# Flip flop Conversions

Flip flop Conversions are electronic devices with two stable states and a feedback channel that store 1 bit of information utilizing the clock signal. Latches perform the same operation without a clock signal. Simply put, “Flip-flops are clocked latches”. They store one bit of information and stay in the same state until the clock signal changes the input.

There are four flip-flop types.

• SR flip-flop
• D flip-flop
• JK flip-flop

## T flip-flop

JK and D flip-flops are the most popular. They’re abundant in integrated circuits (ICs). Many JK and D flip-flops are available in the semiconductor market. The few SR flip-flops available as ICs are rarely used.
Sometimes a logic circuit requires rare flip-flops.Converting flip-flops lets us use less popular ones. Some popular flip-flop conversions include

• SR Flip – flop to JK Flip – flop
• SR Flip – flop to D Flip – flop
• SR Flip – flop to T Flip – flop
• JK Flip – flop to SR Flip – flop
• JK Flip – flop to D Flip – flop
• JK Flip – flop to T Flip – flop
• D Flip – flop to SR Flip – flop
• D Flip – flop to JK Flip – flop

A combinational circuit is needed to switch flip-flops. Flip-flop and combinational circuit inputs match. Flip-flop inputs match combinational circuit outputs. Combinational circuit output connects to flip-flop input. See illustration underneath.

### SR Flip – flop to other Flip – flops

We must convert SR to JK flip-flop. Create a combinational circuit with J and K inputs and connect its output to our SR flip-flop input. The outputs match the JK flip-flop.

Create a J/K truth table. QP with two inputs produce 8 truth table combinations. QP is the current state and QN the next after applying the two inputs. QN states are determined for each J, K,QP combination. QN provides state values that jump the JK flip-flop output following the current state when inputs are applied. To calculate QN from QP, write all S and R combinations in the truth table. Our S and R values change the flip flop state from QP to QN.

The conversion table from SR flip – flop to JK flip – flop is shown below.

In order to deduce the Boolean equations of S and R in terms of J and K, we use Karnaugh maps from the above table.

The Boolean equation for S is S = JQ’P.

The Boolean equation for R is R = KQP.

### SR to D switch

Attach D to SR flip-flop to form D. Data is connected directly to S and inverted D to R via NOT gates. K-maps match truth tables. Flip-flop current and complementary outputs are QP and QP’. The combinational circuit should input D and output S and R. The SR flip-flop receives S and R combinational circuits.Below is the SR-to-D flip-flop truth table. To calculate QN output, draw D input and QP output truth tables.

#### SR Flip – flop to T Flip – flop

The truth table can be utilized to design the SR flip-flop-to-T combinational circuit. The combinational circuit has T input, S, and R outputs. This flip-flop has S and R inputs. QP and Q’P are flip-flop output and complement. The truth table combines T and QP to produce QN, the flip-flop’s next state output. The same table lists QN-producing S-R pairings.

### JK Flip – flop to other Flip – flops

A JK-to-SR circuit has S and R inputs and J and K outputs. Actual flip-flop inputs are J and K. This conversion requires S, R, QP, J, and K.QP and QN are the current and next state outputs when S and R are applied. We determine QN states for each S, R, and QP combination. A truth table exists for S, R, and QP inputs. Combine QP, S, and R 8. Find S, R, and QP QN. Writing all J and K values in the truth table gives QP QN.The SR flip-flop is undefined or banned when S and R are high. J and K ignore this pair.Implement SR flip-flop from JK flip-flop using the conversion chart below.

#### JK Flip – flop to D Flip – flop

Combinational circuits transform Data input (D) to JK flip-flop D. The Data input is directly connected to J and the NOT gate-inverted D input to K.A combinational circuit should input D and output J & K. Flip-flops receive J and K’s combinational circuit outputs. Current flip-flop output is QP. Q’P is its complement and QN is the next state output. See below the JK-to-D flip-flop conversion truth table.

#### JK Flip – flop to T Flip – flop

Connect the Toggle input (T) directly to the J and K inputs to convert the JK flip-flop to T. The combinational circuit’s external input is toggle (T). Output links to JK flip-flop input.

### D Flip – flop to other Flip – flops

Build a D-to-SR combinational circuit with S and R inputs and D output. Flip-flop input data (D). Eight S & R and QP combinations draw the truth table. QP and QP’ are the current and complement flip-flop outputsWhen S = 1 and R = 1, the two SR flip-flop inputs are high, invalidating the QP value and setting the Data (D) inputs to ‘Don’t cares’.

#### D Flip – flop to JK Flip – flop

D is the combinational circuit’s output when converting D to JK. Flip-flop input data (D). The truth table lists 8 J, K, and QP input combinations. QP and QP’ are the current and complement flip-flop outputs.The truth table combines J, K, and QP to get QN. Next flip-flop state output is QN. A truth table contains D inputs and QN output.

#### D Flip – flop to T Flip – flop

A combinational circuit employs T as its input and D as its output to convert a D flip-flop to a T. Flip-flop input data (D). A truth table exhibits 4 input T and QP combinations. QP and QP’ are the current and complement flip-flop outputs.T + QP = QN in the truth table. Next flip-flop state output is QN. A truth table contains D inputs and QN output.