Parallel in Serial Out (PISO) Shift Register

In Parallel In Serial Out (PISO) shift registers, the data is loaded onto the register in parallel format while it is retrieved from it serially. Figure 1 shows a PISO shift register which has a control-line and combinational circuit (AND and OR gates) in addition to the basic register components (flip-flops) fed with clock and … Read more

Parallel in Parallel Out (PIPO) Shift Register

Parallel In Parallel Out (PIPO) shift registers are the type of storage devices in which both data loading as well as data retrieval processes occur in parallel mode. Figure 1 shows a PIPO register capable of storing n-bit input data word (Data in). Here each flip-flop stores an individual bit of the data in appearing … Read more

Data Transfer in Shift Registers

Shift registers are the devices which are used to store and/or shift the bits of the input data word. Here the data bits can be made to enter (or exit) the register in serial/parallel mode in synchronization with the clock pulse. Moreover the data bits within the shift register can be made to change their … Read more

Buffer Register and Controlled Buffer Register

Buffer registers are a type of registers used to store a binary word. These can be constructed using a series of flip-flops as each flip-flop can store a single bit. This means that in order to store an n-bit binary word one should design an array of n flip-flops. Figure 1 shows a 4 bit … Read more

Serial in Parallel Out (SIPO) Shift Register

In Serial In Parallel Out (SIPO) shift registers, the data is stored into the register serially while it is retrieved from it in parallel-fashion. Figure 1 shows an n-bit synchronous SIPO shift register sensitive to positive edge of the clock pulse. Here the data word which is to be stored (Data in) is fed serially … Read more

Bidirectional Shift Register

Bidirectional shift registers are the storage devices which are capable of shifting the data either right or left depending on the mode selected. Figure 1 shows an n-bit bidirectional shift register with serial data loading and retrieval capacity. Initially all the flip-flops in the register are reset by driving their clear pins high. Next R/LÌ… … Read more

Shift Registers

Registers are the devices used to store the data bits. The bits stored in such registers can be made to move within the registers and/or in/out of the registers by applying clock pulses. Such registers are called shift registers. An n-bit shift register can be formed by cascading n flip-flops where each flip-flop stores a … Read more

Universal Shift Registers

Universal Shift Register is a register which can be configured to load and/or retrieve the data in any mode (either serial or parallel) by shifting it either towards right or towards left. In other words, a combined design of unidirectional (either right- or left-shift of data bits as in case of SISO, SIPO, PISO, PIPO) … Read more

Dynamic Shift Register

Shift registers can be classified into two types viz., Static Shift Registers and Dynamic Shift Registers. Static shift registers are composed of flip-flops and are capable of storing the information within them for indefinite period of time. On the other hand, dynamic shift registers comprise of dynamic inverters and employ temporary charge storage techniques and … Read more

Applications of Shift Registers

Delay Lines of Shift Registers Shift registers of Serial In Serial Out (SISO) kind can be used to delay the digital signals by a definite period time. The time delay introduced by the n-bit shift register is equal to n times the inverse of the clock frequency driving the shift register. Very long shift registers … Read more