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________________________________
From: Robert <birmingham_spider@...>
To: kicad-users@...
Sent: Tuesday, June 12, 2012 8:54 PM
Subject: Re: [kicad-users] Re: Comments About Eeschema


?

Nice. About this way i didnt think yet.

Here the circle is mostly used by old people from the times when
transistors in round thin cans were common. Is also a taste of
nostalgie.

Guilty as charged :).?? Actually I was taught that a transistor with a
ring was a discrete component, whereas without the ring it was part of
an integrated circuit.?? In practice since everything at that time was
hand drawn I think most engineers left off the ring (certainly I did).

Does the "envelope" (to use the IEC term) have to be conducting to
appear on the schematic??? Historically I think most transistors and
valves had non-conducting envelopes (eg OC45, ECC83) but they all had a
ring around them on the schematic.?? It would seem that valves still do
so in the standard (and they would look messy without a ring), but not
all transistors.?? However, a search on the official term "envelope"
reveals S00061 and the seemingly identical S00062, suggesting (since the
document shows primitives, not just complete symbols) it *is* allowed to
place a ring around anything.?? S00064 suggests it's also allowed to use
a dashed outline as in my BS817DS symbol.?? Being an old fogey I'm
minded to stick with the ring in symbols I create as it keeps the
symbols consistent.?? If some young whipper-snapper wants to remove them
they would be free to do so (though I reserve the right to suck air
through my three remaining teeth).

The copy of the standard I found using Baidu is 2001, BTW, so later than
yours.

Regards,

Robert.
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________________________________
From: Bernd Wiebus <bernd.wiebus@...>
To: kicad-users@...
Sent: Tuesday, June 12, 2012 7:51 PM
Subject: Re: [kicad-users] Re: Comments About Eeschema


?
Hello Robert.

I will shrink
some components, so perhaps I should postfix the components with _SMALL
to eliminate clashes.?? Mainly I'll be shortening pin lengths.

Yes, i used this postfix method in my first attemp to create a library
when i noticed that my symbols were much too big......

Is it OK in IEC60617 to have circles around transistors??? I notice that
a circle is included when one of the electrodes is connected to the
envelope (and then you're supposed to show the connection with a dot),
but what about where there is no connection?

Of course, EN60617-5 contains as No. 05-05-02 only one example of a
transistor encapsulated with a circle for a housing and a dot for the
connection.

Furthermore EN60617-5 is modular, so it contains a lot of symbols of
typs of electric channels, intrinsic zones, multilpe gates and so on.
So you can create your fitting symbol for your transistor or diode.

But EN60617-5 contains no example of a single transistor housing as a
symbol....this circle just exist in this exampleNo. 05-05-02.

So No. 05-05-02 should not exist, or it implicides, that a circle is a
symbol for a (conductice) housing.

No. 05-07-01 and No. 05-07-02??do not fit in this system, too, because
they are symbols for a tube envelope, which can be steel, but used to be
glass or ceramic.

Now i am thinking about canceling the circles in the library. I used
them only for classic pipolar transistors. Theoretikal there should be
three alternative symbols for every transistor type: one without
housing, one with housing, but not connected, and one with a housing
connected to the collector (but what is with emitter connected
housings?) So it would be a bulky library with many seldom used symbols.
And i think, exactly this is the reason why the EN60617-5 is
modular.....

Today transistors with shielded housings are very uncommon. So it is
better to cancel the housings, and the few cases, where a housing is
importand, have to draw an extra circle around their transistors and tie
it where it fits.

?? I like having the circle because it shows at a glance that the part
has its own package, and by making part of the circle dashed one can
show at a glance that the tcomponent shares its package with other
devices (and therefore there will be fewer packages on the board).
By
way of example?? I've attached an image showing my own symbol for a
BC817DS, for which Yahoo Groups should provide a link.

Nice. About this way i didnt think yet.

Here the circle is mostly used by old people from the times when
transistors in round thin cans were common. Is also a taste of
nostalgie.

