Unit 3 Circuit Analysis Using the Ideal Operational Amplifier ear Background n Words and expressions ÷ Text and notes L: Grammar Exercises Reading material 上海海事大学息工程学院
上海海事大学信息工程学院 Unit 3 Circuit Analysis Using the Ideal Operational Amplifier Background Words and expressions Text and notes Grammar Exercises Reading material
Background a An amplifier, electronic amplifier or(informally) amp is an electronic device that increases the power of a signal a It does this by taking energy from a power supply and controlling the output to match the input signal shape but with a larger amplitude. In this sense, an amplifier modulates the output of the power supply to make the output signal stronger than the input signal. An amplifier is effectively the opposite of an attenuator: while an amplifier provides gain, an attenuator provides loss 上海海事大学息工程学院
上海海事大学信息工程学院 Background ◼ An amplifier, electronic amplifier or (informally) amp is an electronic device that increases the power of a signal. ◼ It does this by taking energy from a power supply and controlling the output to match the input signal shape but with a larger amplitude. In this sense, an amplifier modulates the output of the power supply to make the output signal stronger than the input signal. An amplifier is effectively the opposite of an attenuator: while an amplifier provides gain, an attenuator provides loss
Background a The types of amplifiers can be categorized in different ways. One is by the frequency of the electronic signal being amplified; audio amplifiers amplify signals in the audio(sound)range of less than 20 kHz, RF amplifiers amplify frequencies in the radio frequency range between 20 khz and 300 GHz. another is which quantity, voltage or current is being amplified; amplifiers can be divided into voltage amplifiers, current amplifiers transconductance (i=)amplifiers, and transresistance amplifiers. a further distinction is whether the output is a linear or nonlinear representation of the input. Amplifiers can also be categorized by their physical placement in the signal chain(信号通路,信号链) 上海海事大学息工程学院
上海海事大学信息工程学院 Background ◼ The types of amplifiers can be categorized in different ways. One is by the frequency of the electronic signal being amplified; audio amplifiers amplify signals in the audio (sound) range of less than 20 kHz, RF amplifiers amplify frequencies in the radio frequency range between 20 kHz and 300 GHz. Another is which quantity, voltage or current is being amplified; amplifiers can be divided into voltage amplifiers, current amplifiers, transconductance(跨导) amplifiers, and transresistance amplifiers. A further distinction is whether the output is a linear or nonlinear representation of the input. Amplifiers can also be categorized by their physical placement in the signal chain（信号通路，信号链）
741 a The first practical electronic device which could amplify was the audion( ( triode,三极管) vacuum tube, invented in 1906 by Lee De Forest, which led to the first amplifiers. The terms"amplifier"and " amplification"(from the Latin amplificare, to enlarge or expand)were first used for this new capability around 1915 when triodes became widespread. 2 For the next 50 years vacuum tubes were the only devices which could amplify, and were used in all amplifiers until the 1960s wher transistors began to be used. Most amplifiers today use transistors although tubes are still used 上海海事大学息工程学院
◼ The first practical electronic device which could amplify was the Audion (triode，三极管) vacuum tube, invented in 1906 by Lee De Forest, which led to the first amplifiers. The terms "amplifier" and "amplification" (from the Latin amplificare, 'to enlarge or expand') were first used for this new capability around 1915 when triodes became widespread.[2] For the next 50 years vacuum tubes were the only devices which could amplify, and were used in all amplifiers until the 1960s, when transistors began to be used. Most amplifiers today use transistors, although tubes are still used. 上海海事大学信息工程学院
Words and expressions FH-eg Buffer n.缓冲器 By-product n.副产品,出乎意料的结果 a Circuitry n.电路,线路 ■ Formula n.公式,规则 ■Fu|crum n.杠杆的支点 Ground V.使接地;n.接地,地线 Impedance n.阻抗 ■| infinitesimal adv.无穷小,极小,无限小 ■| nherent adj.固有的,内在的,与生俱来的 ■| intuitive adj.直觉的 ■| nvestigate V.调查,研究 Latch 闭锁(n.锁存器) Lever n.杆,杠杆 Mythica adj.神话的,虚构的 ■ Offset n.偏移量,抵消 上海海事大学息工程学院
上海海事大学信息工程学院 Words and expressions ◼ Buffer n. 缓冲器 ◼ By-product n. 副产品，出乎意料的结果 ◼ Circuitry n. 电路，线路 ◼ Formula n. 公式，规则 ◼ Fulcrum n. 杠杆的支点 ◼ Ground v. 使接地；n. 接地，地线 ◼ Impedance n. 阻抗 ◼ Infinitesimal adv. 无穷小，极小，无限小 ◼ Inherent adj. 固有的，内在的，与生俱来的 ◼ Intuitive adj. 直觉的 ◼ Investigate v. 调查，研究 ◼ Latch v. 闭锁 (n. 锁存器) ◼ Lever n. 杆，杠杆 ◼ Mythical adj. 神话的，虚构的 ◼ Offset n. 偏移量，抵消