Sine Wave from Square wave

[vinit2100]

Hi,
I want to generate a sine wave from LTC6900 which gives a square wave output. Please help me designing.

 

[davenn]

hi there

have a look at this article

http://www.ti.com/lit/an/sbfa003/sbfa003.pdf

 

[vinit2100]

That is a Tuned Band Pass Filter IC UAF42. I cant afford that IC . It costs around 15$. any other alternative for this ?

 

[LvW]

Hi,
I want to generate a sine wave from LTC6900 which gives a square wave output. Please help me designing.

If the frequency is fixed you could use a self-designed lowpass or bandpass filter (the necessary order is determined by your distortion requirements: Quality of the sinus signal).
However, a filter that can be tuned together with the varying frequency of the squarewave is harder to realize.

 

[vinit2100]

ok then how will i design a filter ?

 

[KrisBlueNZ]

How about answering some questions first.

Will the frequency of your square wave be variable?

What is the frequency range?

How quickly will the frequency change? Can you tolerate some distortion while the filter settles to a new frequency?

What is your budget?

 

[vinit2100]

Using LTC6900 we can set the output frequency . I will set that frequency to around 2khz. Budget in a sense means, I can afford huge cost IC

 

[LvW]

ok then how will i design a filter ?

There are many, many introductory articles accessible through the Internet which can teach you filter design basics. I don`t think that it is possible to do that in a forum like this.

 

[vinit2100]

ok. l will do and come with my results

 

[BobK]

If you need only a fixed frequency, why not make an oscillator that produces a sine wave instead? It is easier to convert a sine to a square wave than what you are trying to do.

Bob

 

[dablakh0l]

Or build a cheap sine wave generator from an op-amp and some r's and c's

 

[vinit2100]

Ok lets make a oscillator circuit. But my requirement is i don't need the sine waves always. How will i control the oscillator then ? I want to turn ON/OFF oscillator !!!

 

[BobK]

With a switch?

Why don't you tell us what you are trying to do.

Bob