Question

How is an encoder different from a decoder?

(a) The output of an encoder is a binary code for 1-of-N input

(b) The output of a decoder is a binary code for 1-of-N input

(c) The output of an encoder is a binary code for N-of-1 output

(d) The output of a decoder is a binary code for N-of-1 output

The question was posed to me by my school principal while I was bunking the class.

Asked question is from Encoders in portion Combinational Circuits of Digital Circuits

Answer 1

Right choice is (a) The output of an encoder is a binary code for 1-of-N input

For explanation I would say: An encoder is a combinational circuit encoding the information of 2^n input lines to n output lines, thus producing the binary equivalent of the input. It performs the opposite operation of a decoder which results in 2^n outputs from n inputs. Thus, an encoder different from a decoder because of the output of an encoder is a binary code for 1-of-N input.