I'm currently trying to create the same thing that rrchips is, and I'm going to be using this circuit to create a PCB in Kicad. I have never made a PCB that I ever ended up printing, is there anyone who had this circuit sent out and successfully used it before? I'm going to upload a few screenshots of my project file so far, if anyone has any tips for a new Kicad user please let me know. Thanks!
I would prefer an AC opto coupler (double the input pulses available).
That only requires two parts, one LED current limiting resistor and the opto coupler itself.
Opto collector connected to the MCU pin, with internal pull up.
Could fit in a piece of heatshrink, no circuit board needed.
Leo..
I would choose much wider tracks...
There is enough space...
And keep the traces further apart.
This will be very difficult to solder...
And use a ground plane...
And turn the transistor 90 degrees.
Use through hole connectors with thick solder pads... these will easily come off... and you will not need a double sided print...
Or take Wawa's advice ...
Topic split from another topic. Please do not add your own questions to the end of other people's topics.
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Thank you.
D1 orientation is different between the track layout the cct diagram and the PCB.
Your PCB layout seems odd to me, and in some places, just incorrect. I've marked the problem areas in the image below:
A. Why are the tracks drawn as double, unfilled lines? It looks like you didn't use Kikad's dedicated wire routing tool, but simply draw the lines in a graphics editor...
B. Looks even worse. Why are the two wires running next to each other instead of merging into a single track?
(Latest correction) - I just realized that these wires go to different Q1 pins. In that case, of course, they certainly shouldn't be merged. But then it's strange to route them so close to each other, given that there's tons of empty space on the PCB.
C. The tracks aren't connected to the component pad.
D. The thin white lines indicate that you forgot to transfer some of the connections from the schematic to the PCB.
Overall, I forced to repeat - the PCB looks as if you didn't route them in Kikad, but drew these connections in a graphics editor.
It's quite obvious you don't understand the basic concepts of how to use a CAD tool to create a PCB. Read the documentation and do the tutorials. It will take a while before you become proficient.
I'd also say that you appear to be using the wrong footprint for the 2N3904. It looks like the emitter is connected to R3 instead of the collector.
Just to get you started and using your schematic:
I've put this board layout together. It could be much more compact but is close to your design. I've kept your SMD 3 pin header although through the hole (TTH) would be easier in this case, because you are free to connect traces to it from both copper layers, and it is more consistent with the remaining components. Blue tracks are on the bottom copper layer.
The components I selected are:
"Reference","Value","Datasheet","Footprint","Qty","DNP"
"C1","10nF","~","Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P2.50mm","1",""
"D1","1N4148","https://assets.nexperia.com/documents/data-sheet/1N4148_1N4448.pdf","Diode_THT:D_DO-35_SOD27_P7.62mm_Horizontal","1",""
"J1","Screw_Terminal_01x02","~","TerminalBlock:TerminalBlock_bornier-2_P5.08mm","1",""
"J2","Conn_01x03","~","Connector_PinHeader_2.54mm:PinHeader_1x03_P2.54mm_Vertical_SMD_Pin1Left","1",""
"Q1","2N3904","https://www.onsemi.com/pub/Collateral/2N3903-D.PDF","Package_TO_SOT_THT:TO-92_Inline","1",""
"R1","1k","~","Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal","1",""
"R2","10k","~","Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal","1",""
"R3","3.3k","~","Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal","1",""
It looks like this:
errata: J1 is wrongly orientated.
That is my design and only works for a limited range of input voltages.
Exactly what are you trying to do?
A. In KiCad you can choose the drawing style with button K (Sketch Tracks) Show Tracks in outline mode - on left panel it is the cross of Red and Blue lines, striked diagonally - on left top are tracks full on right down are tracks outline. I strongly suggest using full tracks, if there is not reason for outlined (sometime outlined helps, usuall not)
B. These are dwo different tracks to Emitor and Base. Should be draw far away for clarity
C. Yes and probabely this is because they was originated on some other pad and should NOT connect to this pad, so Kicad did not allowed connection. This is visible that C area should be connected to Kathode of Diode (as diode is placed other way then on schema) The same happened for transistor, where it avoided bad pad connection (base should not go to diode Anode and Emitor should not go to Diode Kathode and Resistor joint)
The avoidance near Transistor is typical for KiCad avoiding bad connections. But user is unexperienced, so it looks this way.
Also it may have something to do with Router Shove Mode (Right click on icon Route Track (X))
Back when I switched from Eagle to KiCad (version 5 at that time), I found the e-book from here worth the price
Adding to the list of online resources, I consider this tutorial by Shawn Hymel (Digikey) excellent. The production quality is first class, it is well structured and very suitable for beginners. Here is episode 1:
You might want to take a look at Make Hobbyist PCBs With Professional CAD Tools by Modifying "Design Rules" : 15 Steps (with Pictures) - Instructables
Which I created many years ago. It's somewhat specific to EAGLE (as it was, back then), but many of the principles it sets forth would apply to any CAD package.