FInding VCOs

[Shalom]

Hi, i am looking for a VCO that has a working frequency of 20MHz to 60MHz. I am building a PLL circuit. PLease advise as i have difficulty in finding VCOs in this range. I do not mind a frequency range that is larger than i stated as long as the working range is within 20 to 60MHz.

Thnaks in advance

 

[Nigel Goodwin]

Hi, i am looking for a VCO that has a working frequency of 20MHz to 60MHz. I am building a PLL circuit. PLease advise as i have difficulty in finding VCOs in this range. I do not mind a frequency range that is larger than i stated as long as the working range is within 20 to 60MHz.

A VCO is usually operated by a varicap diode across a tuned circuit, however your range is exceptionally wide to cover in a single range.

As possibilities I would suggest either splitting it into more than one range, or moving the frequency far higher and down-converting to the range you want.

 

[Roff]

Hi, i am looking for a VCO that has a working frequency of 20MHz to 60MHz. I am building a PLL circuit. PLease advise as i have difficulty in finding VCOs in this range. I do not mind a frequency range that is larger than i stated as long as the working range is within 20 to 60MHz.

Thnaks in advance

The datasheet for LTC6905 says it can be used as a VCO (scroll all the way to the end of the datasheet).

 

[Shalom]

Hi tks nigel and ron for the reply. I will discuss it with my professor and see which can fullfill our requirements. Thanks alot

 

[JimB]

If you want to buy a VCO, have a look at www.minicircuits.com they make VCO modules (amongst other things).

Your tuning range of 20 to 60 Mhz could be a bit of a problem. A 3 to 1 frequency ratio requires a capacitance ratio of 9 to 1. This could be stretching things a bit in terms of what is achievable in practice with varicap diodes.

JimB