need help in ring oscillator

[incol]

I am designing a ring oscillator with some inverters, but I find it has a big power supply noise, so how to reduce it, can I modify the circuit to vco? can you give me some circuits?
thanks!

 

[rambus_ddr]

you may seach some patents, there are many these solutions.

 

[aryajur]

I think if you vary the power supply it will be like a VCO. For the noise, maybe you can add more capacitance to the power supply to attenuate the noise.

 

[surianova]

you can connect the ring oscillator through a NMOS to the power supply. By adjusting the gate volatge of the NMOS, you can control the frequency.

Surianova