By the way: My EN60617-5 here, which is from 1996 and active, contains
44 pages. 3 pages pr?ambel, 15 pages about semiconductors and 26(!)
pages about tubes(!). ;O)

With best regards: Bernd Wiebus alias dl1eic

Hi Bernd,

Thanks for your responses. I went through the KiCAD posts looking
for discussions on grid sizes; it looks like EESchema will retain the
mil grid (in all the posts I can find regarding grids, the devs say
they have no plans to change the schematic grid since there is no
great advantage to this). So I was mistaken; symbol standardization
can go on with the mil grid. This does result in larger symbols
though since nodes are at 2.54mm rather than 2.0mm.

________________________________ From: Bernd
Wiebus<bernd.wiebus@...> To: kicad-users@... Sent:
Tuesday, June 12, 2012 4:08 AM Subject: Re: [kicad-users] Re:
Comments About Eeschema



Hello Cirilo.

Have you seen Bernd Wiebus's EN60617 (aka IEC60617) kicad
library?



If it's correct (I have no reason to doubt that but I have
nothing to check it against, though maybe those Chinese sites
are worth exploring) I guess it would be a good place to start,
though personally I find Bernd's symbols too big. Is it the
latest standard?

Some of those symbols do comply with the IEC standard and many
that don't do comply with older standards.

If this is, it is marked by the symbols name. Thomething with
"old". In this cases, there are existing two symbols, one for the
old standard, ans one for the new. This is because here most people
like the old timed full black inductance boxes.....

But there are some "needfull things" among those EN60617 symbols,
wich are not EN60617, but this are normally not electronic devices,
with the exeption of "wire bridges". If desired, i could split this
library in two and purify the EN60617 part.

I suspected some people wanted older symbols; personally I think some
of the older symbols are prettier and for me they're easier to
understand. It would be good to keep the EN60617 compliant symbols in
their own directory+library since that will help a lot with the
standardization process and in the future if people have requirements
to use a specific symbol set it makes it easier for them to comply.

Anyway, as I said, what's important is that people can read the
schematics.

I think Bernd's symbols can't really be shrunk much more;

EN60617 makes no statements about the aspect ratio of symbols
(means wether a resistor "box" is lean or fat and something like
this). And for kicad i should not go away from the 50-50 raster for
easily drawing circuits without jumping into the engin room and
changing the raster.

That's one of the situations common with standards (lack of
implementation details). In this case it just means choosing your
own settings based on what looks good and is easy to read; the grids
used might impose some restrictions on what you can draw and that may
be one reason the aspect ratio is not specified.

I'd say his symbols are OK, certainly usable, but most can be
improved (for example, the purists will howl about the line
connecting the vertices of the inductor symbols - and rightly
so). The problem as usual is time; building a good symbol set
takes an awful lot,

Yes. This is a time problem. But there are some other points
counted against creating a "new" library. And this is to be
compatible with older versions of this library. If i change them to
much, people will see gaps if the new symbols do not fit to the
same connections as the old do. This may not be an issue for an
experinenced kicad user, but for an necomer.

I agree 100%. I was thinking there would be a metric and a mil set
of symbols, but for now it looks like EESchema will retain the mil
grid.

and at this point in time I'd recommend waiting for KiCAD to go
metric (internal units = nanometers) before spending time
building up standard symbols. However, if you look at the symbols
which come with KiCAD, very many (I can't say 'most' because I
haven't looked through the set and counted the bad ones) are not
only non-compliant with the latest IEC specifications, but I
don't recognize the symbols as IEC, IEEE, or ASME - some of the
symbols are such poor caricatures of standard symbols that they
will actually make a schematic difficult to read.

This is because there is not only a mixing between IEC, IEEE, ASME
ec. but with different ages of this librarys, too.

What I would like to see in the future is a standards-compliant
symbol set for KiCAD. This can start with an IEC60617 directory
with libraries classified according to form or function - that
alone will give us many of the symbols we typically use - and
then people can contribute other symbols but those symbols will
need to be vetted before they're put into the library tree; once
you head down the path of standardization you really can't afford
any compromise - any symbols which have not been vetted will have
to go into a 'non-standard' directory branch.

Ok.

This is all somewhat academic at the moment. KiCAD is certainly
usable as it is and although it would be great to start
implementing improvements, KiCAD also happens to be in a state of
development where it's probably best to hold back on making those
improvements.

