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Re: Checking the schematic by SPICE simulation

 

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.

--
Signature OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com





Re: Fixing holes

 

When I add Test Points I add a part number for the type I want and I use GRN for Ground, BLK for Digital Ground, RED for Voltages, YEL, and BLU for various other signals...??
When I add 2-Pin Jumbers I add a separate schematic symbol and part number for the Shunt...? I have my own color code for those too...
You could add a part number for a hole so you would remember to buy screws or have a separate symbol for screws, washers...
Same for stand-offs or other hardware items...
I typically have all of those hardware items on the last page of my schematic...? This makes it easy to open a previous schematic and cut-n-paste them into the new design...? ?

73 Dallas N4DDM
CQ Field Day, CQ Field Day


Re: Fixing holes

 

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I didn't know that. I've never seen it, but now I will look for it.

On 2024-06-21 17:52, Jon Escombe via groups.io wrote:
Perhaps worth noting that there is also MountingHole footprint library. You'll find a number of standard metric hole sizes already in there..

Regards,
Jon

On 21/06/2024 17:38, John Woodgate via groups.io wrote:
Thank you. I can understand that.

On 2024-06-21 17:07, Robert via groups.io wrote:

The second paragraph is "Footprint pads".?? You just need to create a
single through-hole pad of the correct dimensions.







--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

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I will study the guide again.

On 2024-06-21 17:07, Robert via groups.io wrote:
There's a guide in the getting started guide:



If you just want a simple bolt hole, nothing fancy, use a single pin
connector as the schematic symbol, connect it to a net or not as
required, and skip down to:



The second paragraph is "Footprint pads".?? You just need to create a
single through-hole pad of the correct dimensions.

Once you have your footprint saved, you can go back to the schematic
symbol and select it in the symbol properties.

Regards,

Robert.

* Plain text email - safe, readable, inclusive. *





--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

Perhaps worth noting that there is also MountingHole footprint library. You'll find a number of standard metric hole sizes already in there..

Regards,
Jon

On 21/06/2024 17:38, John Woodgate via groups.io wrote:
Thank you. I can understand that.
On 2024-06-21 17:07, Robert via groups.io wrote:

The second paragraph is "Footprint pads".?? You just need to create a
single through-hole pad of the correct dimensions.


Re: Fixing holes

 

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I made a note, but I didn't buy. Now I have bought (not without difficulty, but that's life).

On 2024-06-21 17:06, Alan Pearce via groups.io wrote:
You should seriously get the ebooks I mentioned in one of my previous posts, it will take you right through all these aspects, and be a reference for the various questions.


On Fri, 21 Jun 2024 at 16:52, John Woodgate via <jmw=[email protected]> wrote:

Would that I had your depth of knowledge!

On 2024-06-21 16:47, Tony Casey wrote:
Exactly so. I include mechanical things like fixing holes, RF screens, and the PCB itself in the schematic as parts.

--
Regards,
Tony


On 21/06/2024 17:24, Robert via wrote:
A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.
--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying


Re: Fixing holes

 

开云体育

Thank you. I can understand that.

On 2024-06-21 17:07, Robert via groups.io wrote:
There's a guide in the getting started guide:



If you just want a simple bolt hole, nothing fancy, use a single pin
connector as the schematic symbol, connect it to a net or not as
required, and skip down to:



The second paragraph is "Footprint pads".?? You just need to create a
single through-hole pad of the correct dimensions.

Once you have your footprint saved, you can go back to the schematic
symbol and select it in the symbol properties.

Regards,

Robert.

* Plain text email - safe, readable, inclusive. *





--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

There's a guide in the getting started guide:



If you just want a simple bolt hole, nothing fancy, use a single pin
connector as the schematic symbol, connect it to a net or not as
required, and skip down to:



The second paragraph is "Footprint pads". You just need to create a
single through-hole pad of the correct dimensions.

Once you have your footprint saved, you can go back to the schematic
symbol and select it in the symbol properties.

Regards,

Robert.

* Plain text email - safe, readable, inclusive. *


Re: Fixing holes

 

You should seriously get the ebooks I mentioned in one of my previous posts, it will take you right through all these aspects, and be a reference for the various questions.


On Fri, 21 Jun 2024 at 16:52, John Woodgate via <jmw=[email protected]> wrote:

Would that I had your depth of knowledge!

On 2024-06-21 16:47, Tony Casey wrote:
Exactly so. I include mechanical things like fixing holes, RF screens, and the PCB itself in the schematic as parts.

--
Regards,
Tony


On 21/06/2024 17:24, Robert via wrote:
A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

We didn't place fixing holes, but do place the screws that go in them as a mechanical component (same as the PCB itself, so they appear on the BOM and get kitted). This then required a pad for the component, which was just a single pad, with hole of suitable size, and copper pad top and bottom of desired. A suitable keep out around the hole to handle any washer, solder lug, or anything else that may go under the screw head, or just for the area the screw head would cover completes the pad.



On Fri, 21 Jun 2024 at 16:47, Tony Casey via <tony=[email protected]> wrote:
Exactly so. I include mechanical things like fixing holes, RF screens, and the PCB itself in the schematic as parts.

--
Regards,
Tony


On 21/06/2024 17:24, Robert via wrote:
A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.


Re: Checking the schematic by SPICE simulation

 

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Thank you. I will investigate whether I can work on it in the SPICE environment.

