Dual‐channel pre‐regulator structure for the bandgaps in high step‐down DC‐DC converters

Abstract

High step‐down DC‐DC converters require a robust and low power pre‐regulated supply for bandgap reference. This paper proposes a structure that comprised of two current paths to achieve energy efficient pre‐regulation under high and low input voltage conditions. The design eliminated large size resistors for current limiting which is usually required for high input supplies. The presented pre‐regulator structure combined with the bandgap circuit was realized with the TSMC 180‐nm BCD process. The measured results show the proposed structure has a wide input voltage range of 3.5–45 V, a temperature coefficient of 5.63 ppm/°C and typical average current consumption of 1.1 μA.