A 28nm CMOS 1.3-GHz Low Phase Noise Gm-Boosted Cross-Coupled DCO for Automotive Radar Applications

In this paper, the first Gm-Boosted Cross-CoupledDCO in a 28-nm CMOS technology for automotive radar applicationsis reported. The use of 28-nm CMOS technology poses newchallenges on low phase noise DCO design. Supply voltages... [ view full abstract ]

In this paper, the first Gm-Boosted Cross-Coupled

DCO in a 28-nm CMOS technology for automotive radar applications

is reported. The use of 28-nm CMOS technology poses new

challenges on low phase noise DCO design. Supply voltages are

further reduced to 0.9 V in order to not to damage the devices,

resulting in a lower voltage swing and higher achievable phase

noise with respect to higher supply voltage designs. In addition,

very stringent local density rules, even required to meet in small

inductor and capacitor areas, add an extra difficulty to layout a

DCO, so the way the inductor is laid out becomes an essential

step during the design to obtain the desired performances. The

presented DCO achieves a phase noise equal to -127 dBc/Hz at

1 MHz offset from its central oscillation frequency of 1.3 GHz,

achieves a tuning range of 1.25 GHz to 2.25 GHz with a fine

frequency resolution of 1.1 MHz and consumes the total power

of 5 mW using a 0.9-V supply. The layout area is 280 �m �

530 �m including the inductor. Finally, the tuning range-based

Figure Of Merit (FOMT ) is equal to 194 dB.