- 26th September 2006, 17:39 #1
## frequency doubler

i need a simple design of how to make the input frequency become double ...any circuit designer can help? i will appreciate if someone can give me a hand on this.

- 26th September 2006, 18:07 #2

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## frequency multiplier circuit diagram

You need to specify your input frequency range.

- 26th September 2006, 18:07

- 26th September 2006, 23:41 #3

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## simple frequency doubler

a mixer followed by a high-pass filter?

- 27th September 2006, 01:49 #4

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## frequency doubler circuit

Simple frequency doubler for squarewave.

- 27th September 2006, 03:46 #5
## analog frequency doubler

Originally Posted by**10kangstroms**

err....i am very new to circuit design....what specification should i concern about? about the frequency , i think as big as posible lo...hehe...but as long as i can maintain 50% duty cycle is the most important

Added after 31 minutes:

Originally Posted by**bunalmis**

will the output have a 50% duty cycle?

- 27th September 2006, 03:46

- 27th September 2006, 05:34 #6

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## frequency doubler design

Hi

The are many methods for doubling a frequency

it depends on

1 the type of signal (square or sine or ...)

2 The range of the frequency (very low, low, medium, high, very high, hyper...)

3 The stability of the frequence you want to double (is it a single frequency ar many frequencies) what is the frequency range?

Methods I know are:

1 PLL (Phase locked loop)

2 Non linearity to produce hamonics of the signal (full wave rectifier for example) followed by an adequate filter

2 Mixer (in reality mixers translate the frequency, but you can considerate that Fx2 is the same as F+F) this method is also non linearity...

3 monostables trigged by rise edge and fall edge of the signal (square)

...

Hi

Added after 7 minutes:

I forgot...

If your signal is a random signal (speech for example) you can use FFT (fast fourrier transform) to double its frequency

it depends also if you want a real time response or not

good luck

- 27th September 2006, 10:29 #7

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## frequency multiplier circuit design

Originally Posted by**zhangseong**

100 Mhz no problem you may select fast logic family but I dont suggest this circuit because duty drift by temprature.

PLL seems good solution for you.

- 27th September 2006, 13:45 #8
## square wave frequency doubler

Originally Posted by**bunalmis**

can you help me in this PLL ? i dunno which simulator have this component and what should i connect the PLL...( a circuit diagram connection if can)

is this PLL a frequency multiplier also? to get a 50% duty cycle, i should use another flip-flop circuit to divide the signal ? help please....thanks

Added after 16 minutes:

Originally Posted by**timo67**

1. square wave input

2. square wave output(50%)

3. 100Mhz frequency

can you give a circuit diagram for each of the approach that you gave?

1. for PLL, what simulator can get the component? cadence? Hspice or pspice?

2. full rectifier.....is this AC current to DC current? can this get 50% suare wave

output?

3. for mixer....is this the one Xored 2 signal( one been delayed)?

4. can you give example for the FFT option?

thanks timo67 ...your help is very helpul to me.

- 27th September 2006, 18:18 #9

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## mixer as frequency doubler

100MHz is a relative high frequency

for this reason I think the advice of bunalmis is wise

If you need a very precise duty cycle of 50% you can for example doubel you requency twice untill 400MHz and then divize it by 2 with a JK frequency divider.

good luck

- 28th September 2006, 14:41 #10

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## pll frequency doubler

Use a phase lock loop,

- 4th October 2006, 09:08 #11
## frequency doubler pll

Originally Posted by**bunalmis**

i need more delay like delay a quarter of a input square wave

ragards

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