You can use Electric VLSI Design System. The download files and tutorials are available in this link:

http://cmosedu.com/cmos1/electric/electric.htm

There is another software called Magic. You can try that as well.

Dear Mubarak,

Please follow the given link to be informed about the open source mixed circuit design. You can use winspice as low cost circuit simulator and use LASI as lay out tool. You need a technology file to make a successful design. and you can use the so called universal lambda based lay lout rules. With these tools we could design and simulate analog and mixed ic circuits: http://www.edaboard.com/thread174733.html

best wishes

hspice .. is available for windows and linux platform

You can also download student version of Cadence OrCAd simulator.

You can use Electric VLSI Design System. The download files and tutorials are available in this link:

http://cmosedu.com/cmos1/electric/electric.htm

There is another software called Magic. You can try that as well.

The well known EDA simulation tools based on Spice are

from Cadence (Spectre), Mentor (Eldo), Synopsys. All of them have also the complete flow from Schematic down to Mask Layout and their verification (Checks like DRC, ERC, LVS and parasitic extraction for postlayout simulation!).

There is a little less expensive solution from Tanner/Mentor (TSpice) including the whole flow from Schematic Entry to Sim, to Layout & Layout Verification.

But there is a lot of academic, thus freeware EDA tools!

Frrom Spain:

http://www.cnm.es/~pserra/apdk/

and their Spice Opus:

http://fides.fe.uni-lj.si/spice/

or X-Circuit http://opencircuitdesign.com/xcircuit/

NG Spice for Lnx & Win:

http://ngspice.sourceforge.net/download.html

Start reading also Wikipedia pages, there is a lot of introduction to the topic:

https://en.wikipedia.org/wiki/Comparison_of_EDA_software

________________________________________________________

Here is a good overview of free EDA tools for transistor mask layout:

https://mixedsignal.wordpress.com/2011/01/29/top-ten-full-custom-layout-tools/

http://www.vlsitechnology.org/html/ic_software.html

_____________________________________________________________

This should help you as an introduction

Best regards

Richard

Cadence is the one of best stimulator for IC Design

Dear Mubarak,

It is well-known that, you can use the SPICE ( HSPICE) model of the simulator for simulating of the your design, simply. Also, for drawing Layout of the your structure you can use the Cadence software.

Meanwhile, if you want to simulate your design just behavioral model, in that time the Simsides model simulator is good candidate for simulating, because in the mentioned simulator model, you can apply the effect of the parasitic resistors and capacitors, the effect of the noise and temperatures, and other parasitic parameters too, generally. Due to that these type simulation results are near to actual way, mostly.

All the above are really good suggestions. Another open source simulator that you could use is also QUCS (Quite Universal Circuit Simulator).

http://qucs.sourceforge.net/

can anyone share the link for downloading Hspice software...

Well the best one so far I found is LTSpice.

TINA -TI is good one

I currently use LTSpace. It is an excellent simulator and is compatible with other software.

You could try vspice3 (as it's free).

www.designsim.com.au/dssdnld.html