The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）,...The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）, negative word-line voltage （VinyL） and half-VDD voltage （VHDo） generator. To generate a process voltage temperature （PVT）-insensitive VpWL and VNWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective voltage level detectors. Also, a VOWL regulator and a VNWL charge pump were proposed for a small-area and low-power design. The proposed VpwL regulator can provide a large driving current with a small area since it regulates an input voltage （VCI） from 2.5 to 3.3 V. The VmvL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped charges to VNWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory measurement results.展开更多
The most commonly used modulation for an isolated modular multilevel DC-DC converter(IMMDCC)is quasi-square-wave modulation(QSWM).However,in order to realize soft-switching,QSWM-IMMDCC usually needs to increase the ph...The most commonly used modulation for an isolated modular multilevel DC-DC converter(IMMDCC)is quasi-square-wave modulation(QSWM).However,in order to realize soft-switching,QSWM-IMMDCC usually needs to increase the phase-shifting angle or reduce the voltage amplitude ratio,which will not only increase the conduction loss but also require more passive components.This paper proposes an improved quasi-square-wave modulation(IQSWM),which generates ripple current through the non-complementary output of the upper and lower arms.Compared with QSWM-IMMDCC,the ripple current can make IQSWM-IMMDCC realize soft-switching under the conditions of a smaller phase-shifting angle and larger voltage amplitude ratio.The decrease of the phase-shifting angle can improve the power factor of the AC link and reduce the inductance in the AC link,and the increase of the voltage amplitude ratio can increase the fundamental wave voltage of the AC output and reduce the capacitance of the sub-module.In addition,IQSWM can also adjust the ripple current according to changes in output power,thereby broadening the range of soft-switching.Finally,the ripple currents generated by multiple parallel IQSWM-IMMDCCs can offset each other,thereby preventing any impact on the DC output.The simulation results prove the correctness and effectiveness of IQSWM.展开更多
High efficiency and fast dynamic response are two main control objectives for dual active bridge(DAB)DC-DC converters. Traditional extended phase shift(EPS)control can significantly enhance the conversion efficiency o...High efficiency and fast dynamic response are two main control objectives for dual active bridge(DAB)DC-DC converters. Traditional extended phase shift(EPS)control can significantly enhance the conversion efficiency of DAB DC-DC converters by reducing current stress;however, it cannot fulfill fast dynamic response requirements. In this paper, a novel hybrid control scheme consisting of EPS control and direct power control(DPC),named as EPS-DPC, is proposed. EPS-DPC control has salient features in both efficiency and dynamic performance. In order to verify the outstanding performance of the proposed EPS-DPC scheme, an experimental comparison was carried out on a scale-down DAB DC-DC converter among several control strategies, including single phase shift control with traditional voltage-loop(SPS-TVL), EPS control with traditional voltage-loop(EPSVTL), and EPS-DPC. Experimental results have been high consistent with theoretical analysis, and verified these advantages of the proposed EPS-DPC scheme.展开更多
基金supported by the Second Stage of Brain Korea 21 Projectsfinancially supported by Changwon National University in 2011-2013
文摘The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）, negative word-line voltage （VinyL） and half-VDD voltage （VHDo） generator. To generate a process voltage temperature （PVT）-insensitive VpWL and VNWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective voltage level detectors. Also, a VOWL regulator and a VNWL charge pump were proposed for a small-area and low-power design. The proposed VpwL regulator can provide a large driving current with a small area since it regulates an input voltage （VCI） from 2.5 to 3.3 V. The VmvL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped charges to VNWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory measurement results.
文摘The most commonly used modulation for an isolated modular multilevel DC-DC converter(IMMDCC)is quasi-square-wave modulation(QSWM).However,in order to realize soft-switching,QSWM-IMMDCC usually needs to increase the phase-shifting angle or reduce the voltage amplitude ratio,which will not only increase the conduction loss but also require more passive components.This paper proposes an improved quasi-square-wave modulation(IQSWM),which generates ripple current through the non-complementary output of the upper and lower arms.Compared with QSWM-IMMDCC,the ripple current can make IQSWM-IMMDCC realize soft-switching under the conditions of a smaller phase-shifting angle and larger voltage amplitude ratio.The decrease of the phase-shifting angle can improve the power factor of the AC link and reduce the inductance in the AC link,and the increase of the voltage amplitude ratio can increase the fundamental wave voltage of the AC output and reduce the capacitance of the sub-module.In addition,IQSWM can also adjust the ripple current according to changes in output power,thereby broadening the range of soft-switching.Finally,the ripple currents generated by multiple parallel IQSWM-IMMDCCs can offset each other,thereby preventing any impact on the DC output.The simulation results prove the correctness and effectiveness of IQSWM.
基金supported by the National Natural Science Foundation of China(No.51577160)
文摘High efficiency and fast dynamic response are two main control objectives for dual active bridge(DAB)DC-DC converters. Traditional extended phase shift(EPS)control can significantly enhance the conversion efficiency of DAB DC-DC converters by reducing current stress;however, it cannot fulfill fast dynamic response requirements. In this paper, a novel hybrid control scheme consisting of EPS control and direct power control(DPC),named as EPS-DPC, is proposed. EPS-DPC control has salient features in both efficiency and dynamic performance. In order to verify the outstanding performance of the proposed EPS-DPC scheme, an experimental comparison was carried out on a scale-down DAB DC-DC converter among several control strategies, including single phase shift control with traditional voltage-loop(SPS-TVL), EPS control with traditional voltage-loop(EPSVTL), and EPS-DPC. Experimental results have been high consistent with theoretical analysis, and verified these advantages of the proposed EPS-DPC scheme.
