质子交换膜燃料电池是一个封闭的发电装置,其运行性能仅能通过单片电池电压进行反应.根据单片电池电压的暂态变化,可以调整控制策略、工作条件,使电堆运行在最佳状态,延长其使用寿命.为满足燃料电池暂态分析及故障诊断的需要,拟利用高...质子交换膜燃料电池是一个封闭的发电装置,其运行性能仅能通过单片电池电压进行反应.根据单片电池电压的暂态变化,可以调整控制策略、工作条件,使电堆运行在最佳状态,延长其使用寿命.为满足燃料电池暂态分析及故障诊断的需要,拟利用高速数据采集卡,结合电阻分压及高速模拟切换开关,构建一种高速单片电池电压监测系统,实现燃料电池单片电压的高速、高精度采集.经试验测试表明,设计的监测系统测量速度、测量精度均比现有单片电压采集系统高,平均误差为4. 52 m V,测量时间小于6 ms.展开更多
A DC regulated power supply with numerical control based on single chip microcomputer （SCM） is designed. SCM is the main controller and output voltage o{ DC power supply can be set by keyboard. The analog voltage ca...A DC regulated power supply with numerical control based on single chip microcomputer （SCM） is designed. SCM is the main controller and output voltage o{ DC power supply can be set by keyboard. The analog voltage can be obtained through D/A converter （DAC0832） so that different voltages can be provided by operational amplifier. The output voltage varies from 0 V to 12 V with the incremental value of 0. 1 V. The actual output voltage is shown in the nixietube. This DC regulated power supply is characterized by simple structure and easy operation.展开更多
A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump...A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.展开更多
the system to DC voltage source as the core, AT89C52 MCU as the main controller, the output voltage to set the DC power supply through the keyboard, with a step function voltage to reality, the actual output value. Th...the system to DC voltage source as the core, AT89C52 MCU as the main controller, the output voltage to set the DC power supply through the keyboard, with a step function voltage to reality, the actual output value. This design is divided into four modules： SCM control and display module, digital to analog （D/A） conversion module, a constant voltage source module, output module. MCU control module as the core, the input signal is converted to digital quantity output; constant current source module voltage D/A conversion to analog conversion into constant pressure through a constant voltage circuit. The system has good reliability, high precision.展开更多
A monolithic clock-recovery circuit used in 622 Mb/s optical communication system is designed,which is based on the phase-locked loop theory,and uses bipolar transistor model.It overcomes the shortcoming of clock reco...A monolithic clock-recovery circuit used in 622 Mb/s optical communication system is designed,which is based on the phase-locked loop theory,and uses bipolar transistor model.It overcomes the shortcoming of clock recovery method based on filter,and implements monolithic clock-recovery IC.The designed circuits include phase detector,voltage-controlled oscillator and loop filter.Among them,the voltage-control oscillator is a modified two-stage ring oscillator,which provides quadrature clock signals and presents wide voltage-controlled range and high voltage-controlling sensitivity.展开更多
文摘质子交换膜燃料电池是一个封闭的发电装置,其运行性能仅能通过单片电池电压进行反应.根据单片电池电压的暂态变化,可以调整控制策略、工作条件,使电堆运行在最佳状态,延长其使用寿命.为满足燃料电池暂态分析及故障诊断的需要,拟利用高速数据采集卡,结合电阻分压及高速模拟切换开关,构建一种高速单片电池电压监测系统,实现燃料电池单片电压的高速、高精度采集.经试验测试表明,设计的监测系统测量速度、测量精度均比现有单片电压采集系统高,平均误差为4. 52 m V,测量时间小于6 ms.
文摘A DC regulated power supply with numerical control based on single chip microcomputer （SCM） is designed. SCM is the main controller and output voltage o{ DC power supply can be set by keyboard. The analog voltage can be obtained through D/A converter （DAC0832） so that different voltages can be provided by operational amplifier. The output voltage varies from 0 V to 12 V with the incremental value of 0. 1 V. The actual output voltage is shown in the nixietube. This DC regulated power supply is characterized by simple structure and easy operation.
文摘A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.
文摘the system to DC voltage source as the core, AT89C52 MCU as the main controller, the output voltage to set the DC power supply through the keyboard, with a step function voltage to reality, the actual output value. This design is divided into four modules： SCM control and display module, digital to analog （D/A） conversion module, a constant voltage source module, output module. MCU control module as the core, the input signal is converted to digital quantity output; constant current source module voltage D/A conversion to analog conversion into constant pressure through a constant voltage circuit. The system has good reliability, high precision.
文摘A monolithic clock-recovery circuit used in 622 Mb/s optical communication system is designed,which is based on the phase-locked loop theory,and uses bipolar transistor model.It overcomes the shortcoming of clock recovery method based on filter,and implements monolithic clock-recovery IC.The designed circuits include phase detector,voltage-controlled oscillator and loop filter.Among them,the voltage-control oscillator is a modified two-stage ring oscillator,which provides quadrature clock signals and presents wide voltage-controlled range and high voltage-controlling sensitivity.
