科技英语 低通滤波器 原文与翻译.docVIP

Words and Expressions integrator n. 积分器 amplitude n. 幅值 slope n 斜率 denominator n. 分母 impedance n 阻抗 inductor n. 电感 capacitor n 电容 cascade n. 串联 passband n 通带 ringing n. 振铃 damping n. 阻尼，衰减 conjugate adj. 共轭的 stage v. 成为 low-pass filters 低通滤波器 building block 模块 linear ramp 线性斜坡 log/log coordinates 对数/对数坐标 Bode plot 伯德图 transfer function 传递函数 complex-frequency variable 复变量 complex frequency plane 复平面 real component 实部 frequency response 频率响应 complex function 复变函数 Laplace transform 拉普拉斯变换 real part 实部 imaginary part 虚部 angular frequency 角频率 frequency response 频率响应 transient response 瞬态响应 decaying-exponential response 衰减指数响应 step function input 阶跃（函数）输入 time constant 时间常数 first-order filters 一阶滤波器 second-order low-pass filters 二阶低通滤波器 passive circuit 无源电路 active circuit 有源电路 characteristic frequency 特征频率 quality factor n. 品质因子，品质因数 circular path 圆弧路径 complex conjugate pairs 共轭复数对 switched-capacitor 开关电容 negative-real half of the complex plane 复平面负半平面 Unit 4 Low-pass Filters First-Order Filters An integrator (Figure 2. la) is the simplest filter mathematically, and it forms the building block for most modern integrated filters. Consider what we know intuitively about an integrator. If you apply a DC signal at the input (i.e., zero frequency), the output will describe a linear ramp that grows in amplitude until limited by the power supplies. Ignoring that limitation, the response of an integrator at zero frequency is infinite, which means that it has a pole at zero frequency. (A pole exists at any frequency for which the transfer functions value becomes infinite.)（为什么为极点，为什么低通？） Figure 2.la A simple RC integrator We also know that the integrators gain diminishes with increasing frequency and that at high frequencies the output voltage beco