What does it mean? A programm to convert V5 libs to V4, the converted V5 libs to V4 or something else?
I think, now you know how to do it, but…
If you have small filled zone as at the pictures you show and IC pads are connected directly to them then you have no problem with hand soldering it. If you have a big GND zone on top and pads connected directly to it you can have a problem to hand solder it. I suppose I would have to use my 110W trafo soldering iron to solder this grounded pads in such situation which is not enough precision iron as for SMD. If you dissipate 50% of max IC power you need not to be so serious about heat. But it is you who know sach things.
We will release a version of the v5 lib where we remove footprints and symbols that can not be used in kicad version 4. So this lib will lack a few footprints and symbols but most of them will be there.
- It will lack all footprints that include any of the new pad types.
- It will also lack some symbols who use pin numbers with more than 4 characters.
- Another limitation will be in the footprint filters as kicad 4 can not handle filters that include the library name. (So these symbols will not be as useful in kicad 4 compared to kicad 5 but can still be used)
The intention is that users use this backported lib for their new projects until they switch over to v5. This will allow these projects to be easily converted to the new lib structure. (As it already uses the new structure)
In essence we want to make the transition period as painless as possible for the users.
I suppose no problem with footprint libraries, but if symbol libraries in V5 would be organised like footprint library in V4 (I don’t know but suppose such change) users who use their own libraries will need a tool to konvert their libraries (or Library editor could load V4 library and save it as V5).
V5 can open v4 libs without any problem. The other way round however is not possible. (v5 still uses the same basic file format but added a few things and dropped some restrictions.)
The only thing users need to do after updating to v5 is add their libs to the library table and remap their projects. (opening a v4 schematic in v5 will open the so called remap dialog. This function will transfer a project over to v5. Meaning it can then never again be opened in v4)
I noticed in 4.0.7 the file KiCad\share\kicad\template\sym-lib-table. I think there were no that file in 4.0.6 and that file looks for me as being not used. This suggested me that sym libs are going to be changed to be organised as footprint libraries - one disk file=one symbol.
I like such organisation. I need not to think each time how to move one element from one library to another. I just copy file on disk and vouala - done. I am working that way with footprint libraries. I selected KiCad footprint library set that contains potentially interested elements. Changed all their naims by adding “Z_” at the begining (in some widows libraries are in designed by me order, but in some in alfabetic order. I have prepared directories for all my libraries and add them to the list. If I need new footprint I copy one file from one Z_xxxx directory and edit it in my library.
Rotate the capacitors 90 degrees, so the GND pad is nearer to the DND pads of U3.
I’m new to Kicad as well. From what I’ve learned I would approach this by copying an existing footprint then modifying the copper pads to meet your needs. As for how to do this I’m not good enough yet to give you blow by blow instructions. I only stumbled through it myself, but to start open the footprint editor, find your current footprint and copy it to a different library (likely one associated with you project).
Regarding the thermal considerations:
The goal of the larger copper pads are to conduct some of the heat into the air. Air is such a poor conductor of heat that the solder mask has a trivial effect.
The via’s are plated with a very thin layer of copper, so each via does not conduct so much heat. Larger via drill sized and more vias can help. I’ve heard conflicting opinions on the thermal effect of filling a via with solder.
Hope this helps.
BTW Because air is such a poor conductor of heat, the majority of the thermal energy will result from air currents created by the copper being hotter than the surrounding air (hopefully) and moving the heat away as the currents move. Consider other components in the area that can block these air currents. This assumes you are really pushing the thermal design.
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In this entire thread no one has known what input and output voltages are to be; nor the expected current draw required of the output. There are now 28 replies, and no real way to answer this question without knowing how many Watts the device is expected to dissipate in voltage drop regulation and output current.
…and I’m not even a paper applied engineer.
Yet, the OP figures the design requires an isolated DC to DC converter with “up to” 31% efficiency?
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Sprig. The maximum load capacity on the datasheet is 0.9W of thermal dissipation from the chip with 45C/W thermal resistance to air before you add zones.
If you dont know something. You work off the worst case. Thats just engineering. The chip will work in most applications at 40C above ambient. And where it needs to be cooler he would increase the zone area.
If he wanted to know how much area he would need for a given temperature rise, that is an online calculator away from the answer.
P.s. can you really call yourself an engineer until you know how to operate a steam engine?
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@Rerouter You totally missed my point.
With the information presented up to now, none of us know if the power requirements of the design exceeds the capabilities of the part, or it’s mounting configuration.
That variable is missing, and noticing that is what I’m very good at. I noticed it, it appears that none of the previous replies did.
Without knowing the output voltage selected and the expected current source, not any one of the prior replies are based on this specific circuit design.
What if the OP’s design uses 5V in and requires 3.3V out with 85mA of current?
I understand your point. I find many questions perplexing. Like this case, how does one get to this level of a board design without understanding capacitor placement. Here I assume there are more folks involved who are responsible for the detained design. So I try to answer the asked question without getting too far into the details.
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Is “Thermodynamics” even required these days as a core course for all engineering disciplines?
Dale
That’s not what the OP asked.
Maybe you should go back and review those 28 posts. 
He is using 5V in, and he is using 3.3V out, and 85ma would be just fine. Seems you’re the only one in the dark here. The rest of us knew that back on post 8.
There is a lot more to laying out a PCB than simply connecting nets.
OkyDoky, If I have to ANALYZE a screen shot of PcbNew Footprint Nets, I still don’t know what the expected current draw will be.
And, you yourself, might want to re-read the DataSheet and “run” the numbers for the device with 85mA of output current; even though the expected output current still remains a mystery.
But you are very good at noticing things like that.
Feel free to ask him but all of the advice given in this topic has been based on the max capacity of the device, a reasonable approach, space permitting, regardless of his requirements.
What would you like to know? The combination of 5V in and 3.3V out is rated for 100ma of output current at aprox. 26% efficiency, 250ma of input current and about 910mw total dissipation.
If it’s only 26% efficient, wouldn’t it be better to use a linear regulator in this case?
The ADuM6000 is an isolated DC-DC converter. Without knowing more about the OP’s application we can only assume the isolation is a requirement. Even so there would be far more efficient discrete SMPS solutions but they would require a transformer. The ADuM6000 is rather expensive but it does provide a small, simple solution for an isolated DC supply.
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Looking at OP’s previous thread I suppose it as a kind of student task.
Years ago I considered using AD isoPower ICs but when I sow the appnotes how to use it and not violate EMC I gave up.