This paper presents an AOT-controlled(adaptive-on-time,AOT)valley-current-mode buck converter for portable application.The buck converter with synchronous rectifier not only uses valley-current-mode control but also p...This paper presents an AOT-controlled(adaptive-on-time,AOT)valley-current-mode buck converter for portable application.The buck converter with synchronous rectifier not only uses valley-current-mode control but also possesses hybridmode control functions at the same time.Due to the presence of the zero-current detection circuit,the converter can switch freely between the two operating modes without the need for an external mode selection circuit,which further reduces the design difficulty and chip area.The converter for the application of high power efficiency and wide current range is used to generate the voltage of 0.6–3.0 V with a battery source of 3.3–5.0 V,while the load current range is 0.05–2 A.The circuit can work in continuous conduction mode with constant frequency in high load current range.In addition,a stable output voltage can be obtained with small voltage ripple.In pace with the load current decreases to a critical value,the converter transforms into the discontinuous conduction mode smoothly.As the switching period increases,the switching loss decreases,which can significantly improve the conversion efficiency.The proposed AOT controlled valley current mode buck converter is integrated with standard 0.18μm process and the simulation results show that the converter provides well-loaded regulations with power efficiency over 95%.When the circuit switches between the two conduction modes drastically,the response time can be controlled within 30μs.The undershoot voltage is controlled within 25 mV under a large current hopping range.展开更多
The boost type power supplies are widely used in portable consumer electronics to step up the input voltage to adapt for the high voltage applications like light-emitting diode(LED) driving and liquid crystal display(...The boost type power supplies are widely used in portable consumer electronics to step up the input voltage to adapt for the high voltage applications like light-emitting diode(LED) driving and liquid crystal display(LCD) biasing.In these applications,a regulator with small volume,fewer external components and high efficiency is highly desired.This paper proposes a projected off-and on-time boost control scheme,based on which a monolithic IC with an on-chip VDMOS with 0.2 Ω on-state resistance RDS-ON was implemented in 1.5 μm bipolar-CMOS-DMOS(BCD) process.A 12 V,0.3 A boost regulator prototype is presented as well.With projected off-time and modulated on-time in continuous conduction mode(CCM),a quasi fixed frequency,which is preferred for ripple control,is realized.With projected on-time and modulated off-time in discontinuous conduction mode(DCM),pulse frequency modulation(PFM) operation,which is beneficial to light load efficiency improvement,is achieved without extra control circuitry.Measurement results show that an efficiency of 3% higher than that of a conventional method under 0.5 W output is achieved while a step load transient response comparable to that of current mode control is maintained as well.展开更多
A current-mode buck DC-DC controller based on adaptive on-time （AOT） control is presented. The on-time is obtained by the techniques of input feedforward and output feedback, and the adaptive control is achieved by ...A current-mode buck DC-DC controller based on adaptive on-time （AOT） control is presented. The on-time is obtained by the techniques of input feedforward and output feedback, and the adaptive control is achieved by a sample-hold and time-ahead circuit. The AOT current-mode control scheme not only obtains excellent transient response speed, but also achieves the independence of loop stability on output capacitor ESR. In addition, the AOT current-mode control does not have subharmonic oscillation phenomenon seen in fixed frequency peak current-mode control, so there is no need of the slope compensation circuit. The auto-skip pulse frequency modulation （PFM） mode improves the conversion efficiency of light load effectively. The controller has been fabricated with UMC 0.6-μm BCD process successfully and the detailed experimental results are shown.展开更多
