is there a software than converts schematic diagrams to IC layouts? where can I download it? thanks!

 

Here's a couple:
Cadsoft Eagle Layout Editor
http://www.cadsoftusa.com/
Express PCB
http://www.expresspcb.com/

 

Did you really mean IC layout? Or PCB layout?

For IC layout, there is no freely available automatic conversion software. Good IC layout softwares cost a lot of money.

There are free manual IC layout softwares if you are interested.

 

thanks for the links! I wanted an IC layout though... I'm having a hard time wandering through the manual IC layout softwares... I don't even know how to start! Do you have any free software on mind that's easy to use? how about a link for a tutorial? I really appreciate your help man...

 

Are you being trained in IC design? I hope you know fermi-levels and electron-band-diagrams well

Very typically, you are provided a library of standard components that work for a specific semiconductor fab. process. You must sign a non-disclosure agreement and pay a significant amount to them for the legal fees. If you are part of an academic institution, they will provide design rules / libraries for less advanced processes for free.

Nonetheless, you absolutely need design rules in order to start, whether you manually layout or use component libraries. The processes that they use are their intellectual property and they guard it well. The software that they use is very expensive, so good luck finding free software.

If you're worried about software costs, then have you looked into fabrication cost? Expect to spend at least 10000$ for the relatively old tech. fabrications... If you are able to go down to 90nM, then you're into some serious dollars! My school has a very special academic discount with a company for 130nM CMOS process, 300$ / mm^2. If you want the IC packaged (wire-bonded and molded), then add another 1000$ for a couple ICs.

The point is, you absolutely need to be part of an academic institution that is willing to pay for your graduate research or part of a major corporation that is planning a new ASIC.

Steve

 

Two of free ones that I've used are LASI and Magic. Both support MOSIS Scalable CMOS (SCMOS) technology file. SCMOS is somewhat less relevant now due to deep submicron processes. However, for educational purposes it is still widely used.

Both of them are easy to use, with tutorials available on the internet.

http://lasihomesite.com/
http://opencircuitdesign.com/magic/

 

I know one named "Electric".

 

Two of free ones that I've used are LASI and Magic. Both support MOSIS Scalable CMOS (SCMOS) technology file. SCMOS is somewhat less relevant now due to deep submicron processes. However, for educational purposes it is still widely used.

Both of them are easy to use, with tutorials available on the internet.

http://lasihomesite.com/
http://opencircuitdesign.com/magic/

tried lasi and went bongo ... I'm having a hard time learning how to use this software... any tips??

 

I know one named "Electric".

can you give me more info about this software?

 

umm...pardon my stupidity... but can multisim or proteus do this?

 

can you give me more info about this software?

http://www.staticfreesoft.com

(* jcl *)

 

I've used Electric also, very tedious and buggy

Steve

 

umm...pardon my stupidity... but can multisim or proteus do this?

The whole point of entering in the design is to extract the spice netlist. So, you'd have a schematic that you wish to implement, you place each transistor (collector, base, emitter) with the appropriate w/l ratio. You interconnect it all, then you can generate SPICE that you can simulate.

Steve

 

tried lasi and went bongo ... I'm having a hard time learning how to use this software... any tips??

I'm sorry to hear that. LASI, which I like better than Magic, is about as simple as it gets. There are commercial packages that are way more difficult than LASI. The only tip that I have is to go through the documentations and then the tutorials. There is no shortcut, you just have to steel yourself and do it.

I take it that you are working on digital design, because you referred to logic gates? If so, it would be simpler to tackle this in steps, such as creating standard cells first, before laying out the circuit. It depends a lot on the size and complexity of your design. Small and straight forward design would not benefit so much from having standard cells.