Single-inductor dual-output (SIDO) DC–DC converters for minimized cross regulation and high efficiency in soc supplying systems

Abstract

A compact size and high efficiency singleinductor dual-output (SIDO) DC-DC converter is proposed. The proposed SIDO DC-DC converter not only provides dual output sources (one buck and one boost outputs) but also has minimized cross regulation without using any external compensation components. Generally speaking, it is important to minimize the number of components and footprint area in the design of SIDO converters. However, usually large external compensation resistors and capacitors are required to stabilize DC-DC converters. Importantly, our proposed hysteresis mode operation can effectively avoid the oscillation problems that may exist in many SIMO designs. Furthermore, the dynamic dc current level like that in the continuous conduction mode (CCM) operation can make the proposed SIDO DC-DC converter achieve high conversion efficiency at light loads owing to small conduction loss. Experimental results show a high efficiency from 85% at light loads to 94% at heavy loads.

Integrated single-inductor buck-boost or boost-boost DC-DC converter with power-distributive control

“…To minimize power consumption, multiple supply voltages and dynamic voltage scaling schemes are widely adopted [2]. Recently, several single-inductor multiple-output (SIMO) DC-DC converters [3][4][5][6][7][8][9][10] have been proposed as the most promising solution to minimize component (inductor and power switch) counts/footprints and production cost. However, there exists many design challenges for the SIMO converters, such as cross-regulation, efficiency, system stability, and flexibility, for achieving better step-down and step-up conversion.…”

“…They can be classified as voltage control [3][4][5], peak current control [6][7] [10], and charge control [8][9]. In terms of inductor current waves, converters are divided into discontinuous conduction mode (DCM) [3] [7], pseudocontinuous conduction mode (PCCM) [4] [8][9], continuous conduction mode (CCM) [5], and DCM/CCM [6].…”

“…They can be classified as voltage control [3][4][5], peak current control [6][7] [10], and charge control [8][9]. In terms of inductor current waves, converters are divided into discontinuous conduction mode (DCM) [3] [7], pseudocontinuous conduction mode (PCCM) [4] [8][9], continuous conduction mode (CCM) [5], and DCM/CCM [6]. They also can be sorted into boost/boost converters [3][4] [6][7], buck/buck converters [5], and hybrid buck/boost converters [8][9][10] by using output voltage types.…”

“…In terms of inductor current waves, converters are divided into discontinuous conduction mode (DCM) [3] [7], pseudocontinuous conduction mode (PCCM) [4] [8][9], continuous conduction mode (CCM) [5], and DCM/CCM [6]. They also can be sorted into boost/boost converters [3][4] [6][7], buck/buck converters [5], and hybrid buck/boost converters [8][9][10] by using output voltage types. For the embedded SIMO DC-DC converter in SoC application, although voltage control is slower than current mode control, it has no external current sensors and good noise immunity.…”

“…Recently, there is a reference [6] proposes ordered power-distributive control (OPDC), which can operate in DCM/CCM, and using only one compensator. Besides, compared with familiar SIMO converters [3][4], this timemultiplexing power-distributive approach of [5][6][7][8][9] has less switching number in one cycle, therefore it increase efficiency. In many applications, there are need for a single-inductor dual-output DC-DC converter with one output voltage set to be lower (buck) and another higher (boost) than the supply voltage.…”