clock duty cycle conversion

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nanock

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Hi,
I have two clock outputs, one with 60% duty cycle and the other one with 40% duty cycle. I want to convert one of these, no matter which one will be, to 50% duty cycle.
Is it possible?
How can I convert a 60% or 40% duty cycle to 50% ?

thanks
 

with the same frequency, I imagine, if not, add a divider by 2
 
u means add this two output 60 and 40 % and simply dived by 2 to get 50% duty cycle bro????
 
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    nanock

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These simulations show a divide-by-2 counter. It automatically gives you 50 percent duty cycle (at half the frequency):



These simulations show a 555 IC configured as a 'one-shot', triggered by each incoming clock pulse. It must be adjusted carefully to output the desired pulse length.

 
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rca said:
with the same frequency, I imagine, if not, add a divider by 2
Click to expand...
I must try it but I want the same frequency with just a change in duty cycle.
thanks

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nick703 said:
u means add this two output 60 and 40 % and simply dived by 2 to get 50% duty cycle bro????
Click to expand...
No, I just want to convert one of these 60% or 40% clocks to 50% clocks. All frequencies are the same. Just a little change in duty cycle.

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Thanks about simulations, but it changes the frequency. If you use D-Latch instead of DFF, will the frequency change ? I just want to change the duty cycle to 50%.
 

it is close to an analog design.

We did a project a digital clock multiplier by two (long time ago), so then you could divide by two and have a 50% duty cycle, but you need to be very carefully with the backend steps.
The idea is xor with the same signal on both input, but one input has multiple buffers/delay (25% of the input signal).
 
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    nanock

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Unfortunately I'm not allowed to use analog tricks. But I think there is a solution with xor. I will tell you when ever I reach to a digital solution.
Thanks to all
 

nanock said:
Unfortunately I'm not allowed to use analog tricks. But I think there is a solution with xor. I will tell you when ever I reach to a digital solution.
Thanks to all
Click to expand...
I think that use of duty cycle correction circuit(DCC) is critical. But one can find this helpful if I use DFF for divided by 2 so that I have 50% duty cycle and then utilizing frequency doubler to reach the original frequency.
If there is any other key point please tell me?
thanks
 

Lacking a transition at the 50 percent mark...

Therefore we must start where there is a transition, and construct a time-dependent feature of some kind.

Time-dependent components include coils and capacitors. In other words, analog constructs.

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You mentioned a frequency doubler. Not a bad idea.

This simulation shows what you'll get:



The incoming transitions determine the shape of the output. The output is not at a 50 percent duty cycle.

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Hold the phone, however. Your idea was to get 50 percent duty cycle pulses, at 1/2 the frequency, from a flip flop.

In that case the frequency doubler does provide 50 percent duty cycle output:

 
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In order to use an ordinary frequency doubler, I use an xor gate as below. But one problem I find is the delay cell. This cell must have 50% or 25% delay of input signal period. Can I use shift register as a delay cell?
 

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