输入电压

Meanwhile, this detected voltage difference is amplified and filtered, and finally the processed signal is transmitted to the analog input of the DAQ card for further software operation, display, and storage.

其工作原理是利用DAQ卡类比输出通道，送出不同频率且幅值恒定的正弦电压信号，透过修正型Howland定电流驱动电路将电压信号转成电流信号加入体内，由量测电极取出电压信号经放大滤波后，把讯号送入类比输入DAQ卡，并在LabVIEW人机介面上做运算处理、分析、显示与储存。

Voltage of 555IC fanout or assistant fanout feeding back to input for voltage apron string,forms deferent DS feedback,and holds threshold voltage inside two comparators to float along with.

把555IC输出端或辅助输出端的电压反馈到电压控制输入端，形成输出的数字信号反馈，使内部2个比较器的阈值电压随之浮动。

This high voltage electrostatic precipitation controller has 7 channels of analog input,2 channels of analog output, 12 digital inputs and 16 digital outputs. The analog input includes primary current, secondary current, primary voltage, secondary voltage, etc. Controller uses MAX 187 as the A/D converter, which ensure the sampling speed and the conversion precision in the same time. The processor unit is RCM2250 module. Rabit 2000 processor, a 128K SRAM and a 256K Flash Rom are integrated in RCM2250, which improves the performance of pricipitation controller. MAX504 is used to produce the 4~20mA current output.

模拟量输入采集的信号有升压变压器一次电流、一次电压、二次电流、二次电压等，采用12位逐次比较式A/D转换器MAX187，兼顾采样速率和转换精度；中央处理单元采用以8位嵌入式处理器Rabbit2000为基础的RCM2250模块，外扩128KSRAM和256K Flash ROM，内部资源丰富，提高了控制器的整体性能；模拟量输出采用内带基准源的10位电压输出数模转换器MAX504，实现了标准4～20mA电流信号输出；控制器通过控制算法在相应开关量点上输出可控硅的触发脉冲。

A digital AGC circuit using a digital potentiometer to rep lace the feedback resistance of the amp lifierwas designed. In order to get an app rop riate gain, MCU adjusted the resistance of the digital potentiometer automatically according to the voltage value of amp lifierps output.

为使输入信号不受这一限制，设计了一种数字式自动增益放大电路，该电路采用数字电位器取代放大器的反馈电阻，单片机根据放大器输出电压自动调整数字电位器的阻值来调节放大器增益，使输出电压始终维持在所设定的上下限电压之间。

Switching Power Supply with the traditional distinction between :(1) not only the output voltage feedback, feedback from the average input current;(2) Current benchmarks signal voltage error signal and full-wave rectifier voltage signal sampling the product.

与传统开关电源的区别是：不仅反馈输出电压，还反馈输入平均电流；(2)电流环基准信号为电压环误差信号与全波整流电压取样信号之乘积。

2TheMax GPX750 PSU for the desktop computer features total output of 750W, rated supply voltage of 115V to 230V auto range, rated mains frequency of 47 to 63 Hz, rated input of 115V at 10A or 230V at 5A, efficiency of 85% minimum at typical load, holdup time of 16.6ms at nominal line under full load condition, power good signal between 100ms to 500ms, over current protection at 110% to 150% individual output power, over voltage protection for +5V is between 5.8V to 6.3V,+12V from 14V to 17V, 3.3V from 3.6V to 4.2V, air flow by DC fan, operating temperature of 0°C to 50°C and operating humidity of 20% to 90% non-condensing.

2themax gpx750电源为桌上型电脑的功能总产量750瓦特，额定电源电压115v到230v汽车范围，额定工频47至63赫兹，额定输入的115v在10 A条或230v在5 ，效率85 ％，最低在典型负载，持的时间16.6ms的名义在网上下，满负荷条件下，电源良好信号之间的100 ms到500ms ，过电流保护在110 ％至150 ％个别的输出功率，过电压保护，为5 V是之间的5.8 V至6.3v ，+12 V的从14v至17v ，电压为3.3 V从V到3.6 V至4.2 V ，空气流量由直流风扇，操作温度0° C到50 ° C和运作中的湿度为20 ％至90 ％，非冷凝。

When the amplifier output is in either the positive or negative saturated state, the positive feedback network provides a voltage at the non-inverting input which is determined by the attenuation of the feedback loop and the saturation voltage of the amplifier.

不论放大器输出是正是负，只要OP达到输出饱和状态，OP正反馈路径就会在OP同相输入端加上一个电压，该电压的大小由OP正反馈路径的衰减和OP输出饱和时的电压共同决定。

precise calculating formula is derivated to determine magnification ratio of voltage,input resistance and output resistance in amplifying circuits based on th feedback circuit model with cascade voltage.with th new calculating methods put forward by the author,it is possible to solve the problems in terms of calculation in amplifying circuits,the key problem being low level of exactness.the research shows the influence of components′ parameters of basic amplifying circuits and feedback circuits on feedback amplifying circuits.the results of the research may contribute to design amplifying circuits and electronic instrument with higher performance,due to the simpler calculation in the design of feedback circuit with cascade voltage.

摘 要：在建立电压串联反馈电路模型基础上，推导出放大电路中的电压放大倍数、输入电阻、输出电阻的精确计算公式。提出新的计算方法，从而解决了放大电路计算不方便，精确度不高、准确性不够的问题。同时进一步揭示了基本放大电路、反馈电路元件参数对反馈放大电路的影响关系。为设计出高性能放大电路及电子设备指明了方向，更加方便于电压串联反馈电路的计算。

In order to realize real-time control, the paper studied two kinds of closed-loop control structures such as based on scalar quantity and double closed-loop control structure, moreover established their control structure, then simulation to the double closed-loop control structure of voltage source type matrix converter. The simulation results indicate that reach the real-time control requests, the system dynamic response performance is good, the converter input output can be adjusted in the short time.

为实现电压源型阵变换器的实时控制要求，论文对基于标量控制和双闭环的两种电压源型矩阵变换器闭环控制结构进行了研究，分别建立了这两种闭环控制的控制结构，并且对电压源型矩阵变换器的双闭环控制结构进行仿真，仿真结果表明达到了实时控制的要求，系统的动态响应性能好，变换器的输入输出能在较短的时间内达到调节。

One disadvantage of this method of stabilization is the additional output noise and offset voltage caused by increased amplification of input-referred voltage noise and input offset voltage.

这种稳定方法的一个不足是：输入端的有关电压噪声和失调电压增大会额外地增加输出噪声和失调电压。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。