On 2024-06-21 16:53, Alan Pearce via groups.io wrote:
I believe the most recent version (which I believe is what you are using) of kicad can export to LTspice. I haven't tried it but presume there is a specific export section in the file menu, least that is where I would expect to find it.


On Fri, 21 Jun 2024 at 16:05, John Woodgate via <jmw=[email protected]> 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.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.
--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying


Re: Checking the schematic by SPICE simulation

 

I believe the most recent version (which I believe is what you are using) of kicad can export to LTspice. I haven't tried it but presume there is a specific export section in the file menu, least that is where I would expect to find it.


On Fri, 21 Jun 2024 at 16:05, John Woodgate via <jmw=[email protected]> 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.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

开云体育

Would that I had your depth of knowledge!

On 2024-06-21 16:47, Tony Casey wrote:
Exactly so. I include mechanical things like fixing holes, RF screens, and the PCB itself in the schematic as parts.

--
Regards,
Tony


On 21/06/2024 17:24, Robert via groups.io wrote:
A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

开云体育

Thank you, but I need a more elementary guide, step by step.

On 2024-06-21 16:24, Robert via groups.io wrote:
A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.

Regards,

Robert.

* Plain text email - safe, readable, inclusive. *





--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: Fixing holes

 

开云体育

Exactly so. I include mechanical things like fixing holes, RF screens, and the PCB itself in the schematic as parts.

--
Regards,
Tony


On 21/06/2024 17:24, Robert via groups.io wrote:

A hole is just a single pad of the correct dimensions.?? It can have
copper layers, or none (in which case it becomes a non-plated through
hole).?? If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes).?? In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol.?? Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements).?? I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.


Re: Fixing holes

 

A hole is just a single pad of the correct dimensions. It can have
copper layers, or none (in which case it becomes a non-plated through
hole). If it has copper layers, they can optionally be connected to
any net (usually the ground plane, and typically with no thermal
spokes). In the past I just defined the hole on the schematic with a
single pin connector, but these days I have my own symbol. Often the
associated footprint that I create will define a board outline and all
the holes (as pads), and typically much more (such as silk screen
elements). I routinely import that from mechanical CAD as a DXF.

So there are no hard and fast rules - you just do whatever cranks your
tractor on the day.

Regards,

Robert.

* Plain text email - safe, readable, inclusive. *


Checking the schematic by SPICE simulation

 

开云体育

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.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Fixing holes

 

开云体育

I have an old advice sheet about how to add fixing holes to a board, but both methods are really work-arounds and have disadvantages. I am a bit surprised that this issue is not documented (as far as I can find). Advice would be welcome.

--
OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

Virus-free.


Re: AVR64DB32 symbol

 

Hi Tom,

In the meantime, I created a ticket for the issue, and prepared a patch. It has been accepted, and a pull request is created to fix the issue.

For your information, the project is a memory el-keyer.

73s de HA5OGL
Lev


On Tue, Jun 18, 2024, 03:02 Tom, KC2ZAT via <kc2zat=[email protected]> wrote:
Lev,
I've run into what you describe periodically.?

For the most part, I would probably make a quick copy of the similar part, change the name to the part you are using, and the pin direction, stick in a project specific library and call it a day.?

I? have also used/checked SnapEDA () when I need some of the newest parts.? They may already have it ready for download.

You need to check the download for the newest parts.? ?I was going to use a PIC part in a DIP-40 format.? When I was checking the setup, I discovered the DIP-40 download file actually contained the layout for the 44 pin surface mount part.

Overall, I have had good luck with snapeda.? Plus it frees up your cycles that can go to other tasks.
73
Tom, KC2ZAT?

On Jun 17, 2024 13:00, Lev <leventelist@...> wrote:

Hi all,



I am currently designing a new project using the relatively new MCU, the
AVR64DD32. I found that the DB version has the same pinout, and we have
symbol for it.

The REST/PF6 pin marked bidirectional, however the datasheet (and the
real device) states as input only. Is it wise and mark that pin input
only, so ERC can detect if that net is not driven?


Thanks,
Lev

--
Levente Kovacs
Senior Electronic Engineer

W:







Re: AVR64DB32 symbol

 

Lev,
I've run into what you describe periodically.?

For the most part, I would probably make a quick copy of the similar part, change the name to the part you are using, and the pin direction, stick in a project specific library and call it a day.?

I? have also used/checked SnapEDA (https://snapeda.com) when I need some of the newest parts.? They may already have it ready for download.

You need to check the download for the newest parts.? ?I was going to use a PIC part in a DIP-40 format.? When I was checking the setup, I discovered the DIP-40 download file actually contained the layout for the 44 pin surface mount part.

Overall, I have had good luck with snapeda.? Plus it frees up your cycles that can go to other tasks.
73
Tom, KC2ZAT?

On Jun 17, 2024 13:00, Lev <leventelist@...> wrote:

Hi all,



I am currently designing a new project using the relatively new MCU, the
AVR64DD32. I found that the DB version has the same pinout, and we have
symbol for it.

The REST/PF6 pin marked bidirectional, however the datasheet (and the
real device) states as input only. Is it wise and mark that pin input
only, so ERC can detect if that net is not driven?


Thanks,
Lev

--
Levente Kovacs
Senior Electronic Engineer

W: http://levente.logonex.eu