Flip Flops and clocks with multisim

1. Nov 18, 2005

ranger

Hey all,

I'm trying to build a circuit using flip flops that passes data in series using multisim. My problem is with the clock. I know that data isnt moved until a clock pluse comes along. My problem is that what exactly is the source of this (clock) pulse. Could it be a voltage source and a switch, opening and closing the switch causes the square wave? If not, how do I put a clock in multisim and in a real circuit?

I ask this because the schematics I've been looking at only shows the clock as square waves or coming straight from something that says "clock".

--thank you

Last edited: Nov 18, 2005
2. Nov 18, 2005

Staff: Mentor

I'm not familiar with MultiSim, but in MicroCAP and most other SPICE based packages, you would put down a Voltage Source, and set its parameters for the clock frequency and voltage levels. Does that work for you?

3. Nov 18, 2005

ranger

Umm...now that you mention frequency (which I had completely ignored before), I did some more searches in multisim's component database. I think I may have found something. It looks like a AC source but instead of the sine wave, it has square waves. And it also has settings for frequency and voltage. I think that may be it.

But I wiring it up, do I put one end of it to ground and the other running to CLK of the flip flops?

thanks again.

4. Nov 18, 2005

Staff: Mentor

Yep, you've got the right idea.

5. Dec 8, 2005

ranger

I found this

http://csserver.evansville.edu/~blandfor/WrkBnchTutorial.pdf

Multisim uses the function generator to generate the square waves. I tried the "clock source" that I discussed above and that did not work. The function gen does the trick though.

6. Dec 9, 2005

mfk_1868

yes you need to use function generator for clock usage. I got digital circuit design course in university and we used fnc generator in labs for CLK.

7. May 6, 2011

nahidxy

Go to "Place>component>sources>digital_sources>digital_clock" from your multisim. i found it in my multisim11.... i think you got your specific answer... :)