Question

All shift registers are made of flip-flops

• A. JK
• B. RS
• C. D
• D. T

Hint:

Remember: D is for Data. Since shift registers move Data, they use D flip-flops. T flip-flops are used for counters because they Toggle.

Answer 1

The Correct Option is C

A shift register is a sequential logic circuit used primarily for storing or delaying data, or for converting between serial and parallel data formats. 1. Function of a Shift Register: A shift register consists of a chain of flip-flops connected in such a way that the output of one flip-flop becomes the input of the next. On every clock pulse, the bit stored in each flip-flop "shifts" one position down the line.

2. Why the D Flip-Flop? The

D (Data or Delay) flip-flop is the ideal choice for shift registers because:

• It captures the value of the input (D) at the clock edge and holds it until the next clock pulse.

• It does not have complex toggle or set/reset conditions that would interfere with the simple transfer of data from stage to stage.

• It provides the exact one-clock-cycle delay necessary for shifting operations.

3. Construction: An $n$-bit shift register requires $n$ D-type flip-flops. While JK flip-flops could be converted to D-type to perform this task, shift registers are fundamentally defined by the "Data" transfer characteristic of the D-type.