A 1500 mA,10 MHz self-adaptive on-time （SOT） controlled buck DC-DC converter is presented. Both a low-cost ripple compensation scheme （RCS） and a self-adaptive on-time generator （SAOTG） are proposed to solve the...A 1500 mA,10 MHz self-adaptive on-time （SOT） controlled buck DC-DC converter is presented. Both a low-cost ripple compensation scheme （RCS） and a self-adaptive on-time generator （SAOTG） are proposed to solve the system stability and frequency variation problem. Meanwhile a self-adaptive power transistor sizing （SAPTS） technique is used to optimize the efficiency especially with a heavy load. The circuit is implemented in a 2P4M 0.35μm CMOS process. A small external inductor of 0.47 μH and a capacitor of 4.7 μF are used to lower the cost of the converter and keep the output ripple to less than 10 mV. The measurement results show that the overshoot of the load transient response is 8 mV @ 200 mA step and the dynamic voltage scaling （DVS） performance is a rise of 16/zs/V and a fall of 20 μs/V. With a SAPTS technique and PFM control, the efficiency is maintained at more than 81% for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%.展开更多
A 10 MHz ripple-based on-time controlled buck converter is presented. A novel low-cost dual ripple compensation, which consists of coupling capacitor compensation and passive equivalent series resistance compensation,...A 10 MHz ripple-based on-time controlled buck converter is presented. A novel low-cost dual ripple compensation, which consists of coupling capacitor compensation and passive equivalent series resistance compensation, is proposed to achieve a fast load transient response and robust stability simultaneously. Implemented in a 2P4M 0.35 um CMOS process, the converter achieves fix-frequency output with a ripple of below 10 mV and an overshoot of 10 mV at 400 mA step load transient response. With width optimization of the power transistors in an ultra-heavy load and PFM control in a light load, the efficiency stays at over 83% for a load range from 20 mA to 1.5 A and the peak efficiency reaches 90.16%.展开更多
随着汽车智能化的发展,汽车内的电子控制单元(Electronic Control Unit,ECU)数量激增,因CAN总线自身的特点,挂载在总线上的ECU缺乏必要的安全保护。为此,提出了基于物理不可克隆函数(Physical Unclonable Functions,PUF)的车载网络ECU...随着汽车智能化的发展,汽车内的电子控制单元(Electronic Control Unit,ECU)数量激增,因CAN总线自身的特点,挂载在总线上的ECU缺乏必要的安全保护。为此,提出了基于物理不可克隆函数(Physical Unclonable Functions,PUF)的车载网络ECU身份认证方案。该方案利用PUF的物理特征动态生成密钥,将身份认证划分为两个关联结合阶段,以满足车载网络实时性和安全性的双重需求。在车辆出厂前的非实时场景下,采用数字证书完成ECU间的注册。在车辆启动的实时场景下,基于认证链建立“一次一密”的快速身份认证机制。采用仿真测试对该方案的性能进行了评估,并与其他认证方案进行对比。实验结果表明,该方案可以同时满足车载网络在实时性和安全性方面的需求。展开更多
基金supported by the National Natural Science Foundation of China(No.61974116)。
文摘This paper presents an AOT-controlled(adaptive-on-time,AOT)valley-current-mode buck converter for portable application.The buck converter with synchronous rectifier not only uses valley-current-mode control but also possesses hybridmode control functions at the same time.Due to the presence of the zero-current detection circuit,the converter can switch freely between the two operating modes without the need for an external mode selection circuit,which further reduces the design difficulty and chip area.The converter for the application of high power efficiency and wide current range is used to generate the voltage of 0.6–3.0 V with a battery source of 3.3–5.0 V,while the load current range is 0.05–2 A.The circuit can work in continuous conduction mode with constant frequency in high load current range.In addition,a stable output voltage can be obtained with small voltage ripple.In pace with the load current decreases to a critical value,the converter transforms into the discontinuous conduction mode smoothly.As the switching period increases,the switching loss decreases,which can significantly improve the conversion efficiency.The proposed AOT controlled valley current mode buck converter is integrated with standard 0.18μm process and the simulation results show that the converter provides well-loaded regulations with power efficiency over 95%.When the circuit switches between the two conduction modes drastically,the response time can be controlled within 30μs.The undershoot voltage is controlled within 25 mV under a large current hopping range.
