How I can implement phase shifter of 90 degree without using Flip flops?

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Anonymous
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Hi All,

   

I am looking for a way through which I can shift my signal by 90 degrees. I want to avoid using flip flops.

   

Looking forward to your suggestions.

   

 

   

Regards

   

Awais

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odissey1
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maknight,

   

you can use PLL to get 90 deg shift

   

http://www.edn.com/design/analog/4411037/Demystifying-the-PLL

   

View solution in original post

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Bob_Marlowe
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"shift my signal by 90 degrees" So, what is your signal? Where does it come from. I just assume it is a digital signal, is it?

   

And what is the reason you do not want to use a FF.

   

 

   

Bob

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Anonymous
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Thank you, Bob, for your reply!

   

Correct, It's a digital square wave signal coming out of the comparator and entering into the LO input of the Mixer.

   

I am avoiding using flip flop because, in my full schematic design, I get half of the frequency at the output of the flip-flop.

   

I was thinking about shift register but I am not sure how should I use it. Maybe a shift register with the not gate? What do you think could be the best thing i can do about it?

   

Looking for your reply!

   

Regards

   

Awais

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Bob_Marlowe
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Frequency range?

   

 

   

Bob

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Anonymous
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It's about 100 KHz

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Bob_Marlowe
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You could try to measure signal high and low time (or frequency and duty cycle) and generate a 90 degrees shifted signal using a PWM.

   

 

   

Bob

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Anonymous
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This could be possible but I would not be flexible if my input frequency would change for some reason.

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Bob_Marlowe
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I thought for a constantly measure of a single cycle input signal and controlling the PWM. Can probably done with a 100kHz signal. What are the precision restrictions you have got? And: What is the lowest frequency to handle?

   

 

   

Bob

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Anonymous
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I can maximally go town to 90KHz.

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Bob_Marlowe
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Quite tough, give it a try...

   

 

   

Bob

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odissey1
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maknight,

   

you can use PLL to get 90 deg shift

   

http://www.edn.com/design/analog/4411037/Demystifying-the-PLL

   

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