- SIPO Shift Register Definition: A Serial in Parallel Out (SIPO) shift register is a device that stores data serially and retrieves it in parallel.
- Data Shifting: Data bits move from one flip-flop to the next with each clock pulse, enabling sequential storage and parallel retrieval.
- Right-Shift Operation: In a right-shift SIPO register, data shifts from left to right with each clock tick.
- Left-Shift Operation: In a left-shift SIPO register, data shifts from right to left while maintaining the same working principle.
- Clock Pulse Dependency: The movement and storage of data depend on the rising edge of the clock pulse.
A Serial In Parallel Out (SIPO) shift registers loads bits one at a time and presents the stored word on all outputs at once. Figure 1 is an n-bit rising-edge SIPO shift register. Serial data enters the first flip-flop (D1 of FF1). Every later stage except FF1 is driven by the one before it: FF2 takes the output of FF1. In this shift register the stored word is read as Data out from Q1 to Qn.
Clear the register first by driving every clear pin high. Then put the first bit B1 on D1 of FF1.
That bit B1 is stored in FF1 and appears at Q1 on the first clock. On the second clock B1 moves into FF2 at Q2 while B2 enters FF1. Each later clock shifts the word one bit right and accepts a new input bit. All stored bits can be read at once from the flip-flop outputs.
The full n-bit word is therefore present on the outputs at the rising edge of the nth clock. Table I and Figure 2 show that motion.
Figure 1 shifts left to right. Reverse the chain and the same idea gives a left-shift SIPO (Figure 3). After n clocks the word sits as Bn down to B1 in Qn down to Q1, that is Q1 = B1, Q2 = B2 … Qn = Bn at the nth clock.
