Effects of random jitter on high-speed CMOS oscillators

A comparison is made of the effects of device noise on the jitter of three different high-speed voltage-controlled ring oscillators. These comparisons show that oscillator architecture plays a significant role in jitter performance and that in high-speed oscillators, the device noise contributed when the MOS transistors are operating in the triode region is substantial. These comparisons also show minimal differences in the noise predicted by the simple and widely used noise model and that predicted by the more complete but more complicated model recently introduced by Sodini and Hellums.