“…Therefore, how to extend the linear tuning voltage range and enhance the oscillation frequency without dissipating additional power are critical design issues. In previous works, many researchers have focused on low power consumption in two stage ring VCOs [19,20,21,22] and others focused on linearly or wide frequency tuning range of ring VCOs [23,24,25,26,27,28]. The authors of [19,20] designed the ring VCOs with low supply voltage to reduce power dissipation.…”