Flip-Flop Conversion in DLD
Flip-Flop Conversion is a technique used in Digital Logic Design (DLD) to make one type of flip-flop work like another type of flip-flop. This is done by connecting additional logic gates to the inputs of the available flip-flop.
For example, if a circuit requires a D Flip-Flop but only a JK Flip-Flop is available, we can add suitable logic to the JK inputs so that it performs the same operation as a D Flip-Flop.
Types of Flip-Flops
There are four main types of flip-flops used in Digital Logic Design (DLD).
- SR Flip-Flop is used for setting and resetting the output.
- JK Flip-Flop performs set, reset, and toggle operations.
- D Flip-Flop is mainly used for storing and transferring one bit of data.
- T Flip-Flop is mainly used for toggling and counting operations.
Types of Flip-Flop Conversion in DLD
The common flip-flop conversions studied in DLD are:
1. SR to JK Flip-Flop
In SR to JK conversion, an SR Flip-Flop is modified to behave like a JK Flip-Flop. Additional logic is connected to the S and R inputs so that the SR Flip-Flop follows the required JK operation, including the toggle condition.
2. SR to D Flip-Flop
In SR to D conversion, the inputs of the SR Flip-Flop are arranged so that its output follows the D input. Suitable logic is used to generate the required S and R inputs from D.
3. SR to T Flip-Flop
In SR to T conversion, an SR Flip-Flop is designed to perform the operation of a T Flip-Flop. The input logic makes the flip-flop hold its state when T = 0 and toggle its state when T = 1.
4. JK to SR Flip-Flop
In JK to SR conversion, a JK Flip-Flop is configured to behave like an SR Flip-Flop. The required logic is connected to the J and K inputs to produce the same state changes as the SR Flip-Flop.
5. JK to D Flip-Flop
A JK Flip-Flop can be converted into a D Flip-Flop by applying suitable logic to its J and K inputs. The input connections are designed so that the next state of the JK Flip-Flop follows the D input.
6. JK to T Flip-Flop
In JK to T conversion, the J and K inputs are connected appropriately so that the JK Flip-Flop performs the same function as a T Flip-Flop. It holds its state for T = 0 and toggles for T = 1.
7. D to SR Flip-Flop
In D to SR conversion, a D Flip-Flop is used to perform the function of an SR Flip-Flop. Additional logic is required to generate the appropriate D input according to the required SR operation.
8. D to JK Flip-Flop
In D to JK conversion, the D input is generated using logic based on the J, K, and present-state values. This allows the D Flip-Flop to produce the same next states as a JK Flip-Flop.
9. D to T Flip-Flop
In D to T conversion, the D input is designed so that the D Flip-Flop behaves like a T Flip-Flop. It keeps the same state when T = 0 and changes to the opposite state when T = 1.
10. T to SR Flip-Flop
In T to SR conversion, the T Flip-Flop is provided with suitable input logic to reproduce the required state changes of an SR Flip-Flop.
11. T to JK Flip-Flop
In T to JK conversion, the T input is generated from the JK inputs and the present state. This allows the T Flip-Flop to perform the required hold, set, reset, and toggle operations of a JK Flip-Flop.
12. T to D Flip-Flop
In T to D conversion, the T input is designed according to the D input and present state. This makes the T Flip-Flop produce the same next state as a D Flip-Flop.
Basic Steps for Flip-Flop Conversion
The general steps used for conversion are:
- Identify the required flip-flop.
- Select the available flip-flop.
- Write the truth table of the required flip-flop.
- Use the excitation table of the available flip-flop.
- Determine the required inputs of the available flip-flop.
- Simplify the input equations using Boolean algebra or K-Map.
- Connect the required logic gates to the flip-flop.
In simple words
Flip-Flop Conversion means using one type of flip-flop to perform the function of another type by adding suitable logic at its inputs.