The master-slave flip-flop (MS-FF) is a fundamental building block in digital electronics, used for storing and manipulating binary data.
It overcomes the limitations of simple flip-flops by eliminating race-around conditions, resulting in more reliable and predictable behavior.
Concept:
- A MS-FF consists of two interconnected flip-flops: a master and a slave.
- The master, triggered by the clock’s active edge, captures the input data.
- The slave, triggered by the opposite edge, latches the data captured by the master.
- This separation ensures proper data transfer even when the input changes during the clock pulse.
Structure:
- Master and Slave Flip-Flops: These can be JK, D, T, or any other type of flip-flop, depending on the desired functionality.
- Clock and its Inverter: The master receives the clock signal directly, while the slave receives its inverted counterpart.
- Interconnections: The master’s output is connected to the slave’s input, and vice versa. This creates a feedback loop for data transfer.
Working:
1. Master Active (Clock High):
- Master captures the input data on the clock’s rising edge.
- Slave remains unaffected due to the low clock signal.
2. Slave Active (Clock Low):
- Slave latches the data captured by the master on the falling edge of the clock.
- Master is disabled due to the low clock signal.
This master-slave sequence ensures that the output of the MS-FF always reflects the stable data captured by the master, even if the input changes during the clock pulse.
References:
- Digital Design by Morris Mano (5th Edition): Chapter 5 covers flip-flops in detail, including a dedicated section on MS-FFs with clear explanations and timing diagrams (pp. 252-257).
- Fundamentals of Digital Logic with Verilog Design by Stephen Brown and Zvonko Vranesic (4th Edition): Chapter 4 delves into flip-flops, explaining the MS-FF concept and its advantages over simple flip-flops (pp. 173-178).
- Modern Digital Design and Switching Theory by Eugene D. Hill and David C. Money Harris (2nd Edition): Chapter 5 provides a comprehensive analysis of MS-FFs, including their operation, design considerations, and applications (pp. 228-235).