Hello all,

I have assembeled the underlined below circuit on a bread board and it is working well.
How ever the output of the 4046(im not able to simulate the 4046) is a square wave which i want to convert back to a sine wave,at the moment i have used a series of low pass filters to do so.
Is there any better way to do this?
I have had my eye on the UAF42.Would the UAF42 be able to achieve this without the external RC and buffer components?

Many thanks

 

Hello all,

I have assembeled the underlined below circuit on a bread board and it is working well.
How ever the output of the 4046(im not able to simulate the 4046) is a square wave which i want to convert back to a sine wave,at the moment i have used a series of low pass filters to do so.
Is there any better way to do this?
I have had my eye on the UAF42.Would the UAF42 be able to achieve this without the external RC and buffer components?

Many thanks

What frequency (or frequency range) are you designing for?

 

Is there any better way to do this?

In a similar thread to this, DDS (Direct Digital Synthesis) has been suggested. The problem with using low pass filters is that they're fine for a single input frequency, but if you want sines of various frequencies the amplitude of your wanted sine signal reduces as the input frequency increases.

 

What frequency (or frequency range) are you designing for?

My frequency range is between 45Hz to 55 Hz

In a similar thread to this, DDS (Direct Digital Synthesis) has been suggested. The problem with using low pass filters is that they're fine for a single input frequency, but if you want sines of various frequencies the amplitude of your wanted sine signal reduces as the input frequency increases.

My center frequency is 50 Hz with a margin of 5 Hz on both sides.
The "in" in my simulation is from the secondary of a step down traansformer.The 4046 as you may have gussed is used to generate a phase locked loop which synchronizes with the "in".
I searched the DDS forums on analog devices website for a similar solution ,(even posted on it,but no response),i want to avoid use of a microcontroller for this application. Most of the DDS wave form generator chips require a controller to generate any wave form!

 

Why do you want to convert the signal back to a sinewave?
The 4046 phase-comparator will compare a sinewave with a square-wave.