# (g) Explain the functioning of the D flip-flop and the T flip-flop with the help of a logic diagram and characteristic table. Also, explain the excitation table of this flip-flop.

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D Flip-Flop:

Functioning:

A D flip-flop, or Data flip-flop, is a type of digital storage element that stores and outputs the value of the D (data) input when the clock signal transitions from one state to another (typically rising or falling edge). The logic diagram for a D flip-flop and its characteristic table are as follows:

Logic Diagram:

```

+-----+

D ---->|     |

|  D  |---- Q

CLK--->|  F  |

|  F  |---- Q'

|  L  |

+-----+

```

- \( D \): Data input

- \( Q \): Output

- \( Q' \): Complement of output

- \( CLK \): Clock input

Characteristic Table:

```

| CLK | D | Q(t) | Q(t+1) |

|-----|---|------|--------|

|  ↑  |   |   0  |   D    |

|  ↑  |   |   1  |   D    |

```

- On the rising edge of the clock (\(CLK\)), the output \(Q(t+1)\) becomes the value of the data input \(D\) at that moment.

Excitation Table:

```

| CLK | D | Q(t) | Q'(t) |

|-----|---|------|-------|

|  ↑  | 0 |   0  |   1   |

|  ↑  | 1 |   1  |   0   |

```

- The excitation table describes the inputs that will cause a change in the state of the flip-flop.

T Flip-Flop:

Functioning:

A T flip-flop, or Toggle flip-flop, changes its state (toggles) when the clock signal transitions and the T (toggle) input is 1. The logic diagram and characteristic table for a T flip-flop are as follows:

Logic Diagram:

```

+-----+

T ---->|     |

|  T  |---- Q

CLK--->|  F  |

|  F  |---- Q'

|  L  |

+-----+

```

- \( T \): Toggle input

Characteristic Table:

```

| CLK | T | Q(t) | Q(t+1) |

|-----|---|------|--------|

|  ↑  | 0 |   0  |   0    |

|  ↑  | 0 |   1  |   1    |

|  ↑  | 1 |   0  |   ~Q   |

|  ↑  | 1 |   1  |   ~Q   |

```

- On the rising edge of the clock (\(CLK\)):

- If \(T = 0\), the output remains the same.

- If \(T = 1\), the output toggles (\(~Q\) becomes \(Q\) and vice versa).

Excitation Table:

```

| CLK | T | Q(t) | Q'(t) |

|-----|---|------|-------|

|  ↑  | 0 |   0  |   1   |

|  ↑  | 0 |   1  |   0   |

|  ↑  | 1 |   0  |   1   |

|  ↑  | 1 |   1  |   0   |

```

- The excitation table describes the inputs that will cause a change in the state of the flip-flop.