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Questions relating to designing PCBs
By bart796
#174438
I have this Schematic Image
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I designed this PCB to go with that circuit (I have the circuit working on a breadboard with so i know it works) Some of the components are not exactly the same as what i used because the program didnt have them so the resistors are not surface mount and that thing labeled mosfet is not a mosfet in the program but it was close enough for me to use as a standin. Image
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By InactiveUser001
#174487
ISTR that you would put a resistor in the top/bottom ends of the pot so that you do not swing all the way up\down.

Have another look at your tracking, especially the gnd\0v track.

it comes in nice & thick then goes thin to the rest of the circuit esp the mosfet - yet you have enough room for it to be as thick.

move r6/r7 closer to the pins of U1, rotate PL1 clockwise 90 and move to the end of the resistors.

rearrange the other resistors to try and get the distance between the pins of the ic and the resistors short and C1 directly on the pin of the IC (which it currently is not connected to?).
By bart796
#174496
Hmm yea the schematic was easy to follow on a bread board. All i did was each individual blue square was a separate row on the breadboard. Because of this i am having difficulty translating it into a PCB. C1 in the schematic and on my breadboard does not directly connect to the IC (i assume IC is the lm339?). On my breadboard every blue square has a line so for instance R3 R4 R5 all have 1 pin sharing a row on my breadboard and none connects directly to the ic etc. This is why im having trouble converting it to a circuit.
By InactiveUser001
#174569
If your having trouble it may be best to scrap it and start again and use Eagle.
ISTR that PCB artist locks you to advanced circuits where eagle allows you to output gerber files that anyone can use.

With Eagle you should be able to draw the schematic and then transfer the schematic to a PCB with a pile of components joined together by connections that you can then make into tracks.
See https://learn.sparkfun.com/tutorials/us ... ard-layout

This then gives you a huge net base of Eagle users who can help, sparkfun libraries etc.
(Unfortunately I do no use eagle myself).

But the important thing is getting the PCb circuit to match the schematic one, otherwise it may not work etc.

Then you can see about how to layout the PCB.