Hi
i m actually new in pcb designing, i have downloaded few softwares like FREEPCB, NI Ultiboard, eagle.
but all of them are little tough to use, like using multisim i can easily place a IC, but here the scenario is different, i just cant understand which footprint is of my IC, and none of them matches mine (74160), i have taken some printout of sample design but they are too small, even my 1 single ic is bigger than the prinout.

So please help me getting started

 

To be specific about your logic IC, the 74160 comes in a 16 pin DIP package. To do the layout, you place a 16DIP (or whatever the name might be) pattern wherever you like, and make connections following the pinout from the IC's data sheet.

The package any device comes in is standard. The pins used for the various functions may be different for each device.

 

and whatt about 7 Segment Digital Display, Which package does it uses ?

 

For chips that are basic unknowns to the software they usually still use a standard pattern, such as the 16 pin DIP. You can link individual pins to networks as I understand it.

You can usually find a pattern in the library. If not, it is possible to draw patterns yourself, but this is beyond the scope of what I know.

 

The best approach is to obtain the data sheet for each and every device. With that in hand, you have the exact footprint for the PCB and the function of each pin.

 

I know the function of each pin, but i cannot find the footprint of these display's

 

Do you have the data sheet for the display? The footprint should be there. Otherwise, since you know the pinout, just grab a ruler and measure away. Learning to make your own footprints is an important part of learning to design PCBs.
/mike

 

i google the datasheet of 7 segment digital display, but couldnt find any..

 

There are many 7 segment (often + a decimal) parts out there but the pinouts isn't necessarily going to be the same on every one.

You need the data sheet pertaining to the one you're using.