add LT3015Q

[aewallin]

LT3015Q adjustable negative low noise voltage regulator in TO-263-5 package.

datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/3015fb.pdf

Screenshot:

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• Provide a URL to a datasheet for the symbol(s) you are contributing
• An example screenshot image is very helpful
• Ensure that the associated footprints match the official footprint library
• If there are matching footprint PRs, provide link(s) as appropriate
• Check the output of the Travis automated check scripts - fix any errors as required

[myfreescalewebpage]

Hi @aewallin, thanks for contributing,

Looks great, maybe you can enlarge a little bit the symbol vertically between pins SHDN/VIN and ADJ/OUT. @antoniovazquezblanco @DanSGiesbrecht what do you think about that ? Else, ready to be merged.

Cheers,
Joel

[aewallin]

We almost always use LT3015 (this one) together with LT1963 (PR #1169) - IMO best to make the symbols similar.
If the symbol shape is agreed on I can add these v-regulators in fixed-voltage output format and other footprints also.

[myfreescalewebpage]

@aewallin I agree we should treat both PR at the same time, I have the same remark about the size of the symbol for PR #1169.

Just adding below an example (LT3010) of what I mean by enlarging a little bit the symbol. This is to get a better consistency between symbols.

This will also permit to fix KLC error S3.1 (travis output)

[myfreescalewebpage]

@aewallin can you fix the footprint filter to TO?263?5* ?

[evanshultz]

Footprint filters should not have pin count, so don't include the ?5 part. Furthermore, use asterisks instead of question makes wherever possible and that applies to all instances here. Note that I haven't looked at anything else but the last comment.

[myfreescalewebpage]

@evanshultz ok. @aewallin so keep the footprint like that for that PR.

[aewallin]

fp-filter changed.
box enlarged.
library seems inconsistent on negative voltage regulators: to have Vin/Vout at bottom and GND at top, or like positive regulators Vin/Vout at top and GND at bottom. now using latter approach.

[myfreescalewebpage]

library seems inconsistent on negative voltage regulators: to have Vin/Vout at bottom and GND at top, or like positive regulators Vin/Vout at top and GND at bottom. now using latter approach.

Not sure it's very convenient to draw the schematic now, or maybe you can provide a screenshot. You're right the library is not consistent, I think I prefer the opposite, with GND pin at the top. Reference at the bottom left corner, name at the bottom right corner. This will make a KLC error, @antoniovazquezblanco @evanshultz what is your opinion ?

Joel

[aewallin]

maybe you can provide a screenshot.

The two styles I was thinking about are below. Maybe it is best to have symbols KLC-compliant with GND down, and the user can flip with X/Y as appropriate for the schematic.

GND-down style on +v and -v:

GND-up on -v, with a symmetryc drawing for a bipolar supply:

[myfreescalewebpage]

@aewallin agreed with you I have forgotten X flip possibility and just made a try. Your proposition sounds good and it respects the KLC so that's also very nice !

@aewallin also just checked other symbols, according to me ADJ should be Input, not Passive.

[aewallin]

@myfreescalewebpage Looking at examples from the current regulator_linear library it looks like some ADJ/SENSE/FB pins are marked Passive, and some are marked Input.

Any opinion on this from a Librarian - I'll change the ADJ pin type here and in #1169, if there is consensus.

[myfreescalewebpage]

Any librarian about ADJ pin type question ? Thanks.

[antoniovazquezblanco]

@KiCad/librarians question above, please :)

[Misca1234]

Even if older merges is different I would argue to follow the data sheet,
according to page 14,
SHDN should be input
SENSE should be input

[DanSGiesbrecht]

I think that either passive or input is suitable for ADJ. I have seen it argued that it should be passive because you could feed it with a resistor-divider, but this wouldn't generate an ERC warning if the pin was an input. This could be suggested to be formalized in the KLC.

[Misca1234]

yes, the ERC .....

[aewallin]

after changes:

[poeschlr]

Regarding pin types: we are working on setting up an algorithm for determening which type to use. See KiCad/kicad-website#342

[Misca1234]

I am happy with this little gem, any objections ?

[poeschlr]

Not from my side. As there are already so many reviews i am going to assume this is ok and simply merge. Thanks @aewallin for your great work here.