On Mon, 14 Dec 2009 13:25:21 +0000, you wrote:
>Thanks for the responses. My reasons for asking are a mix really. I am
>an engineer by trade but also I am just really being curious. I do not
>have a specific need for a 4 layer board right now. I have laid out 4
>layer boards in the past though and for some reason always fancied
>making them myself. I have never tried yet.
>
>I like to make things smaller and smaller so 4 layer boards enable that.
>For one company I worked at a few years ago I did the cad work for a
>board that was 12mm x 10mm and needed to be 4 layers because of all the
>tracks.
>
>Last year I quite fancied making a board based on the AVR32 and this
>looked like it would have to be 4 layers at least. Getting a couple of
>prototypes made would cost both time and money and well I did not have a
>real need for the board. I just wanted to make one. So that project got
>shelved.
I have a board design with a MEGA2560 and an epson graphics driver
chip, a 512K∗8 RAM and assorted other parts. Does well on a double
sided board. 4 layer would be nicer, but not needed by the design. A
bit of careful layout has produced only one jumper on the board.
Harvey
>
>So I think I would probably use the skills in my work occassionally but
>i am not sure if I was truely doing it for professional reasons it would
>make financial sense. I certainly do not have cash to invest to prove
>that. I think I just want to make more and more complex, small boards.
>
>Trev
>
>
>
>
>
>
>Andrew Mathison wrote:
>>
>> Dear Trevor White
>>
>> with regards to your question about 4 layer boards (which are easily 4
>> times more expensive to have made,in my experience, than double sided
>> ones....), are you a hobbyist or professional? Because if you are a
>> professional, the price (almost !) does/should not matter.....
>>
>> If you are Hobbyist, then you should give some thought to redesigning
>> the board for double layer, even if its a bit bigger because of
>> that.... Fault finding on 4 layer PCBs is not for the faint hearted
>> either and repairs can be a nightmare.....
>>
>> If you are developing something privately, for maybe later selling,
>> may I still suggest that until the design is working perfectly, that
>> you stay with double layer, get some experience with that and when you
>> really go for "IT", do the 4 layer design. You may get some new
>> problems but YOU WILL KNOW EXACTLY WHY!!! Which is like money in the
>> bank!!!
>>
>> I would be most interested in learning why (if) you feel that a 4
>> layer is the only way to go in your particular case......
>>
>> (I have to admit that my personal (not business I hasten to add, we
>> used multilayer pcbs all the time there) PCB level is far less
>> complicated than yours, I design using my PCB software at first double
>> sided (my old software makes a mess/gives up when telling it to design
>> single sided!) and then try and redesign by hand to fit a single sided
>> PCB - it appears that I like wire links a lot!!! Or better said, they
>> do not bother me at all......I can usually manage to get probably 90%
>> of my designs (thats probably between 4 and 8 boards a year!!) onto
>> single sided - not that I am anticipating you changing a 4 level
>> design to ever fit single sided PCB, that was NOT my meaning!! Double
>> at least I would still guess.....)
>>
>> Stay well and regards from
>>
>> Andy
>>
>> [Non-text portions of this message have been removed]
>>
>>
>
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