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Thanks, Andy, but to find 'a device in the same package' seems to me to be a step further away from searching through footprints for the one I hope is there. The part is a preset resistor, not a transistor.

isn't there a screen that shows descriptions and images of footprints?

However if you don't care about the actual device just find a device in
the same package, then copy it's footprint to your own lib and modify as
required.

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You typically search for the device, then you may see several footprints
with various names with e,b,c, b,c,e, 1,2,3, etc against then indicating
the different pinouts.

However if you don't care about the actual device just find a device in
the same package, then copy it's footprint to your own lib and modify as
required.

Andy



On Fri, 23 Aug 2024 15:20:29 +0100
"John Woodgate" <jmw@...> wrote:

What is the best way to search the hundreds of existing footprints for a
particular arrangement of pins? Just a 3-pin symbol, nothing complicated.

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What is the best way to search the hundreds of existing footprints for a particular arrangement of pins? Just a 3-pin symbol, nothing complicated.

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Do they not upgrade to the latest version? Anyhow, to answer your
question as best I can, I have copies of kicad going back to
kicad-2007-01-15.zip and KiCad-2008-08-25c-final-WinXP_autoinstall.exe
(both Windows). Unfortunately this only tells me the date, not the
version number. Can you tell me when your files date back to? Or
does anyone know how dates and version numbers relate?

Regards,

Robert.

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One, including the value, is to co-relate to the schematic, and might not obviously or unambiguously relate to the location. The other, the plain 'R14' located within the outline, is to show for certain which part goes there during assembly (population).

Hi,

I'm somewhat new to Kicad and PCB design for that matter.? When placing footprints on the PCB it seems that the Footprint Properties by default have both a "Reference Designator" and an unamed property who's value is ${RFERENCE} [screen shot attached] which seem to equate to the same thing on the resulting PCB [screen shot attached].? Are both of these needed?? I know I can turn off the "show" property for one of them -- but I'm wondering how they different, if both are actually needed, and if not is there a "bulk" update I can do to hide either one of them across all the footprints without having to click into each footprint?? ??

Thank you,
-richie

Hi,

In the Schematic editor, try Tools | Edit Symbol Fields...

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Hi,

I'm somewhat new to Kicad and PCB design for that matter.? When placing footprints on the PCB it seems that the Footprint Properties by default have both a "Reference Designator" and an unamed property who's value is ${RFERENCE} [screen shot attached] which seem to equate to the same thing on the resulting PCB [screen shot attached].? Are both of these needed?? I know I can turn off the "show" property for one of them -- but I'm wondering how they different, if both are actually needed, and if not is there a "bulk" update I can do to hide either one of them across all the footprints without having to click into each footprint?? ??

Thank you,
-richie

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On 22/06/2024 10:42, Andy wrote:

Just had a thought,
If you normally hide the power pins and have them auto connected, then
you can mirror the symbol which will flip the + and - locations.

If you have the power pins visible then they will also flip, but you
might be able to live with that.

For opamps and similar, I always draw alternate (de Morgan) symbols, for the different input pin configurations. Then you don't have to tolerate power pins being upside-down, if you flip the symbol. (I do exactly the same thing in LTspice.)

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Regards,
Tony

Just had a thought,
If you normally hide the power pins and have them auto connected, then
you can mirror the symbol which will flip the + and - locations.

If you have the power pins visible then they will also flip, but you
might be able to live with that.

Andy



On Fri, 21 Jun 2024 23:11:20 +0100
"John Woodgate" <jmw@...> wrote:

I expect you are right, and I'm into learning still, but it takes time
to grasp the nettle.

On 2024-06-21 23:07, Andy wrote:

Creating libs etc is very easy and moving things from one lib to another
is also easy. It's a task worth getting to know.

The EDR is not there to tell you that your design won't work, its to
ensure that your connection are all there.

I've never used the LTspice or Spice function of Kicad, but I do use LT
spice stand alone.

When I started, I did only one board with tape and dots.. Fortunately it
was a training exercise, and very shortly after we got an early PCB
layout system Racal Kadet I think. The layout techs would not let us
engineers near the thing, I think they thought (probably correctly) that
we would have it in bits to see what made it tick :-]

Andy





On Fri, 21 Jun 2024
22:10:37 +0100 "John Woodgate"<jmw@...> wrote:

I can accept all you say, but for my limited work I think that creating
new libraries is not justified. The point about the opamp is that the
EDR won't tell you that you have provided strong positive feedback
because you have not noticed that the + input is at the top. An .AC
might also not tell you, but a .TRAN would. My projects are now
'kitchen sink' - special test equipment, usually one-off, but when I
was in industry, 4000 would be a very modest run. In those days, it was
black tape on drafting film.

On 2024-06-21 21:46, Andy wrote:

Yes the pin positions are more common with -ive uppermost, but not
always.

The EDR cannot detect this because it in NOT an error it's just how
the symbol was drawn. It's down to the designer to connect the
components to the correct pin.

If you don't like it, then change the symbol...
I can't stand the American electrolytic symbol, so I change that to
the one that I've used for decades, the filled box for -ive and
unfilled for +ive

This highlights a VERY important point for ANY CAD system be it Kicad,
Eagle, Autocad, or any other design tool.

You NEVER use the provided symbols for live work. You ONLY use symbols
that you have checked and verified as good. These you save in your own
libraries and that's what you use when building your design on the
screen. It protects you from an unknown change being distributed to
the system that you don't spot, so when you use the part again you get
something different.

Not a problem on a single board "kitchen sink" project you just curse
at it, and bodge it. But if that happens on your 4000 board
production run you might be looking for a new job :-)

When you think about it, you only use a very small handful of
components in amateur projects so it does not take long to build up
your own libraries, and most of the provided ones will be perfectly
OK so it's just a matter of copying therm across to your own libs.


Andy



On Fri, 21 Jun 2024 16:04:18 +0100
"John Woodgate"<jmw@...> wrote:

As I understand it, I have to make a copy of the schematic and add
voltage sources (power and signal) and a load. Then add to that the
simulation command. But how do I introduce the models and subcircuits
for the active components?

What would be much easier for me is to be able to copy the schematic
into LTspice (as that is what I use) and do the simulation in that
environment. But is is possible to do that, i.e. can KiCad export a
schematic (or even a netlist) that SPICE understands?

This is important because it can be a costly mistake not to realise
that the KiCad opamp symbol has the + input uppermost, whereas it is
most common, I think, to see the - input uppermost. The EDR can't
detect that error, of course.

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Keep trying

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Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying