Sequential Circuits (Different types of Adders)


Which of the following statement is not correct?

(i) Carry look ahead is used to speed up parallel addition.

(ii) Two 4-bit parallel adders can be cascaded to construct 8 bit parallel adder.

(iii) Ripple carry adder has addition time independent of number of bits.

(iv) A full adder can be constructed using two half adders and a OR gate.