Abstract
The paper presents a novel dual-band six-phase voltage-control oscillator. The voltage-controlled oscillator (VCO) with a single-ended delay cell architecture has a lower power consumption, a smaller chip area, and a larger output swing than one with a differential delay cell architecture. However, the conventional even-phase outputs ring-type VCO cannot be implemented using single-ended delay cells. In other words, the VCO with single-ended delay cells meets most of the requirements of a sensor circuit system, except even-phase outputs function. This work presents a dual-band six-phase ring type VCO, which is implemented using the proposed single-ended delay cell. The proposed VCO both exhibits the advantages of single-ended delay cells and differential delay cells. The proposed delay cell has a band-switching function, which improves the jitter performance of a VCO in which it is used. The proposed VCO can be operated at 890⁻1080 MHz. The peak-to-peak jitter and the root mean square jitter are the 35.5 ps and 2.8 ps (at 1 GHz), respectively. The maximal power consumption is approximately 6.4 mW at a supply voltage of 1.8 V in a United Microelectronics Corporation 0.18 μm RF CMOS process. The area of the chip is 0.195 × 0.208 mm².