电子信息类专业英语,http:/www.cmpbook.com,机械工业出版社同名教材配套电子教案,温丹丽 高源 制作,Passage One Digital Circuits,机械工业出版社 http:/www.cmpbook.com,1How can a digital electric system perform the task? 2What is a bit?,Passage One Digital Circuits,Words and Expressions discrete 5: a. 不连续的，离散的 quartz kwC:ts n. 石英 binary 5bainEri a. 二进位的 bit bit n. 计位，比特 relay 5ri:lei n. 电工继电器 vacuum 5vAkjuEm a. 真空的 resistor ri5zistE n. 电电阻器 capacitor kE5pAsitE n. 电容器 package 5pAkidV n. 包裹，包 dimension di5menFEn n. 尺寸，尺度,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,dissipation 7disi5peiFEn n. 消散，分散 instrumentation 7instrumen5teiFEn n. 使用仪器 synthesis 5sinWisis n. 综合，合成 proportional prE5pC:FEnl a. 成比例的 transmit trAnz5mit v. 传输，转送 immune i5:n a. 免疫的 interference 7intE5fiErEns n. 冲突，干涉 ample 5Ampl a. 充足的，丰富的 modification 7mCdifi5keiFEn n. 更改，修改，修正 pulse pQls n. 脉搏，脉冲 inadequate in5Adikwit a. 不充分的，不适当的 digital communication 数字通信系统,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,Text An electronic system is an orderly collection of interacting electronic building blocks that performs a desired task. A digital electronic system performs the tasks by dealing with discrete quantities. Discrete quantities are integral, fractional, or mixed numbers that represent, to the nearest least significant digit, some quantities in the real world such as temperature, pressure, or distance. In contrast there are analog electronic systems that represent these quantities on a continuous scale.,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,Many measurements may be represented in either digital or analog form. For example, time has been represented over the centuries in an analog form the angle subtended by the small and large hands of the clock provided all the information about time that was desired. For better resolution in time, a second hand was added. In the last several years a totally new method was developed to measure and display time. The method is based on the oscillation frequency of a quartz crystal that in conjunction with digital circuitry and digital display technology presents the time information in digital form as a number.,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,Many measurements may be represented in either digital or analog form. For example, time has been represented over the centuries in an analog form the angle subtended by the small and large hands of the clock provided all the information about time that was desired. For better resolution in time, a second hand was added. In the last several years a totally new method was developed to measure and display time. The method is based on the oscillation frequency of a quartz crystal that in conjunction with digital circuitry and digital display technology presents the time information in digital form as a number.,Passage One Digital Circuits,Digital processing of information has indeed become widespread in this decade；in addition to digital watches, clocks, and calculators, there are numerous digital controllers (microcomputers) used in home appliances and automobiles. In digital electronic systems, information is represented by binary digits, bits. A bit may assume either one of two values: 0 or 1. A mathematical system that uses only two digits is called a binary system. Its foundations were laid by the British Mathematician George Boole (18151864) in his classic treatise An Investigation of the Laws of Thought (1854).,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,The invention of the transistor may be viewed as another major breakthrough in digital information processing. The volume occupied by a transistor is about one hundredth of that occupied by either a relay or a vacuum tube, and a similar ratio holds for the power dissipated by the devices under comparison. The transistor also provide the technological base for the development of integrated circuits, an ensemble of many transistor that are interconnected to perform a specified function.,机械工业出版社 http:/www.cmpbook.com,Passage One Digital Circuits,The first integrated circuit was developed in 1958, which is a start of a revolutionary change in the art of electronics design. In the initial stages of semiconductor technology development, the devices were classified as either discrete or integrated. A digital integrated circuit consisted of several transistors and sometimes also of passive components (resistors and capacitors) on a semiconductor substrate that were interconnected to perform a logical function. Such logical function implementing simple logic operations provided the building blocks for the realization of switching networks. Further advances in technology enabled fabrication of many transistors on one semiconductor substr