The actual version of my EN60617 Library is RefE4. So send me your
suggestions for improvement.

With best regards: Bernd Wiebus alias dl1eic

Thanks Bernd, for now I can't really comment since I don't have a
copy of the specifications or a current subscription to the database;
my previous comments such as the one about the wire crossing the
vertices of the inductor symbol was based on what I remember of
specifications ca. 1998. I think for now, just keeping the standards
compliant symbols separate from the others and with perhaps a note in
the directory to give the name of the reference document is a good
step. Hopefully in about a year I can put some effort into building
and checking symbols.


- Cirilo



------------------------------------

Please read the Kicad FAQ in the group files section before posting
your question. Please post your bug reports here. They will be picked
up by the creator of Kicad. Please visit for
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library. For building Kicad from source and other development
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________________________________ From:
Robert<birmingham_spider@...> To: kicad-users@...
Sent: Sunday, June 10, 2012 8:00 PM Subject: Re: [kicad-users] Re:
Comments About Eeschema



Have you seen Bernd Wiebus's EN60617 (aka IEC60617) kicad library?



If it's correct (I have no reason to doubt that but I have nothing
to check it against, though maybe those Chinese sites are worth
exploring) I guess it would be a good place to start, though
personally I find Bernd's symbols too big. Is it the latest
standard?

Regards,

Robert.

Hi Robert,

Some of those symbols do comply with the IEC standard and many that
don't do comply with older standards. Anyway, as I said, what's
important is that people can read the schematics. I think Bernd's
symbols can't really be shrunk much more; I'd say his symbols are OK,
certainly usable, but most can be improved (for example, the purists
will howl about the line connecting the vertices of the inductor
symbols - and rightly so). The problem as usual is time; building a
good symbol set takes an awful lot, and at this point in time I'd
recommend waiting for KiCAD to go metric (internal units =
nanometers) before spending time building up standard symbols.
However, if you look at the symbols which come with KiCAD, very many
(I can't say 'most' because I haven't looked through the set and
counted the bad ones) are not only non-compliant with the latest IEC
specifications, but I don't recognize the symbols as IEC, IEEE, or
ASME - some of the symbols are such poor caricatures of standard
symbols that they will actually make a schematic difficult to read.


What I would like to see in the future is a standards-compliant
symbol set for KiCAD. This can start with an IEC60617 directory with
libraries classified according to form or function - that alone will
give us many of the symbols we typically use - and then people can
contribute other symbols but those symbols will need to be vetted
before they're put into the library tree; once you head down the path
of standardization you really can't afford any compromise - any
symbols which have not been vetted will have to go into a
'non-standard' directory branch.


This is all somewhat academic at the moment. KiCAD is certainly
usable as it is and although it would be great to start implementing
improvements, KiCAD also happens to be in a state of development
where it's probably best to hold back on making those improvements.

- Cirilo

On 10/06/2012 00:04, Cirilo Bernardo wrote:

________________________________ From:
Robert<birmingham_spider@...> To:
kicad-users@... Sent: Saturday, June 9, 2012 7:15
PM Subject: Re: [kicad-users] Re: Comments About Eeschema



I'm not sure what is the intention of this thread but please
remember that kicad is international and these are all US
standards. Component annotations are almost certainly
governed by an ISO standard.

Regards,

Robert.

Sure, but many of the ASME standards were transferred to IEC and
some later became an ISO standard - but having said that, many of
the symbols people created for EESCHEMA do not comply with
standards. For example, the MOSFET with a symmetric gate -
standards documents dating over 35 years ago were recommending
the asymmetric gate symbol and personally when I see a symmetric
gate symbol I want to hit someone with a large book. This is not
really a problem because people can still understand the
drawings. However, it's a good idea to move towards standards
compliance. On the down side, I think the best way to proceed is
to have a working group who spends time making up a new set of
compliant symbols, including existing symbols after confirming
that they comply with standards, and checking symbols other
people submit. This is not a small job; it's something I
wouldn't mind doing, but at the moment all my free time is going
into the 3D solid

model

issues which I believe is of far more value to users at the
moment than standards-compliant symbols. However, regarding the
comments on standard reference designators - that's something
which should be brought into conformance as part of the process
of making KiCAD a top quality tool.

