Digital Systems

Chapter 16

Sequential Circuits for Registers and Counters

OBJECTIVE

We learnt in Chapter 14 the basic memory section elements SR, D, JK and T flip flops. A D flip flop registers at the Q output the bit at D input. This fact can be used to design the multi-bit registers. JK flip-flop, when both J and K equal 1, and T flip flop toggles the Q output on each excitation. This fact can be used to design a divide-by-two element and a multi-bit counter.

We learnt the circuit implementation concepts for the clocked sequential circuits in Chapter 15. Using these, we design a large number of useful circuits, for example, for registers and counters.

We will learn the designs of registers, shift registers, ripple and synchronous counters in this chapter. ...