D Flip-Flop Implementation Without Reset: Verilog Code and Simulation

This page details a D flip-flop implementation without a reset function, including its symbol, Verilog code, test bench, simulation results, and RTL schematic.

Symbol

Verilog Code

Here’s the Verilog code for a D flip-flop without a reset:

module d_flip_flop(data_in, data_out, clock);
  input data_in;
  input clock;
  output reg data_out;

  always @(posedge clock)
  begin
    data_out <= data_in;
  end
endmodule


## Test Bench

This test bench is used to verify the functionality of the D flip-flop.

```verilog
module Tb_d_flip_flop();
  reg data_in;
  reg clock;
  wire data_out;

  d_flip_flop UUT(.data_in(data_in), .data_out(data_out), .clock(clock));

  initial begin
    // Initialize Input Stimulus
    data_in = 0;
    clock = 0;
  end

  always #100 clock = ~clock; //Stimulus

  initial begin
    #100 data_in = 1'b0;
    #100 data_in = 1'b1;
    #600 data_in = 1'b0;
    #500 data_in = 1'b1;
    #200 data_in = 1'b0;
    #100 $stop;
  end
endmodule

Simulation

The simulation results demonstrate the D flip-flop’s behavior over time. The output data_out follows the input data_in on the rising edge of the clock signal.

RTL Schematic

This is the Register-Transfer Level (RTL) schematic for the D flip-flop. It visually represents the design’s structure and connections.