I am designing an integrated PLL and i have started with the VCO. I have decided to use a ring VCO (attached) because it is simpler as this is my first real design and i don't know much.
1. I want to know if this is a good enough design for a STANDARD PLL that works.
2. I have realised that even though the frequency of oscillation changes with the tuning voltage, the amplitude also changes as well. Is that how it is supposed to behave?

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