Connect the two inputs of the NAND gate together.
by the procedure design a half subtractor design a logic ciruit to add two numbers with five bits each drawthe logic diagram of afull adder using using NAND gates only ?
You cannot design a full adder using only OR gates. You also need AND gates. Typically, this can be done with just NAND gates.
Its possible to design a 4-i/p xor gate using only 2-i/p nand gates Although the design turns out to be quite complex and comprises of 21 NAND gates : F = (A'B+AB')(C'D'+CD) + (A'B'+AB)(C'D+CD') Above given equation is the o/p equation for the circuit .
That title of "Universal Gate" is reserved for NAND gates because you can build all possible logic using only NAND logic . You can build even other basic logic like AND, OR and NOT using NAND.
That title of "Universal Gate" is reserved for NAND gates because you can build all possible logic using only NAND logic . You can build even other basic logic like AND, OR and NOT using NAND.
Next: Boolean Expressions Up: Universality of certain gates Previous: Universality of certain gates ContentsUsing NAND gatesNOTFigure 12.10: Realizing a NOT gate using a NAND gateOR The following statements are called DeMorgan's Theorems and can be easily verified and extended for more than two variables.(12.1)(12.2)(12.3)(12.4)In general: (12.5)Thus :(12.6)Now it is easy to see that , which can be checked from the truth table easily. The resulting realization of OR gate is shown in 12.11Figure 12.11: Realization of OR gate by NAND gatesAND gateFigure 12.12: Realization of AND gate by NAND gatesX-OR gate(12.7)Clearly, this can be implemented using AND, NOT and OR gates, and hence can be implemented using universal gates.Figure 12.13: X-OR gateX-NOR gate(12.8)Again, this can be implemented using AND, NOT and OR gates, and hence can be implemented using universal gates, i.e., NAND or NOR gates.Figure 12.14: X-NOR gateNext: Boolean Expressions Up: Universality of certain gates Previous: Universality of certain gates Contentsynsingh 2007-07-25
There is no such thing as an R-S NAND gate.The datasheet for a 7474 IC will give you a schematic for a D flipflop using NAND gates only.
As this is obviously a homework problem, I won't answer it. However I will give you couple of hints. First figure out how to make an exclusive-or gate from nand gates. The rest is trivial. Using a Karnaugh map will make it much simpler to design than using an ordinary truth table.
Yes, but only if its output is logically inverted (a AND gate's behavior is a direct opposite of a NAND gate's behavior, logically).
No. OR is not functionally complete, so you can not use it to derive any other logical expression. The reason for this is because you can only construct the following expressions out of only OR gates: A OR B A OR A Because of the Idempotency theorem, A OR A simply reduces to A, so we are left with A OR B, which we can not use to derive any other logical circuits. At the very least, we would also need a NOT gate. This is why NOR and NAND are functionally complete: you can derive a NOT gate by using A NAND A or A NOR A.
No. OR is not functionally complete, so you can not use it to derive any other logical expression. The reason for this is because you can only construct the following expressions out of only OR gates: A OR B A OR A Because of the Idempotency theorem, A OR A simply reduces to A, so we are left with A OR B, which we can not use to derive any other logical circuits. At the very least, we would also need a NOT gate. This is why NOR and NAND are functionally complete: you can derive a NOT gate by using A NAND A or A NOR A.
A universal gate is a logic gate that can be used to implement any logic function. The NAND gate and NOR gate are examples of universal gates because any other logic gate can be constructed using only NAND or only NOR gates.