Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Circuit for Edge Detection of a digital signal

Status
Not open for further replies.

abhaybonds

Newbie level 4
Joined
Dec 30, 2009
Messages
7
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,369
Hi,
I want to design a self timed circuit in which two inputs affect the output. When input1 goes from 0 to 1, the output becomes 1 and when input 2 goes from 1 to 0, the output becomes 0. There is no change in the output for other transitions of the inputs.
It looks easy but I am not able to think of a suitable circuit.
I would be thankful if anybody could help me!!

Thank You
 

Hi,

I dont know whether u are in need of a digital circuit or a HDL. I have attached the HDL code. You can even translate this to a circuit.

always@(posedge clk or negedge rst)
begin
if(~rst)
a_f <= 1'b0;
else
a_f <= input_a;
end
assign zero_to_one_transition = !a_f && input_a;
always@(posedge clk or negedge rst)
begin
if(~rst)
b_f <= 1'b0;
else
b_f <= input_b;
end
assign one_to_zero_transition = b_f && ! input_b;
always@(posedge clk 0r negedge rst)
begin
if(~rst)
output_f <= 1'b0;
else if(zero_to_one_transition)
output_f <= 1'b1;
else if(one_to_zero_transition)
output_f <= 1'b0;
end

endmodule
 

Hi,
I wanted the circuit. I dont have any HDL software to convert it into circuit. Any other ideas?
Anyways thanks for the reply.

Thank you
 

Circuit.png

Hope it helps

- - - Updated - - -

Circuit.png

Hope it helps
 
Hi,
Thanks for giving circuits. But I was looking for a circuit without any external clock.
Anyways I figured it out. The idea lies in creating a short pulse from the inputs when they change levels and use these pulses to trigger a SR latch.
Thanks a lot for the help.

Thank You
Abhay
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top