共查询到20条相似文献,搜索用时 125 毫秒
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为满足辐射探测器前端读出电路对模拟电路稳压器片上集成和快速瞬态时间响应的需求,设计了一种基于0.18μm CMOS工艺的全片上集成LDO。采用大摆幅高增益放大器驱动输出功率管,增大了功率管栅极调节电压摆幅,减小了功率管尺寸和LDO压差电压。该放大器同时增大了LDO的环路增益和对功率管栅极的充放电电流,从而改善了瞬态响应性能。为了不牺牲环路增益带宽和芯片面积,并且保证LDO在整个负载电流区间内保持稳定,提出了一种负载电流分区频率补偿方法。仿真结果表明,在负载电容为200 nF,负载电流范围为0~200 mA时,设计的LDO相位裕度均大于53o。在相同功率管尺寸情况下,采用大摆幅高增益放大器可以将LDO最大输出电流能力提高到两倍以上。当负载电流从10 mA跳变到200 mA时,LDO输出电压恢复时间小于6.5μs。设计的LDO电路面积为120μm×264μm,满载时电源效率为97.76%,最小压差电压为50 mV。 相似文献
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以设计输出电流为700 mA,静态电流为50μA,芯片面积为1.5 mm×2.0 mm的LDO线性稳压器为目标,提出的LDO电路利用基准电路的输出直接作为芯片的输出,用基准电路所固有的跨导放大器对输出进行检测并反馈至单级放大器,放大后输出至功率管的基极,控制功率管输出额定的电压和电流。无需冗余的误差放大器,使得环路补偿极为简单,不存在传统LDO的补偿难题。在电路上把传统LDO电路所需各个模块的功能糅合到了一个较为简单的电路中,大大减小了芯片面积,并且减小了静态电流。对电路进行了仿真分析并采用2μm 36 V Bipolar工艺生产实现,流片后的测试结果表明该芯片实现了大电流,微功耗,小体积的特性。 相似文献
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本文设计了一款高效率,高输入电压,输出电流恒定的大功率白光LED驱动芯片。设计了芯片中的运算放大器电路、带隙基准电路、锯齿波发生器电路、比较器电路、误差放大器电路、输出过压保护电路、过热保护电路、功率管驱动电路、逻辑控制电路等,并给出了仿真结果。仿真结果表明设计的芯片达到了预期的要求。 相似文献
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V. R. H. Lorentz S. E. Berberich M. März A. J. Bauer H. Ryssel P. Poure F. Braun 《Analog Integrated Circuits and Signal Processing》2010,62(3):333-344
A novel average inductor current sensing circuit integrable in CMOS technologies is presented. It is designed for DC–DC converters
using buck, boost, or buck-boost topologies and operating in continuous conduction mode at high switching frequencies. The
average inductor current value is used by the DC–DC controllers to increase the light load power conversion efficiency (e.g.,
selection of the modulation mode, selection of the dynamic width of the transistors). It can also be used to perform the constant
current charging phase when charging lithium-ion batteries, or to simply detect overcurrent faults. The proposed average inductor
current sensing method is based on the lossless sensing MOSFET principle widely used in monolithic CMOS integrated DC–DC converters
for measuring the current flowing through the power switches. It consists of taking a sample of the current flowing through
the power switches at a specific point in time during each energizing and de-energizing cycle of the inductor. By controlling
precisely the point in time at which this sample is taken, the average inductor current value can be sensed directly. The
circuit simulations were done with the Cadence Spectre simulator. The improvements compared to the basic sensing MOSFET principle
are a lower power consumption because no high bandwidth amplifier is required, and less noise emission because the sensing
MOSFET is no more switched. Additionally, the novel average inductor current sensing circuit overcomes the low bandwidth limitation
previously associated with the sensing MOSFET principle, thus enabling it to be used in DC–DC converters operating at switching
frequencies up to 10 MHz and above. 相似文献
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一种BUCK型开关稳压器负载电流检测电路 总被引:3,自引:0,他引:3
针对Buck型开关稳压器的断续工作模式(DCM),基于CSMC0.5μm CMOS工艺设计实现了一种新颖的负载电流检测电路。同传统的电感电流采样方式不同,该结构直接应用与负载电流变化几乎同步的同步管栅极驱动信号作为"电流采样"信号,实现了负载平均电流的检测。经投片验证,提出的电流检测电路工作良好,且面积仅占芯片的1.5%,同传统采样方式相比,面积减小了21%,静态时的耗电仅为原来的40%。 相似文献
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Giovanni Busatto Roberto La Capruccia Francesco Iannuzzo Francesco Velardi Roberto Roncella 《Microelectronics Reliability》2003,43(4):577-583