- Cirilo

On 09/06/2012 07:14, Lawrence wrote:

John, I have been able to find the IEEE and ASME standards
online on the Internet. They are usually in PDF and some may
be freely downloaded for non commercial usage because they
are copywrited material. --For IEEE 315-1975 (R1993) "Graphic
Symbols for Electrical and Electronics Diagrams (Including
Reference Designation Letters)" see message number 11068 to
see where to go to get a PDF copy that can be downloaded.
This standard was withdrawn by ANSI as an American National
Standard (ANS) as of June 2004. The IEEE has this as an
active standard but there has been no activity on it since
being reaffirmed in 1993. --For ASME Y14.44-2008 "Reference
Designations for Electrical and Electronics Parts and
Equipment" I went to a Chinese Website<www.> and
ended up at<www.doc88.com/p-6030462696.html>. This is
viewable and maybe can be downloaded but the process is not
straight forward. --For ASME Y14.34-2008 "Associated Lists" I
also went to the Chinese Website<www.> and ended
up at<www.doc88.com/p-5990462641.html>. Again, this is
viewable and maybe can be downloaded but the process is not
straight forward.

Regards, Larry 9V1/WN8P

--- In kicad-users@..., John Hudak<jjhudak@...>
wrote:

LOL, well said! (I am not a developer in this effort, but
have been on others). I've often wondered this myself.
Having seen this lack of attention to standards in other
open src tools, I can guess at many reasons, ranging from
ignorance to arrogance to cost (acquiring some of those
standards requires real money). In many cases, there is
quite a lot of overlap between IEEE/ANSI/IEC/CENELEC etc.
OTOH, I am thankful for the tool.... I am very interested
in the response..... -John


On Wed, Jun 6, 2012 at 10:37 AM, Lawrence<lawrence_joy@...>
wrote:

**


To developers of Kicad and others. Comments about
Eeschema.

--Why are the X,Y coordinates upside down in the Y axis?
When I learned Cartesian coordinates the abscissa (X
axis) has positive values going to the right and negative
values going to the left with the ordinate (Y axis) with
positive values going up and negative values going down.
Quadrant I would have the 0,0 point in the lower left
corner. Do they teach this differently in Europe? It is
very confusing to me.

--Terminology for reference designators: A basic
reference designator has a class designation letter(s)
and a number. Class designation letters are 1, 2, or 3
letters, but if 3 letters are used the 1st letter will be
X as in XDS or XAR. For the complete reference designator
A1R7, the A1 is called the reference designator prefix
and for the complete reference designator A1PS1C3, the
A1PS1 are called reference designator prefixes. The Unit
Numbering Method of assigning reference designators is
covered by ANSI/ASME Y14.44-2008 (used to be ANSI/IEEE
200-1975).

--I have seen in many messages the term "multi-part
component" used. The terminology I know is
"mulple-element part" and is covered in ANSI/ASME
Y14.44-2008, Clause 2.1.4 Suffix Letter.

--The terminology I know calls a listing of parts a
"parts list (PL)" and is covered by ANSI/ASME
Y14.34M-2008 Associated Lists. In this standard it is
stated that "bill of material" is an obsolete term.

Just some ramblings.

Regards, Larry 9V1/WN8P

------------------------------------

Please read the Kicad FAQ in the group files section before
posting your question. Please post your bug reports here.
They will be picked up by the creator of Kicad. Please visit
for details of how to contribute your
symbols/modules to the kicad library. For building Kicad from
source and other development questions visit the kicad-devel
group at !
Groups Links





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------------------------------------

Please read the Kicad FAQ in the group files section before
posting your question. Please post your bug reports here. They
will be picked up by the creator of Kicad. Please visit
for details of how to contribute your
symbols/modules to the kicad library. For building Kicad from
source and other development questions visit the kicad-devel
group at ! Groups
Links





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------------------------------------

Please read the Kicad FAQ in the group files section before posting
your question. Please post your bug reports here. They will be picked
up by the creator of Kicad. Please visit for
details of how to contribute your symbols/modules to the kicad
library. For building Kicad from source and other development
questions visit the kicad-devel group at
! Groups Links




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