Novel digitally programmable multiphase voltage controlled oscillator and its stability discussion

• The MVCO could provide six or eight different phase sinusoidal signals.
• The frequency tuning range of the six-phase MVCO is from 788.5 MHz to 2.506 GHz.
• The frequency tuning range of the eight-phase MVCO is from 558.9 MHz to 1.512 GHz.

In this paper, a novel programmable current-mode multiphase voltage controlled oscillator (MVCO) is presented. The proposed MVCO consists of four identical first-order all-pass filters, which act for delay cells of the MVCO. By switching the programmable MOS switches on and off, the MVCO can provide six or eight different phase sinusoidal signals. Theoretically, the proposed MVCO can provide 2n (n ⩾ 3) different phase sinusoidal signals by cascading n (n ⩾ 3) first-order all-pass delay cells. Compared with previous reported works, this MVCO has the advantages of lower supply voltage, lower power consumption, a smaller chip area and more multi-outputs than other reported works. In particularly, by using programmable switches and cascading more first-order all-pass delay cells, the proposed MVCO can theoretically provide 2n (n ⩾ 3) different phase sinusoidal signals.