一种工作在近阈值电源电压下的高分辨率数控振荡器

An high-resolution digitally controlled oscillator under near-threshold supply

文中提出了一种工作在近阈值电源电压下的LC数控振荡器(Digitally Controlled Oscillator, DCO),该振荡器采用PMOS管和NMOS管的交叉耦合结构实现了电流复用,降低了DCO的工作电流。DCO基于一种多阶电容桥接技术,在不采用ΔΣ调制器且不增加DCO功耗的前提下将单位可变电容值由3.2 fF减小到6.7 aF,提高了DCO的分辨率。文中提出的LC-DCO在130 nm CMOS工艺下进行了流片验证,测试结果显示,在0.5 V电源电压,输出频率为2.4 GHz时,电路功耗为0.425 mW,分辨率为9 kHz, 1 MHz频偏处的相位噪声为-122.2 dBc/Hz, FoM为193.52 dB。

A LC digitally controlled oscillator( LC-DCO) under near-threshold supply is proposed.The cross-coupling structure of PMOS and NMOS transistors is used to achieve current multiplexing, thus reducing the current of the DCO.A multi-stage capacitance attenuation technology is used for improving the resolution of the DCO without ΔΣ modulator and the power consumption of the DCO is reduced.And the unit variable capacitance value is reduced from 3.2 fF to 6.7 aF.The resolution is 9 kHz when the output frequency is 2.4 GHz.The LC-DCO is tested in 130 nm CMOS process.The measurement results show that the power consumption of the circuit is 0.425 mW at 0.5 V supply voltage, the phase noise is-122.2 dBc/Hz, and the FoM is 193.52 dB.