9 votes 9 votes What is the minimum number of two-input $\text{NAND}$ gates used to perform the function of two-input $\text{OR}$ gate? One Two Three Four Digital Logic isro2017 digital-logic min-no-gates + – Arjun asked May 9, 2017 • edited Jun 9, 2020 by Sabiha banu Arjun 9.1k views answer comment Share Follow See 1 comment See all 1 1 comment reply papesh commented May 10, 2017 reply Follow Share It is direct question. Ans =3 0 votes 0 votes Please log in or register to add a comment.
Best answer 14 votes 14 votes Need only 3 NAND Gate : A+B = ((A + B)')' = ( A' .B' )' Prashant. answered May 10, 2017 • selected May 10, 2017 by ManojK Prashant. comment Share Follow See all 4 Comments See all 4 4 Comments reply Aditya Vikram Sinha commented May 12, 2017 reply Follow Share I think answer is 1. Since it is asked minimum number of NAND GATE and also it is not mentioned that we should use only the NAND GATEs.......so we can use 1 NAND GATE and two NOT GATEs...but if maximum numbers of NAND GATEs would have been asked...then the answer would have been 3. 0 votes 0 votes Prashant. commented May 12, 2017 reply Follow Share Question doesn't say that we can use another gate except Nand gate. 0 votes 0 votes Aditya Vikram Sinha commented May 13, 2017 reply Follow Share In th question it is just asked minimum no. of NAND Gates....It is not said that we are bound to use only NAND gates. 0 votes 0 votes Prashant. commented May 13, 2017 reply Follow Share ok thankyou :) 0 votes 0 votes Please log in or register to add a comment.
5 votes 5 votes by using NAND by using NOR NOT 1 1 OR 3 2 AND 2 3 NAND - 4 NOR 4 - EX-OR 4 5 EX-NOR 5 4 so by using 3 NAND gate we can perform OR gate operation pawan kumarln answered May 10, 2017 • edited May 10, 2017 by pawan kumarln pawan kumarln comment Share Follow See 1 comment See all 1 1 comment reply Sahil1994 commented Dec 8, 2017 reply Follow Share @pawan KumarIn Sir, if we have gates with different fan-in and fan-out. will this table be same....? This table is standard for 2 fan-in and 2 fan-out...? 0 votes 0 votes Please log in or register to add a comment.
3 votes 3 votes Gate Min NAND MIn NOR AND 2 3 OR 3 2 NAND 1 4 NOR 4 1 EX-OR 4 5 EX-NOR 5 4 For NOT gate only 1 NAND & NOR gate are enough to realize. & IF from 2 Input NAND gate we want to realize n-input NAND gate then it will be 2n-3. POOJAN SHAH answered Aug 24, 2017 POOJAN SHAH comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes 3 nand gates for or and 2 for and. Purvi Agrawal answered May 10, 2017 Purvi Agrawal comment Share Follow See all 0 reply Please log in or register to add a comment.