In examples, a voltage-controlled oscillator (VCO) comprises an inductor; a first pair of transistors having first terminals coupled to a voltage source, second terminals coupled to opposing ends of the inductor, and control terminals coupled to opposing ends of the inductor; and a second pair of transistors having first terminals coupled to ground, second terminals coupled to opposing ends of the inductor, and control terminals coupled to opposing ends of the inductor. The VCO also comprises a first transistor coupled to at least one capacitor, the combination of the first transistor and the at least one capacitor coupled to the inductor in parallel. The VCO further comprises second, third, and fourth transistors coupled to a control terminal of the first transistor, the second transistor coupled to the voltage source, the fourth transistor coupled to ground, and the third transistor configured to receive a ramped voltage.