电子信息专业英语答案中英文对应.docVIP

Unit 1 电子学：模拟和数字 Unit 1-1 第一部分：理想运算放大器和实际限制 The approach to such a situation is to be methodical, and take the necessary time to read and understand each definition in the order that it is listed. Without a real appreciation of what each means, the designer is doomed to failure. The objective is to be able to design a circuit from the basis of the published data, and know that it will function as predicted when the prototype is constructed. In order to discuss the ideal parameters of operational amplifiers, we must first define the terms, and then go on to describe what we regard as the ideal values for those terms. At first sight, the specification sheet for an operational amplifier seems to list a large number of values, some in strange units, some interrelated, and often confusing to those unfamiliar with the subject. It is all too easy with linear circuits, which appear relatively simple when compared with today’s complex logic arrangements, to ignore detailed performance parameters which can drastically reduce the expected performance.2 为了讨论运算放大器的理想参数，我们必须首先定义一些指标项，然后对这些指标项讲述我们所认为的理想值。第一眼看运算放大器的性能指标表，感觉好像列出了大量的数值，有些是陌生的单位，有些是相关的，经常使那些对运放不熟悉的人感到迷惑。对于这种情况我们的方法是花上必要的时间有系统的按照列出的次序阅读并理解每一个定义。如果没有对每一项性能指标有一个真正的评价，设计人员必将失败。目标是能够依据公布的数据设计电路，并确认构建的样机将具有预计的功能。对于线性电路而言，它们与现在的复杂逻辑电路结构相比看起来较为简单，（因而在设计中）太容易忽视具体的性能参数了，而这些参数可极大地削弱预期性能。 Let us take a very simple but striking example. Consider a requirement for an amplifier having a voltage gain of 10 at 50 kHz driving into a 10 kW load.3 A common low-cost, internally frequency-compensated op amp is chosen; it has the required bandwidth at a closed-loop gain of 10, and it would seem to meet the bill.4 The device is connected, and it is found to have the correct gain. But it will only produce a few volts output swing when the data clearly shows that the output should be capable of driving to within two or three volts of the supply rails.5 The designer has forgotten that the maximum output voltage swing is severely limited by fre