A low‐power CMOS DC‐DC buck converter with on‐chip stacked spiral inductor

Abstract

PurposeThe purpose of this paper is to present a fully integrated power converter. A stacked spiral inductor is applied in a voltage‐mode CMOS DC‐DC converter for the chip miniaturization and low‐power operation.Design/methodology/approachThe three‐layer spiral inductor is simulated with an equivalent circuit and applied to the DC‐DC converter. The DC‐DC buck converter has been fabricated with a standard 0.35 μm CMOS process. The power converter is measured in both experiment and simulation in terms of frequency and electrical characteristics.FindingsExperimental results show that the converter with the stacked spiral inductor operates properly with the inductance of 7.6 nH and mW power range. The measured inductance of the stacked spiral inductor is found to be almost half of the circuit designed value because of the parasitic resistances and capacitances in the spiral inductor.Originality/valueThis paper first introduces the application of the integrated stacked spiral inductor in DC‐DC buck converter for display driver circuit, which requires a low‐power operation. It also shows the fully integrated DC‐DC converter for chip miniaturization.