A wide tuning range ring VCO with low phase noise in 90-nm CMOS

This paper presents a wide tuning range ring voltage-controlled oscillator (VCO) with low phase noise. This design has successfully expanded the linear tuning range of VCO with a novel delay cell architecture. To improve the high frequency performance, the negative delay technology is introduced. The VCO is implemented in 90-nm CMOS with 1.2 V supply voltage. And the post layout simulation results show that this kind of VCO can operate well in the range from 0.63~13.21GHz with -116dBc/Hz phase noise with 10MHz offset.