Electronics-Lab.com Community

LOGIC GATES project

Recommended Posts

hi! a friend asked  for help regarding his project involving logic gates..

its a simple illustration o about how logic gates function.. is it possible to integrate all the kinds of logic gates into one circuit? for example, the output of a NOT gate will be one of the inputs of am AND gate while the other input is the output of a NOR gate.. is that possible? what should i use? i prefer IC than transistors..

Can you please show me how.. tahnks a lot..

• Replies 53
• Created

Popular Days

Hi Logan

Do you mean like this?

//Staigen

Share on other sites

GREAT! but what is that? is that an IC? what IC?
Share on other sites

Hi Logan

Its logic gates, dont bother about pin-numbers, i forgot to erase them!
Just see them as logic gates. In reality its 3 IC:s, but they have more
logic gates, the IC containing the NOT gate(usally called inverter) have
6 gates in the same IC, and the other 2 have 4 gates in each IC. You
can use CMOS or TTL, it dosent matter, you can't mix them thou, well,
sometimes you can do that too. Get yourself a pair of good books about
TTL and CMOS, and you will soon learn how it works. The picture is
showing what you requested.

//Staigen

Share on other sites

Audioguru and I had a discussion about logic gates last night on MSN. You were "away" so i didn't bother PM-ing you.. I understand that they are 3 IC's..

just a question.. an IC can contain up to six gates, then why is it not possible to have different gates in a single IC? or is it? I've been looking at datasheets and i think haven't seen an IC that have multiple gates in them..

Share on other sites

Hi Logan

Look at CD4000, it have two 3-input NOR gates and one NOT(inverter)
But it is unusual, i admit that.

//Staigen

Share on other sites

WAAaaaa!!!

just a question.. an IC can contain up to six gates, then why is it not possible to have different gates in a single IC? or is it? I've been looking at datasheets and i think haven't seen an IC that have multiple gates in them..

It is possible!! It's just now that i found one.. can i use this?

Hi Logan

Sure, why not?

//Staigen

Share on other sites

Is there an IC that has AND and OR instead of NAND and NOR just like in a 4572? Can you please help me find one.. I always end up with 4572.. I prefer using an AND and a NOT.. tahnks...
Share on other sites

Hi

For an OR: Connect pin 4 and 5, output at pin 3
For an AND: Connect pin 12 and 13, output at pin 11
Also think of that every input MUST be connected to
something that have a logic state!

//Staigen

Share on other sites

DUH!?! could i be dumber that Dumb&Dumber?! Of course, what are the inverters for?!

thanks Staigen! I hope the IC is available in the stores..
Share on other sites

Just as i predicted! It's not available.. what now? anybody knows a replacement..

i have searched datasheets and i came up with..
SN7451
CD4019B
5400
7400

there's also the AND-OR-INVERT gates in HD74 and HD74S series..

Share on other sites

an IC can contain up to six gates, then why is it not possible to have different gates in a single IC? or is it? I've been looking at datasheets and i think haven't seen an IC that have multiple gates in them..

If you just think of it as digital logic than you could use a programmable logic device.  Like a GAL chip or a FPGA where you don't worry about the gates so to speak but just come up with the logic expression using truth table, K-map, or whatever method you prefer.  I think in this case this is not what you want I just thought I would mention it though.  I think some FPGA's have a million gates...not sure, but I know the ones we used had tens of thousands of gates.  Neat stuff.  I also seem to remember being told that NAND gates are cheaper than AND so people would adjust their logic to use NAND gates for production projects to save money.  I also figure that whatever logic configuration is the most popular is what will be produced.  Sorry just rambling.
Share on other sites

hi wvengineer! thanks for the additional info..

i think i'll just use TWO IC's for the project..
Share on other sites

In order to demonstrate the logic functionality that you describe you actually don't need to use any logic gates at all.

I have emailed you an idea that uses 3 switches, one resistor, one LED and a 9 volt battery.

Share on other sites

i received an email at my Yahoo from a new member of the eLab.. it was hs idea on how

Share on other sites

Hi dave!

thanks a lot for your idea but it is really important that the circuit contains real gates..

the next time, attach files in jpg, or png format.. if your attachment is in bmp format, simply use "save as..." in the file menu and below the file name, you'll see a dropdown menu what format you want it to be saved. choose JPEG..

tahnks again for the idea..
Share on other sites

Hey Logan

You can also use one of the 3-input NOR gates of the CD4000 IC,
reducing the amount of IC:s to just only one, dont forget to connect
the other gate:s inputs to something that have a logical state! But
i belive the project is a scool project that needs to have all the
gates. But a little text about it can be good to present to the
teacher, so he see that you have penetrated the question properly!

[move] :) ;) :D ;D >:( :( :o 8) ??? ::) :P :-[ :-X :-\ :-* :'( :) ;) :D ;D >:( :( :o 8) ??? ::) :P :-[ :-X :-\ :-* :'([/move]

//Staigen

:)

:)

Share on other sites

thanks.. i have already asked my friend to purchase a CD4071 (quad 2-input OR gate) and a CD4081 (quad 2-input AND gate) he'll be at my place tomorrow.. i am planning to have it assembled in an illustration board.. i have a schematic circuit drawn in the board, drill holes for the LEDs and the IC's and at the other side, have the wires.. what is better to use, a switch or an alligator clip? he said that the power supply would be that from an AC/Dc converter.. probably 12V, right?
Share on other sites

:)you may like my logic ic tester in the forums somewhere to

Share on other sites

http://www.electronics-lab.com/forum/index.php?topic=627.0

Nice Project! is that limited for a 4011 only and some other 14-pin ICs? how about those with 16 pins? i noticed the stickers pasted on its chassis.. "4011, 4093 and 4001" are those the only ICs that can be tested by that project? anyway, i don't plan to build one, i'm just curious..

Share on other sites

:)the logic ic tester tested all those that are listed , and it was my prototype to and was really handy but now that ive upgraded it to a printed circuit version its not testing the 4001 and i think it may be because my 4001 ics are faulty i think they may be static sensitive and got damaged by it im not really sure , so ill get some new ones and try again as this teaster allways tested them ok before

Share on other sites

i thought i got the whole thing figured out!  ??? where would i put the LED? the supply? i am using a 4071 (OR) a 4081 (AND) and a 4069 (inverter).. the output X is = AB + B'

i have the inverter connected to input 2 of AND. outputs of AND and inverter are the inputs for the OR..

i got confused.. ??? i suspected that the breadboard im using is defective but i think there is something wrong with my wiring..

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.