基金Project (No.90707002) supported by the National Natural Science Foundation of China
文摘The boost type power supplies are widely used in portable consumer electronics to step up the input voltage to adapt for the high voltage applications like light-emitting diode(LED) driving and liquid crystal display(LCD) biasing.In these applications,a regulator with small volume,fewer external components and high efficiency is highly desired.This paper proposes a projected off-and on-time boost control scheme,based on which a monolithic IC with an on-chip VDMOS with 0.2 Ω on-state resistance RDS-ON was implemented in 1.5 μm bipolar-CMOS-DMOS(BCD) process.A 12 V,0.3 A boost regulator prototype is presented as well.With projected off-time and modulated on-time in continuous conduction mode(CCM),a quasi fixed frequency,which is preferred for ripple control,is realized.With projected on-time and modulated off-time in discontinuous conduction mode(DCM),pulse frequency modulation(PFM) operation,which is beneficial to light load efficiency improvement,is achieved without extra control circuitry.Measurement results show that an efficiency of 3% higher than that of a conventional method under 0.5 W output is achieved while a step load transient response comparable to that of current mode control is maintained as well.
文摘A current-mode buck DC-DC controller based on adaptive on-time （AOT） control is presented. The on-time is obtained by the techniques of input feedforward and output feedback, and the adaptive control is achieved by a sample-hold and time-ahead circuit. The AOT current-mode control scheme not only obtains excellent transient response speed, but also achieves the independence of loop stability on output capacitor ESR. In addition, the AOT current-mode control does not have subharmonic oscillation phenomenon seen in fixed frequency peak current-mode control, so there is no need of the slope compensation circuit. The auto-skip pulse frequency modulation （PFM） mode improves the conversion efficiency of light load effectively. The controller has been fabricated with UMC 0.6-μm BCD process successfully and the detailed experimental results are shown.
文摘A 1500 mA,10 MHz self-adaptive on-time （SOT） controlled buck DC-DC converter is presented. Both a low-cost ripple compensation scheme （RCS） and a self-adaptive on-time generator （SAOTG） are proposed to solve the system stability and frequency variation problem. Meanwhile a self-adaptive power transistor sizing （SAPTS） technique is used to optimize the efficiency especially with a heavy load. The circuit is implemented in a 2P4M 0.35μm CMOS process. A small external inductor of 0.47 μH and a capacitor of 4.7 μF are used to lower the cost of the converter and keep the output ripple to less than 10 mV. The measurement results show that the overshoot of the load transient response is 8 mV @ 200 mA step and the dynamic voltage scaling （DVS） performance is a rise of 16/zs/V and a fall of 20 μs/V. With a SAPTS technique and PFM control, the efficiency is maintained at more than 81% for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%.
文摘A 10 MHz ripple-based on-time controlled buck converter is presented. A novel low-cost dual ripple compensation, which consists of coupling capacitor compensation and passive equivalent series resistance compensation, is proposed to achieve a fast load transient response and robust stability simultaneously. Implemented in a 2P4M 0.35 um CMOS process, the converter achieves fix-frequency output with a ripple of below 10 mV and an overshoot of 10 mV at 400 mA step load transient response. With width optimization of the power transistors in an ultra-heavy load and PFM control in a light load, the efficiency stays at over 83% for a load range from 20 mA to 1.5 A and the peak efficiency reaches 90.16%.
文摘随着汽车智能化的发展,汽车内的电子控制单元(Electronic Control Unit,ECU)数量激增,因CAN总线自身的特点,挂载在总线上的ECU缺乏必要的安全保护。为此,提出了基于物理不可克隆函数(Physical Unclonable Functions,PUF)的车载网络ECU身份认证方案。该方案利用PUF的物理特征动态生成密钥,将身份认证划分为两个关联结合阶段,以满足车载网络实时性和安全性的双重需求。在车辆出厂前的非实时场景下,采用数字证书完成ECU间的注册。在车辆启动的实时场景下,基于认证链建立“一次一密”的快速身份认证机制。采用仿真测试对该方案的性能进行了评估,并与其他认证方案进行对比。实验结果表明,该方案可以同时满足车载网络在实时性和安全性方面的需求。
