Low frequency voltage controlled oscillator design

[veerubiji]

Hi all,

I want to design low frequency voltage controlled oscillator. My frequency range should be arround 1 KHz to 500 KHz. Can anyone suggest which way is best to achieve this because i have seen many design circuits but all are little bit high in output frequency.

Thanks.

 

[FvM]

Many open specification points:
- waveform
- V/f characteristic, e.g. linear, exponential
- frequency accuracy, V/f linearity

 

[veerubiji]

Many open specification points:
- waveform
- V/f characteristic, e.g. linear, exponential
- frequency accuracy, V/f linearity

I am looking for square wave from, linear V/f characteristic and more temperature stability as well as accuracy is also important.

 

[schmitt trigger]

The VCO section of a CD4046 IC can be used for exactly the purpose you want. Stability will be determined in large part by the quality of the timing capacitor and the two frequency setting resistors. Plus a well regulated supply is also a must.

An even more linear V/F can be built with a LM331, but does require more components.

Google their respective datasheets.

 

[KlausST]

Hi,

AD7740, AD7741, AD654, VFC32, ADVFC32...

Klaus