Circuit Simulator that has a wide range of 7400-series integrated series

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Shinjid

Joined Mar 22, 2020
1
Hi! I need to design the schematic diagram of an 8 x 8-bit multiplier in a circuit simulator for one of my subjects. I searched for the schematic and now a 4 x 4-bit multiplier IC which is SN74x274. I tried using multisim but they don't have that IC, is there any other circuit simulator that has this kind of IC?
 

Alec_t

Joined Sep 17, 2013
10,918
Welcome to AAC!
Try LTspice (freeware from Analog Devices). Many members here use it and it can accept third-party models. Member @Bordodynov probably has a suitable model in his extensive collection.
 

ci139

Joined Jul 11, 2016
1,195
? what level . . . if it's a logic level - all you need is the pencil and the paper ← the benefits are . . . you do not need software specifics to get (started) it done
 
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377Ohms

Joined Sep 9, 2015
9
@Shinjid...

I have the 74HC library for LTspice. My version is a bit dated and does not have the 74HC274 4-bit by 4-bit binary multiplier, or any binary multiplier for that matter. However it does have the 74HC283 4-bit binary full adder with carry IC, that will probably help you to build the multiplier. See this page for some tips:

https://www.electricaltechnology.org/2018/05/binary-multiplier-types-binary-multiplication-calculator.html

But if memory serves, I think you can build any NxN binary multiplier out of just combinational logic gates (especially with the XOR gate). For example, this Wikipedia page has a schematic of a 2x2 binary multiplier that uses six 2-input AND gates and two 2-input XOR gates:

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

Perhaps you can extend that 2x2 bit example, or search for other examples on the Web. In any case, at some point you will find a solution that will run in LTspice with the 74HC library installed. Actually, if your schematic is limited to just combinational gates (including the XOR), you don't even need the 74HC library in LTspice because LTspice already has behavioral models for the basic combinational logic gates built in!

Here is where you get LTspice, it is free to download and you don't even have to enter your Email address. LTspice is not crippled in any way. LTspice runs natively in Windows and Mac OS 10. In Linux LTspice works OK under Wine:

https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice-simulator.html

Note: Linear Technologies Incorporated (LT) was the original creator of LTspice, but LT was bought-out by Analog Devices Incorporated (ADI), so ADI has taken over the development and maintenance of LTspice. In my opinion LT was a great company that really cared about their customers, not so much ADI though. But to be fair, ADI has kept LTspice alive and free - for now.

You will need some help getting started with LTspice plus you will probably want to download and install the 74HC library. For this you will need to join the LTspice group:

https://groups.io/g/LTspice

In the LTspice group explain that you are new in LTspice and what you want to do with the 74HC library (if you need it). Also ask where the file area is for both the 74HC library and the list of LTspice tutorials. Also search on YouTube for LTspice tutorials. In my opinion spending the time to learn LTspice is a good investment.

Good Luck - David in Florida
 
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