This paper presents a 220-MHz pulse width modulation (PWM) fully integrated KY dc-dc step-up converter utilizing bondwire as power inductor, with discontinuous conduction mode (DCM) calibration control. We develop the first DCM closed-loop PWM controller for the KY converter, including: 1) its parameter design; 2) a DCM closed-loop voltage mode control with Type II compensator; 3) a zero current detection method to activate DCM control; and 4) a DCM calibration loop. Fabricated in 65-nm CMOS, the designed KY converter core occupies 0.93 mm(2) and achieves an output conversion range of 1.5-2 V from a 1.2-V input. The measured peak efficiency is 75.2% at 97.5 mW. With a 500-ps rising/falling time of the load current step (56 mA), the undershoot/overshoot is 245/205 mV at 146-/140-ns recovery time, and the dc-dc converter achieves a settling time per load transient step of 2.6 ns/mA, which is competitive with the state-of-the-art boost converters.