# A nand gate becomes ___ gate when used with negative logic ?

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#### SathyaGopi

• Jun 1st, 2005

NAND gate becomes AND gate when used with negative logic.

NAND gate turth table(with -ve logic)
0 0 0
0 1 0
1 0 0
1 1 1 -> this is truth table of AND gate

#### poornima.V

• Aug 25th, 2005

C this website. Ans is Nor gate. that is convert one tozeroes and vice versa.

http://www2.ele.ufes.br/~ailson/digital2/cld/chapter2/Ex02.doc.html

#### Neha Sinha

• Oct 31st, 2005

It becomes an and gate

#### ankit garg

• Jan 6th, 2006

my lord.it becomes a AND Gate ....such a simple question.

#### Anjum

• Mar 21st, 2006

When used with negative logic means that the inputs are inverted.

If the inputs of a nand gate are inverted and given, the output will be an OR of the inputs. De morgans law (A'.B')' = A + B

#### geek

• Apr 18th, 2006

OR gate is the right answer

• May 30th, 2006

ANS is nor gate

negative logic means a high is interpreted as low and vice-versa

poornima is right

#### sateesh

• Jun 11th, 2006

it is so simple it becomes an AND gate when we use negative logic becuase NAND means that Negaive AND

#### sudhanshu

• Jul 10th, 2006

The NAND gate becomes a "OR" gate because
(a'.b')' = ((a+b)')' = a+b (by De-Morgan's)

#### bhartimasand Profile Answers by bhartimasand

• Jul 13th, 2006

Nor gate

#### pearlin

• Jul 28th, 2006

it is NOR ofcourse

#### djdansays Profile Answers by djdansays

• Aug 7th, 2006

it is NOR gate. Lets analyse how.

In positive logic 0s are considered low and 1s as high voltages. In negative logic 0s are high and 1s are low. Now the truth table for Nand is

A B Y         A(V) B(V) Y(V)-> positive logic

0 0 1         low    low   high

0 1 1         low   high   high

1 0 1         high   low   high

1 1 0         high   high  low

Now when used as negative logic then the truth table will be

A B Y

1 1 0

1 0 0

0 1 0

0 0 1

hence it is NOR gate.

#### abhilash

• Sep 12th, 2006

an and gate with negative logic becomes nor gatetruth table for and gate is0 0 - 01 0 00 1 01 1 1we get 1 1 1 0 it is for nor gate

#### Anitha

• Oct 13th, 2006

OR gate

#### anithaarulraj Profile Answers by anithaarulraj

• Oct 13th, 2006

OR gate

#### anithaarulraj Profile Answers by anithaarulraj

• Oct 13th, 2006

OR gate

#### hardik parikh

• Oct 27th, 2006

hi , it will become AND gate at there.

#### Ben

• Nov 1st, 2006

First of all, a NAND gate is not (a'.b'), it is (a.b)' -- that is, (a'+b'). When you negate this, you get (a'+b')' which you can then de-morgan to get (a.b). So a NAND gate become AND

#### nagalakshmi

• Dec 4th, 2006

it becomes 'OR' gate..so simple apply Demorgan's laws..u will get 'OR'.

#### shirish

• Jul 23rd, 2007

The ans is OR GATE.

#### sexopedia Profile Answers by sexopedia

• Dec 1st, 2007

ediots go to page no 64 fig 2.11 NAND with negative logic is nor

#### prabhakar5555 Profile Answers by prabhakar5555

• Feb 26th, 2008

ya sudhansu has explained it correctly...
actually from de-morgan's
(a'b')'=((a+b)')=(a+b)

#### sanjaypandey170 Profile Answers by sanjaypandey170

• Jun 30th, 2008

he dude it will b or gate so simple logic----
(a'b')'=a''+b''=a+b

#### bexdeep Profile Answers by bexdeep

• Aug 17th, 2008

Yes i think it becomes nor gate because using a negative logic doesn't mean doing any mathematically. it means just suposing zero to be one and viceversa

#### Survinderpal Profile Answers by Survinderpal Questions by Survinderpal

• Mar 8th, 2009

OR GATENAND gate in negative logic (convert 1s to 0s & vice versa of positive logic)
1 1 1
1 0 1
0 1 1
0 0 0
This is truth table of OR gate

#### gvikashnaidu Profile Answers by gvikashnaidu

• Sep 8th, 2009

It becomes a NOR gate

L L H
L H H
H L H
H H L

Now assume
H=1 and L=0 we get NAND
H=0 and L=1 we get NOR

Similarly for AND gate we get OR gate

#### hellslayer Profile Answers by hellslayer

• Nov 10th, 2009

NAND gate with negative logic becomes a NOR gate with positive logic.

#### seemak Profile Answers by seemak

• Apr 9th, 2010

It is OR gate.

#### SUBASH

• Sep 11th, 2012

NOR gate

#### MANISH MANCHANDA

• Jun 16th, 2016

NOR gate

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