An Optimum Transient Response Synchronous Buck Converter Employing a Novel Analog Multiplier Controller

An ultrafast step response synchronous buck converter has been developed for battery-powered and hand-held electronic applications. The proposed converter has an impressive settling time of only two clock periods and a 1.8 A output current capability. This fast step response makes the proposed converter an ideal choice for dynamic voltage scaling technique in the mentioned applications. The proposed design utilizes an analog multiplier controller (AMC), which provides an optimum disturbance-damping mechanism to remove any output voltage error in just two clock periods. In addition, the synchronization feature of the AMC buck converter eliminates the electromagnetic interference concern in fast buck converters. In order to realize the proposed controller a multiplier block and a novel residual time generator block are employed. The proposed AMC buck converter achieves a fast 2–2.3 $\mu s$ settling time for 1.3 A load step and a 3–3.5 $\mu s$ settling time for 1 V reference step with 1 MHz of switching frequency. Furthermore, The AMC buck converter has a high output current density of 1.38 A/mm$^{2}$ with 96$\%$ peak efficiency. The proposed design has been implemented in a 180 nm bipolar-CMOS-DMOS (BCD) technology with a die size of 910 $\mu$m × 1500 $\mu$m.