Single-inductor Dual-output DC-DC Research Articles

リプルレギュレータ方式による 単インダクタ2出力DC-DC電源

リプルレギュレータ方式による 単インダクタ2出力DC-DC電源

A low cross-regulation and high-efficiency SIDO boost converter with near-threshold start-up

This paper proposes a single-inductor dual-output (SIDO) DC-DC boost converter with Near-threshold Start-up voltage which adopts ordered-power-distributive-control (OPDC) method. A load-dependent feedback loop control is proposed to effectively suppress cross-regulation between the outputs, which is simple and flexible. Meanwhile, a two-step start-up scheme which makes the start-up circuit simpler has been put forward. It makes sure that the SIDO converter can adjust and complete near-threshold start-up depending on different load currents. This SIDO DC-DC converter has been fabricated in 0.18 μm CMOS process. The minimum starting voltage is 0.5 V, and the simulation results show that the cross-regulation suppression circuit successfully reduce the voltage cross-regulation ratios VCR1 and VCR2 to 0.2 mV/mA and 0.11 mV/mA, respectively. In normal operation, both of the output voltages and its corresponding maximum output currents are 1.2 V/40 mA and 1.8 V/40 mA. A maximum conversion efficiency of 91% can be achieved.

Dead-time을 갖는 톱니파 발생기를 이용한 이중 피드백 루프 기반 단일 인덕터 이중 출력 승압형 변압기 설계

이 논문은 Dead-time을 갖는 톱니파 발생기를 이용하여 공통모드와 차동모드 피드백 루프를 구현한 Single-Inductor Dual-Output DC-DC Converter 설계에 관한 내용을 제시하고 있다. 제어회로에는 공통모드와 차동모드 피드백 루프를 Dead-time을 갖는 톱니파 발생기를 이용하여 동시에 사용하였다. 차동모드 피드백 루프에서 duty를 생성하기 위해서 전류 분배기 회로를 사용하여 공통모드 피드백에 의한 duty에 따라 dead-time이 유동적으로 변하는 톱니파형을 만드는 회로인 Dead-time을 갖는 톱니파 발생기를 추가하여 차동모드 피드백 회로를 구성하였다. 0.35um 공정을 사용하여 설계한 SIDO DC-DC Converter는 2.5V 입력으로부터 2.8V와 4.2V의 전압을 출력하며 최대 전력변환 효율은 95%이다. 출력간의 Cross regulation은 출력전류가 2배씩 증가할 경우 Boost1과 Boost2의 출력전압은 각각 3.57%, 4% 수준을 보이고 있다. This paper presents a control method of Single-Inductor Dual-Output DC-DC Converter using Common mode feedback and differential feedback loops. To generate duty used for differential mode feedback loop, this paper propose relative sawtooth circuit using current divider circuit which makes ramp signal with variable dead-time. Two outputs of the Single-Inductor Dual-Output DC-DC Converter are specified for 2.8 V and 4.2 V with input voltage 2.5 V. The maximum conversion efficiency of designed SIDO DC-DC Converter is 95% at total output power of 539mW. Cross regulations of Boost1 and Boost2 are 3.57% and 4% each, when increasing twice times output current.

A Variable Multiple-Output DC-DC Buck Converter with Time-Multiplexing

This paper presents a variable current-controlled single-inductor dual-output DC-DC buck converter depending on difference loading currents in standard 0.18-μm CMOS n-well process. We intend for compensate system and according each loading current to make suitable dual cycle. Two outputs are specified at 1.8V and 1.2V operated at 800 KHz, the power conversion efficiency reaches 82%. The chip occupies 1.73 × 1.1 mm2.