt with the financials in production?
Component culling is heavily frowned upon by CFOs and accountants, for
obvious reasons.

 

[[email protected]]

There is nothing about coils that is bad for the environment, and I
never said anything about disposing of the remaining pieces.

Making things to be thrown away is not particularly environmentally friendly,
AlwaysWrong.

The matching and culling also allows one to use an off target value, as
long as value matching is used, and the balance can be set by adjusting
the cap values if that is even needed.

A lot of work for no gain. Excessive manufacturing cost is not exactly
environmentally friendly either. More resources...

Sorry, but most of the values will be fine, and you are wrong...
again... as usual.

Nope. AlwaysWrong, that's your job here. ...and in life, apparently.

 

[Joerg]

It woiuldn't be an ECO, you dump chump. It would be the original
design spec.

Oh, and how do you suppose you get an "original design" into production
without an ECO?

 

[Joerg]

Thanks for the input but I think you have misunderstood me. I already
have a source of suitable inductors. What I am interested in is the
factors that govern the tolerance of a production inductor (as it comes
off the line and before any selection process) and what the resultant
overall tolerance is likely to be for inductors around 1H. I am not
asking for help designing a product or in selecting parts.

Having designed several custom inductors and transformers, the largest
tolerance contribution came from the core material. Not the dimensions,
those are very precise, but from the materials properties.

 

[[email protected]]

Thanks for the input but I think you have misunderstood me. I already
have a source of suitable inductors. What I am interested in is the
factors that govern the tolerance of a production inductor (as it comes
off the line and before any selection process) and what the resultant
overall tolerance is likely to be for inductors around 1H. I am not
asking for help designing a product or in selecting parts.

I've found that manufacturers for highish L (1-5H), small, transformers seem
to have a hard time holding the permeability to -50%. After that, 5% DCR
tolerance seems to be about the norm.

 

[Archimedes' Lever]

It's hard to buy surface-mount NTC caps in reasonable quantities.

Form the leads of the beaded style into 'stands' for surface mounting.
Yes, it then becomes a hand installed part.

Same way we used to 'surface mount' axial leaded glass diodes before
the little barrel SMDs came out.

 

[Archimedes' Lever]

It seems you have never dealt with the financials in production?
Component culling is heavily frowned upon by CFOs and accountants, for
obvious reasons.

It seems that you have never dealt with the electronics industry for
the last 50 years.

Matching and culling was REQUIRED in many instances due to so many
variables that were around back then. You have no clue. You also have
no clue as to how such needs and tasks (and designs) were optimized to
minimize losses.

In other words, Shut The **** Up, idiot.

 

[Archimedes' Lever]

Making things to be thrown away is not particularly environmentally friendly,
AlwaysWrong.

Read it again, and show me where I said anything about disposal of
anything at any time.

You are a retard, and an ass.

 

[Archimedes' Lever]

Oh, and how do you suppose you get an "original design" into production
without an ECO?

You must also be an acronymical retard as well.

There is a difference between a design release and a change order of an
existing design.

Go away, you clueless bitch.

 

[Joerg]

You must also be an acronymical retard as well.

There is a difference between a design release and a change order of an
existing design.

So you guys release new designs without due ECO process? I sure hope you
don't design anything that can harm people.

 

[Archimedes' Lever]

So you guys release new designs without due ECO process? I sure hope you
don't design anything that can harm people.

We have anew design introduction department, and all the hammering out
gets done there, and yes, there ARE ECOs SUBSEQUENT to the original
design, idiot. The problem is that YOU apparently do not know the
difference between a new design and an ECO that makes a change to it.

Engineering Change Order. Can't change something unless it exists, so
it makes no sense to call a new design a "change".

You fucking idiot.

 

[[email protected]]

Read it again, and show me where I said anything about disposal of
anything at any time.

You obviously can't read what you're responding to. Illiteracy is like that.

You are a retard, and an ass.

Says the always wrong, scat fetishist, AlwaysWrong.

 

[[email protected]]

So you guys release new designs without due ECO process? I sure hope you
don't design anything that can harm people.

AlwaysWrong doesn't design anything, so no he doesn't release ECOs. Everyone
else here who does, uses an ECO process, certainly.

 

[Joerg]

AlwaysWrong doesn't design anything, so no he doesn't release ECOs. Everyone
else here who does, uses an ECO process, certainly.

Yup.

Maybe they have a different release process for new stuff even though it
typically _changes_ a product from previous to next generation. Having
two different release processes doesn't strike me as particularly smart,
but who knows

 

[Archimedes' Lever]

AlwaysWrong doesn't design anything, so no he doesn't release ECOs. Everyone
else here who does, uses an ECO process, certainly.

The ECO process is for changes made to a design, not the original
document.