A new on-chip non-invasive integrated current sensing, compatible with standard CMOS technology, has been developed, using a 1.2 μm BiCMOS ALCATEL technology, to sense the current in the drain side of a power MOSFET. The circuit is based on a split-drain magnetic sensor, implemented on the same chip of an integrated gate driver for a power MOSFET. A CMOS biasing circuit with a differential current output is also developed. The simulation results of the current sensing show a conversion gain of 1.25 mV/mT. 相似文献
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Yang Zhang Zane R. Prodic A. Erickson R. Maksimovic D. 《Power Electronics Letters, IEEE》2004,2(3):100-103
An approach for online current sensing calibration is presented where an auxiliary switch and a precision sense resistor are connected in parallel with a main power switch to achieve accuracy comparable to the sense resistor method, together with the advantage of essentially no additional power loss. The proposed current-sensing circuit and the calibration methods are particularly well suited for digital controller implementations where the required control and calibration functions can be easily accomplished. Experimental results with a digitally controlled 1.5-V 15-A synchronous buck converter demonstrate functionality of the online calibration approach, showing a significant improvement in accuracy over voltage sensing across the power MOSFET on-resistance. 相似文献
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为磁滞电流控制的DC-DC开关稳压器设计了一种新型的极限电流检测器。该电路不借助于专门的电流检测电路,只使用一个检测MOSFET和一个电压比较器来实现极限电流检测,减小了电路的复杂度。针对电流检测器的要求,设计了一种低电源电压、高共模电压的比较器。使用TSMC 0.18μm CMOS混合信号工艺,对电路进行设计。结果表明,电路具有很好的容差特性,并且电路可工作在1.2 V的低电源电压下。 相似文献
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灵巧功率集成电路中功率MOSFET电流感知方法的研究 总被引:1,自引:0,他引:1
功率器件的过流保护是提高灵巧功率集成电路可靠性的关键,采用不同的电流检测方法会有不同的误差。通过对功率MOSFET的电流检测技术的研究,对比分析了几种常用的电流感知方法,重点阐述了应用在灵巧功率集成电路中感知高压功率器件电流的SenseFET结构的工作原理,并分析了影响电流检测准确度的误差源。可以为设计高性能的电流检测过程提供参考。 相似文献
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电流采样电路作为电流控制的DC/DC变换器重要组成部件之一,其精度和响应速度已受到越来越高的重视.提出的电流采样电路没有使用运算放大器,简化了电路结构,降低了功耗.同时,电路中引入的补偿电流进一步提高了采样的精度.基于0.5μm CMOS工艺实现该电路,HSPICE模拟仿真结果表明该电路具有较高的采样精度,最高可达99.9%,且在负载、输入电压、温度变化时,采样精度波动很小. 相似文献
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An LED driving circuit in accurate proportional current sampling mode is designed and fabricated based on CSMC 0.5 μm standard CMOS technology. It realizes accurate sensing of sampling current variation with output driving current. A better constant output current characteristic is achieved by using an amplifier to clamp the drain voltage of both the sampling MOSFET and power MOSFET to the same value with feedback control. Small signal equivalent circuit analysis shows that the small signal output resistance in the accurate proportional current sampling mode circuit is much larger than that in a traditional proportional current sampling mode circuit, and circuit stability could be assured. Circuit simulation and chip testing results show that when the LED driving current is 350 mA and the power supply is 6 V with ±10% variation, the stability of the output constant current of the accurate proportional current sampling mode LED driving 1C will show 41% improvement over that of a traditional proportional current sampling mode LED driving IC. 相似文献