Hello everyone. I am trying to make a light bar for my monitor since the foresent tubes in the monitor decided to die on me. So I have created a sketch on Ki Cad and I am trying to figure out if i have done this right. What i want is basically a piece of copper or anything with a straight line connected to ground and a straight line connected to VCC with a gap in between so it doesnt short. so it would look like this =[]=[]=[]=[]=[]=[]=[]=[]= with each [] being an LED and each = being a piece of copper with like 2 nodes/ pads on the ends so I can connect VCC and GND to. I am just wondering what way is better to do this as this seems to be very difficult. oh also it needs to be 18inches long and no wider then like 5 mm yep small area heres a picture of what KiCad is doing.
as you can see I am not sure if i should have via’s in the pads area as i dont know if it will work that way or not. but its also complaining that the one trace is to close to a pad but I am not sure how to fix that as it wont let me put the trace on the back side connected to the pads on the top side… so I really dont know whats going on here… If anyone can explain this it would help a lot please thank you
From your description, it sounds like you are trying to paint your PCB without a net-list. I would recommend that you model the schematic of the light bar first and then create your PCB from the schematic. This way will have a net-list that the PCBNew can work with. You will then find that the LEDs will connect to the tracks.
This is not a good way to design a LED strip unless your LED has a resistor or current regulator incorporated in it. There are plenty of articles out there that explains about the problems of directly paralleled LEDs, so I won’t rehash them here.
When you place your traces, are you wiring from a pad with a net assignment? If no, you might be wiring a “no net” condition alongside tracks with a net, which is a violation.
As for the specific board you posted, look at the DRC error report to see what the exact errors are. What is that footprint that overlaps the D68 designator? Is that supposed to be a pair of wire holes or a connector or something else?
The resistor will be going closer to the in line power considering the fact the area that i am able to put this into is like 7mm wide and 18 inches long i have to make it like this then line a way to get to the power lines. basicly its an attempt to turn an tube back light to an led back light.
Those holes would be vias i was trying to get it so theres lines on bottom and top i dont know if thats right or not…
Sounds like you aren’t going into mass production. Maybe this company has either a LED of CCFL
solution that meets your needs. https://www.ccflwarehouse.com/index.html
Vias are not electrically necessary for a simple circuit like this, but if the LEDs need heatsinking it is helpful to have multiple vias in the pads to allow good heat transfer to the back of the strip.
Also - unless you are okay with less-than-ideal reliability and operating life, you ought to use one resistor per LED unless the LEDs are extremely well matched (within 10%) for current vs voltage. The LEDs should also be matched for luminous intensity vs current if you want the LEDs to be uniformly bright.
Finally, you can adjust the DRC parameters to avoid the spacing errors you’re getting; just be sure the fabrication process can meet the new parameters.
yep small area heres a picture of what KiCad is doing.
