You are here

XOR Gates | Cypress Semiconductor

XOR Gates

I have a question about XOR gates.  XOR is short for exclusive OR and gives an output when a single input is high.  The output is high when the number of high inputs is odd.  It can also by thought as a parity generator.  A two input is the only case that exclusive and parity are equivalent,

 

A | B |Out

--+---+---

0 | 0 | 0

0 | 1 |.1

1 | 0 | 1

1 | 1 | 0

 

Here is the problem.  With more than two inputs the output should only be high when a single input is high. An example is shown below:

 

A | B | C |Out

--+---+---+---

0 | 0 | 0 | 0

0 | 0 | 1 | 1

0 | 1 | 0 | 1

0 | 1 | 1 | 0

1 | 0 | 0 | 1

1 | 0 | 1 | 0

1 | 1 | 0 | 0

1 | 1 | 1 | 0

 

 

The output is high only when a single input is high. (Exclusive)

 

 

On one of our new logic components a three input XOR is defined as.

 

 

A | B | C |Out

--+---+---+---

0 | 0 | 0 | 0

0 | 0 | 1 | 1

0 | 1 | 0 | 1

0 | 1 | 1 | 0

1 | 0 | 0 | 1

1 | 0 | 1 | 0

1 | 1 | 0 | 0

1 | 1 | 1 | 1

 

The output is high only when the number of high inputs is odd.  This is technically not an XOR gate.  It is a parity generator.

Am I correct?  Or did someone decide that XOR means parity?  If so why not just call it “parity”?

Sent!

 

 

 

 

 

 

 

ALL CONTENT AND MATERIALS ON THIS SITE ARE PROVIDED "AS IS". CYPRESS SEMICONDUCTOR AND ITS RESPECTIVE SUPPLIERS MAKE NO REPRESENTATIONS ABOUT THE SUITABILITY OF THESE MATERIALS FOR ANY PURPOSE AND DISCLAIM ALL WARRANTIES AND CONDITIONS WITH REGARD TO THESE MATERIALS, INCLUDING BUT NOT LIMITED TO, ALL IMPLIED WARRANTIES AND CONDITIONS OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT OF ANY THIRD PARTY INTELLECTUAL PROPERTY RIGHT. NO LICENSE, EITHER EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, IS GRANTED BY CYPRESS SEMICONDUCTOR. USE OF THE INFORMATION ON THIS SITE MAY REQUIRE A LICENSE FROM A THIRD PARTY, OR A LICENSE FROM CYPRESS SEMICONDUCTOR.

Content on this site may contain or be subject to specific guidelines or limitations on use. All postings and use of the content on this site are subject to the Terms and Conditions of the site; third parties using this content agree to abide by any limitations or guidelines and to comply with the Terms and Conditions of this site. Cypress Semiconductor and its suppliers reserve the right to make corrections, deletions, modifications, enhancements, improvements and other changes to the content and materials, its products, programs and services at any time or to move or discontinue any content, products, programs, or services without notice.