RC电路的过渡过程.doc

Experiment 4 Transient Process of RC CircuitI Objectives1. To Learn to use oscilloscope.2. To study the square wave responses of first-order circuits.II Apparatus and EquipmentsNameSpec.Number1Two-channel oscilloscopeXJ432812Function generatorEE1641D13ElementsR=510, 1 k, 2 k, 3 k, 10 kC=0.1f, 0.3f, 0.4f, 1f,3 f, 10f1III Preperations1. The rectangular pulse responses of a RC circuitFig.4-1 and Fig.4-2 are the rectangular pulses and a RC circuit respectively.Fig.4-1 Rectangular pulses Fig.4-2 RC circuitSupply the signal of rectangular pulses to the RC circuit, we get the responses shown in Fig.4-3 if the initial value of uC is zero. Obviously, RC circuit charges and discharges continuously. Its the essence of pulse responses of RC circuit.2. Applications of a RC circuit(1) Differential circuit in Fig.4-4when the parameters R and C make the time constant tp, we can get the response uC shown in Fig.4-7. The output voltage uC is approximately the integration of the input voltage ui.Fig.4-3Fig.4-4 RC differential circuit Fig.4-5 Response of the circuit Fig.4-4Fig.4-6 RC integral circuit Fig.4-7 Response of the circuit Fig.4-6IV Lab Work1. Measure the peak values and periods of sinusoids produced by a function generator.2. Measure the magnitude, periods, and pulse width of square waves produced by a function generator.3. Measure the phase difference of two sinusoids.Supply the sinusoid ui (f=1kHz, Up-p=1V) to the circuit Fig.4-4, observe the voltage ui and uR with oscilloscope, measure the phase difference of them, and compare the magnitudes of them. The parameters are listed as follow:(1) R=1k, C=0.1f;(2) R=1k, C=0.2f;(3) R=2k, C=0.1f;(4) R=1k, C=10f.4. Study the transient process of a RC circuitSupply a square-wave signal (amplitude 4V, periods 4ms, and pulse width tw about 4ms) to the circuit Fig.4-6.(1) Observe the waveforms of uR, uC, and ui in the case=RC;(4) Observe the waveforms of ui, uC, and uR simultaneously in the case=RC;V Preparations1. Reading and understanding the specification of two-channel oscilloscope XJ4328;2. Preparing the circuit parameters for lab work 4.VI Discussions1. Give the data measured and draw the waveforms observed;2. Analyze the effects of the circuit parameters on the square-wave responses in first-order circuits.实验四 RC电路的过渡过程一、实验目的1学习使用XJ4328示波器显示波形和测量幅度、频率、相位的方法。2研究一阶电路的方波响应。二、实验仪器设备名 称规格，型号数量1二踪示波器XJ43281台2函数发生器EE1641D型1台3实验元件R=510, 1 k, 2 k, 3 k, 10 kC=0.1f, 0.3f, 0.4f, 1f,3 f, 10f1块三、实验原理RC串联电路是电子线路中经常用到的线路，对一个工程技术人员，熟悉它的性能是必要的。1RC电路的矩形脉冲响应矩形脉冲序列波形如图4-1所示。图4-1 矩阵脉冲序列波形图 图4-2 RC串联电路图若将此矩形脉冲序列信号加在电容电压的初始值uC（0）=0的RC电路上，如图4-2所示，其响应曲线如图4-3所示。显然，电路的脉冲响应实质是RC电路不断充放电的过程。2RC电路的应用(1) RC微分电路如图4-4所示的电路，选择适当的电路参数，使电路的时间常数tp时条件下，电路的输出电压近似地正比于输入电压对时间的积分。输入电压为矩形脉冲时，输出电压波形为三角波，如图4-7所示。uc 图4-6 RC积分电路 图4-7 RC积分电路的输入输出电压波形四、实验任务1利用示波器测量函数发生器输出正弦波的幅值和周期（自己调节）。2利用示波器测量函数发生器输出方波的幅值、周期和脉冲宽度。3利用示波器测量相位差。按图4-4接线，AB间接函数发生器输出的正弦信号取f=1kHz, Up-p=1V。在示波器屏幕上同时观察ui和uR的波形，测量两个电压的相位差，并注意比较两个电压的幅值大小。电路参数分别为：(1) R=1 k, C=0.1f;(2) R=1 k, C=0.2f;(3) R=2 k, C=0.1f;(4) R=1 k, C=10f。4利用示波器研究RC电路的过渡过程按图4-6接线，AB间接函数信号发生器输出的方波信号，方波幅值为4伏，周期为4毫秒，脉冲宽度tw约为2毫