PLL's - Signal Frequency Multiplication 

Thank you for the kind words! I'm happy you are enjoying the videos.

Totally Agree.

I think there are some more products available from Digilent but for me at least, I don't think the extra money is worth it. I mean the AD2 has everything that is needed at decent enough quality for the price.

Hello Hristo! I don't think there would be an issue in going from 32KHz to 3.2MHz (x100) or even more. I mean, its a practical use case to have a ~24MHz quartz and go up to 3GHz, or similar values; but going from 32KHz to 3.2GHz (x10k) might end up creating some problems... I guess other issues would be that you want fast system start up - it takes some time to stabilize the initial oscillator, and then the PLL - if you have the oscillator already at a higher frequency its faster; also if you want to have a low power circuit, adding an extra PLL would not help - if you only need a few tens of MHz, then its easier to just put the quartz in. I guess a bigger practical issue would be the LPF - for 32KHz (or 64KHz) you still need quite a big capacitor, that cannot be built into the silicon chip - you would need an external component, that would limit the number of pins available on the IC. Honestly, I'm not entirely sure why most microcontroller systems use 2 quartzes - a low frequency one and a high frequency one.

Honestly I usually only use the signal generator, oscilloscope and the network analyzer function that puts these 2 together; I rarely use anything else.

Well, you could build the PLL from more basic components; but otherwise I'm not sure how this sort of frequency doubling could be achieved. By the way, is the frequency of the initial narrow spikes known? or does the circuit you wish to build have to work with any input frequency?

@@FesZElectronics I used this Idea www.edn.com/convert-any-signal-to-exactly-50-duty-cycle/ I changed some parts of this circuit a got a doubled 50:50 takt signal. I'm working on inductive power supplies. In order to achieve some targets concerning noise and lower losses you have to use on the secondary side of the system a synchronised frequency of the primer side, sometimes factoring it by 2. I thought, you prbebly know another way to achieve it without using this PLL IC. You are doing a great job producing your videos. 👍I like it.

I think the maximum operating frequency is 20MHz for this component. you probably need a dedicated IC if you want to work with ~100MHz.

@@FesZElectronics I cannot predict the usage area of fm demodulation at low frequencies. Due to the antenna size, Frequency Modulation is done at high frequencies. Therefore, a PLL with a high bandwidth is needed for demodulation. The 4046 is not suitable for this. So why was the 4046 produced? Is there a circuit where it is used in practice?

Normally in a receiver you will not work with the received frequency directly, but rather with an intermediate frequency - in FM receivers this is usually 10.6MHz.