Hi everybody,
It’s my first time using Kicad and my first time making an schematic as well. I run through a few errors when I do the electrical rules check, I hope you can help me.
Also, if you think I have done a poor design, I’m missing something or if you see some other errors I would like to know about it. Thanks in advance!!
Find attached the schematic.
You’ll want to include the -cache.lib file as well.
This is the _cache.lib file.
The symbol information is not included inside the schematic file(s) itself at this point in time. The cache lib is what takes care of that. Without it one requires the reader to have the exact same library setup as one will otherwise get unexpected results like changed symbols (without notification) or even question marks.
In short: Consider this file to be part of the schematic.
It is a cache of the graphics and pin definitions (basically the parts of a symbol that you can’t edit in the schematic editor) used for all the symbols used in the schematic.
Until V6 (couple years out) when the contents of the cache file will be part of the schematic file, yes you should nearly always share it with the schematic file.
The only possible exception is if you know for a fact that both you and the person you are sharing with use the same library nicknames and contents. But even on one’s own computers this can be difficult to maintain, so it is best to consider both the files required for sharing a schematic.
The main issue that KiCad is flagging is that you are not powering your LEDs. You have capacitors between the power line and the input power to your LED. This may work for a quick flash (Impedance goes down with frequency) but you have these on a DC line, so KiCad is correctly saying that your power inputs don’t have power.
Thanks @Seth_h, I added a power flag to each VDD and it solved the problem.
What about the problem related to the MOSFET?, it says:
Pin 5 (Power output) of component J3 is connected to pin 2 (Bidirectional) of component Q1 (net 34).
That’ll fix the ERC but I doubt it will make your circuit work. DC power doesn’t flow through capacitors (to first order).
This is a warning. It’s letting you know that you may have made a mistake. In this case, I’d say that your symbol incorrectly identifies the class of the pin. It should not be “Bi-directional”, instead it should be “Passive”. Bi-directional pins are more properly used for MCU pins that provide DIO.
Ok, I haven’t looked at your schematic, but based on both Seth’s and your descriptions, all you did was remove the ERC error. If you have a capacitor inline with the VDD pin of a component, the only time that component will see voltage is very briefly (way less than 1 second) with power is first applied. Then the capacitor will be charged and not let any current “flow” through it.
If (as I suspect) those capacitors are for decoupling (noise resistance), they shouldn’t be between the VDD pin and the power source. They should bridge from the VDD pin to ground right next to your device, still allowing the connection between the VDD pin and the power source.
I see, like in this schematic?http://archive.fabacademy.org/archives/2016/fablabaalto/students/294/articles/output-devices/img/sk6812_typical.jpg
Yes. That’s the schematic from the LED’s datasheet. It is hopefully correct (I haven’t tried one of these smart LEDs)
Thanks!, I just changed it.
What about the Q1 issue?
Someone also said this
you’re getting about 100mA out of the USB port depending on what you plug it int
I’m not sure what he meant
You should ask them.
You should ask them.
I know, I just wanted feedback from different sources, if it doesn’t make sense to you, I’ll asume the battery charger schematic is fine.
This is a warning. It’s letting you know that you may have made a mistake. In this case, I’d say that your symbol incorrectly identifies the class of the pin. It should not be “Bi-directional”, instead it should be “Passive”. Bi-directional pins are more properly used for MCU pins that provide DIO.
I edited the symbol to be a passive connection and it works fine now, I didn’t get any error
Thanks for your help guys!!
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