如图，当V_A=V_B=3V时，则V_Z=（）。<img src='https://img2.soutiyun.com/shangxueba/ask/18498001-18501000/18498701/201506251432481886.jpg' />

A、<img src='https://img2.soutiyun.com/ask/2020-09-25/969911167510288.png' /> B、<img src='https://img2.soutiyun.com/ask/2020-09-25/969911174565691.png' /> C、<img src='https://img2.soutiyun.com/ask/2020-09-25/969911180562034.png' /> D、<img src='https://img2.soutiyun.com/ask/2020-09-25/969911186626381.png' />

<img src='https://img2.soutiyun.com/ask/2021-01-21/980090366712026.jpg' />

A．3 B．-3 C．0.7 D．2.3

(1)设计一同相放大电路,如图题2.3.3a所示其闭环增益A_i=10,当v_i=0.8V时,流过每一电阻的电流小于100uA,求R₁和R₂的最小值;(2)设计一反相放大电路,如图2.3.3b所示,要求电压增益AP=v₀/v_i=-8,当输入电压v_i=-1V时,流过R₁和R₂的电流小于20μA,求R₁和R₂的最小值。 <img src='https://img2.soutiyun.com/ask/2020-12-25/977735122191139.png' />

电路如图题4-6(a)所示，u_S=12V、R=2kΩ，网络N的VCR如图题4-6(b)所示，求u和i，并求流过两线性电阻的电流。 <img src='https://img2.soutiyun.com/ask/2020-08-27/967409762293118.png' />

555定时器芯片接成的电路如图6-26(a)所示。试回答: (1)该电路的名称是什么？ (2)若+V_OC=+10V,R=10kΩ,C=300pF,计算其暂态脉冲宽度tPO. (3)给定输入u1的波形如图6-26(b)所示，已知低电平时长为10μs,试画出电容电压u_C的波形和对应的输出u_O的波形。注意此时输入u₁的低电平时长大于其暂态脉冲宽度。 (4)如果在图6-26(a)所示的555定时器芯片的5脚外接一个+5V的电压源，问暂 态脉冲宽度是增加、减少还是不变？为什么？ <img src='https://img2.soutiyun.com/ask/2020-09-06/968244942565249.png' />

A．12 B． 1.2 C． -1.7 D． 1.7

若激励信号e(t)为如图4-45(a)所示周期矩形脉冲,e(t)施加于图4-45(b)所示电路,研究响应v₀(t)之特点.已求得v₀(t)由瞬态响应<img src='https://img2.soutiyun.com/ask/2020-12-01/975676035825158.png' />和稳态响应<img src='https://img2.soutiyun.com/ask/2020-12-01/975676035825158.png' />两部分组成,其表达式分别为: <img src='https://img2.soutiyun.com/ask/2020-12-01/975676076102462.png' /> 其中<img src='https://img2.soutiyun.com/ask/2020-12-01/975676096774644.png' />为<img src='https://img2.soutiyun.com/ask/2020-12-01/975676116769788.png' />第一周期的信号 <img src='https://img2.soutiyun.com/ask/2020-12-01/975676131898653.png' /> (1)画出v₀(t)波形,从物理概念讨论波形特点; (2)试用拉氏变换方法求出上述结果; (3)系统函数极点分布和激励信号极点分布对响应结果特点有何影响. <img src='https://img2.soutiyun.com/ask/2020-12-01/97567614898663.png' />

电路如图题10.8.10所示，设A₁，A₂均为理想运放，电容C上的初始电压v_c(0)=0V。若v₁为0.11V的阶跃信号，求信号加上后一秒钟，v₀₁、v₀₂，v₀₃所达到的数值。 <img src='https://img2.soutiyun.com/ask/2020-12-02/975778334256464.png' />

电路如图题11.1.3所示，已知V₂=20V，R_L=50千欧，C=1000μ_F。(1)如当电路中电容C开路或短路时，电路会产生什么后果？两种情况下V_L各等于多少？(2)当输出电V_L=28V，18V，24V和9V时，试分析诸情况下，哪些属于正常工作的输出电压，哪些属于故障情况，并指出故障原因。 <img src='https://img2.soutiyun.com/ask/2020-12-04/975948536131091.png' />

<img src='https://img2.soutiyun.com/ask/2020-11-17/974475215782968.png' />

<img src='https://img2.soutiyun.com/ask/2020-11-17/974475827409951.png' />

二极管电路如图题3.4.8a所示，设输入电压v_1(t)波形如图b所示，在0~5ms的时间间隔内，试绘出v_o(t)的波形，设二极管是理想的。 <img src='https://img2.soutiyun.com/ask/2020-11-26/975255598674505.png' />

BJT的输出特性如图题5.3.1所示。求该器件的β值;当i_C=10mA和i_C=20mA时，管子的饱和压降V_CES为多少？ <img src='https://img2.soutiyun.com/ask/2020-11-26/975258581596118.png' />

<img src='https://img2.soutiyun.com/ask/2021-03-03/98363452931372.png' />

<img src='https://img2.soutiyun.com/ask/2020-12-25/977735539297996.png' />

<img src='https://img2.soutiyun.com/ask/2020-10-14/971545303208146.jpg' />

A．0、4、2、3 B．0、4、3、3 C．0、5、3、3 D．0、5、3、4

<img src='https://img2.soutiyun.com/ask/2020-11-16/97440849814341.png' />

<img src='https://img2.soutiyun.com/ask/2020-11-17/974474321260804.png' />

<img src='https://img2.soutiyun.com/ask/2020-09-17/96918661355307.png' />

A.<img src='https://img2.soutiyun.com/ask/2020-10-16/971713879637275.png' /> B.<img src='https://img2.soutiyun.com/ask/2020-10-16/971713887889689.png' /> C.<img src='https://img2.soutiyun.com/ask/2020-10-16/971713895330902.png' />

<img src='https://img2.soutiyun.com/ask/2020-11-26/975260755556462.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/50850001-50853000/50851898/967907462814711.png' />