电子信息与通信工程专业英语lesson2-2(太原理工大学版).

1、2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语1 Chapter 2 Circuit System and Design Outlinel2.1 Circuit and Systeml2.2 Analog and Digital Circuits Designl2.3 Radio Receiver Circuit 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语22.2 Analog and Digital Circuits Design OutlinelAnalog circuits lDigit Circuits2022-1-25通信与信息工程

2、专业英语教程电子信息与通信工程专业英语3Terminologylbipolar adj.双极型lCMOS abbr. Complementary Metal Oxide Semiconductor 互补型金属氧化物半导体lsemiconducting material 半导体材料lIntegrated circuits 集成电路ltransistor n.晶体管lDC abbr. Direct Current 直流lAC abbr. Alternate Current 交流ldigital adj.数字的, 计数的lbinary adj. 具有两个的;二进制的; 二变量的lBoolean al

3、gebra 布尔代数lpositive adj. 确实的;积极的; 肯定的;现实的;正的;阳性的2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语4lnegative adj. 否定的, 否认的;反面的, 消极的反对的;负的;阴极的lhexadecimal adj. 十六进制的lnumber system 计数制lCommutative Law 交换律lAssociative Law 结合律lDistributive Law 分配率linverter n. 变换器; 倒相器, 倒换器; 反演器; 逆变器; “非”门ltruth table n.真值表lcombination

4、al adj. 组合的lsequential adj. 时序的lFlip-flop n.触发器2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语5lAnalog circuits are circuits dealing with signals free to vary from zero to full power supply voltage. lAnalog circuits are often referred to as linear circuits to emphasize the valid continuity of signal range forbi

5、dden in digital circuits, but this label is unfortunately misleading. IntroductionText tour1.Analog circuitslModern circuit design is a mixed signal endeavor thanks to the availability of sophisticated process technologies that make available bipolar and CMOS, power and signal, passive and active co

6、mponents on the same circuit. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语6lJust because a voltage or current signal is allowed to vary smoothly between the extremes of zero and full power supply limits does not necessarily mean that all mathematical relationships between these signals are linear in the stra

7、ight-line or proportional sense of the word. Many so-called linear circuits are quite nonlinear in their behavior, either by necessity of physics or by design. lThis relative mobility of electrons within a material is known as electric conductivity. Conductivity is determined by the types of atoms i

8、n a material (the number of protons in each atoms nucleus, determining its chemical identity) and how the atoms are linked together with one another. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语7 NPN transistorslIn fact, in the most basic and most cost effective analog IC processes, the chip designer has at

9、its disposal just that a good NPN transistor. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语8lIn this component the current flow enters the collector and base and exits the emitter. Simply stated, the transistor conducts a collector current which is a copy of the base current amplified by a factor of beta . It

10、 follows that the emitter current is one plus beta times the base current. A typical value for the amplification factor is 100. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语9lThe PNP transistor is complementary to the NPN, with the current flow entering the emitter and exiting the collector and base, the oppo

11、site of what happens in the NPN. lSimplicity dictates that PNPs are a by-product of the NPN construction, hence they often have less beta current gain and are slower than NPNs. PNP transistors2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语10MOS transistorslThe dual of Bipolar NPN and PNP transistors in CMOS tec

12、hnology are the P-Channel and N-Channel MOS transistors . The general function of the transistors is the same independently as their implementation but there are pros and cons to using both technologies. Generally speaking, the base, the emitter, and the collector of the bipolar transistor are analo

13、gous to the gate, source and drain of the MOS transistor, respectively. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语11l The bipolar transistors main problem, which is not present in CMOS, is their need for a base current in order to function. Such current is a net transfer loss from emitter to collector. Whi

14、le the base current is small in small signal operation, in power applications, where the transistor is used as a switch, the base current necessary to keep the transistor on can be very high.2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语12lThis high base current can lead to implementations with very poor effic

15、iency. With the popularity of portable electronics and the need to extend battery life, it is no wonder that CMOS often tends to have the upper hand over bipolar technologies. The advantage of bipolar over CMOS that it has better trans-conductance gain and better matching, leading to better differen

16、tial input gain stages and better voltage references. The best performance processes are mixed-mode BiCMOS (Bipolar and CMOS) or BCD (Bipolar CMOS and DMOS) processes in which the designer can use the best component for the task at hand.2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语132. Digit Circuits lBoolean

17、 algebra fundamentalslThe phrase “Digital electronics” is used to describe those circuit systems which primarily operate with the use of only two different voltage levels or two other binary states. Analog devices and systems process time-varying signals that can take on any value across a continuou

18、s range of voltage, current or other metric. The difference is that we can pretend that they dont.2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语14lThe NOT operation changes the value to the complement of the value. This is also referred to as inversion or negation. lThe AND operation is a Boolean multiply and

19、is 1 only when all values are 1. The AND is like the old string of Christmas lights. All the lights have to work to have the stringy light. l The OR operation results in a 1 if any of the values are 1. In Boolean algebra, 1+1=1 is valid. Logically the statement means if there are one or more true va

20、lues, the result is true.2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语15lCommutative Law: A + B = B + AlAssociative Law of Addition: A+B + C=A+(B+C)lAssociative Law of multiplication: A(BC) = (AB)ClDistributive Law: A(B+C) = AB + AClIdentity: 1A=A, 0+A=AlComplement: A+A=1.AA=0lDe Morgans Theorem: BABA2022-1-2

21、5通信与信息工程专业英语教程电子信息与通信工程专业英语16lLogic gateslIn general, a gate has one or more inputs and produces an output that is a function of the current input value(s). With each logic element there is a “truth table” that explains how the unit works. And there is a symbol to represent every gate.lThe basic ele

22、ctronic digital operations are also NOT, AND, OR, but there are combinations of these that are also commonly used: the NAND, NOR, and EXCLUSIVE NOR. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语17lCombinational logic and sequential logic circuitlLogic circuits are classified into two types: combinational and

23、sequential. A combinational logic is one whose outputs depend only on its current input. A combinational logic circuit may contain an arbitrary number of logic gates and inverters but no feedback loops( a signal path of a circuit that allows the output of a gate to propagate back to the input of tha

24、t same gate). 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语18lWhen the input is combined with the previous state of the logic circuits, it is referred to as sequential logic. The use of the previous state is called feedback. The outputs of sequential logic circuit depend not only on the current inputs but als

25、o on the past sequence of inputs, possibly arbitrarily far back in time. A seal-in circuit is an example of a sequential logic circuit. 2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语19lIn the analysis, use logic diagram and proceed to a formal description of the function performed by that circuit, such as a tr

26、uth table or a logic expression. In the synthesis, from a formal description and proceeding to a logic diagram. We have learned that there are five possible representations for a combinational logic function:l1. truth tablel2. an algebraic sum of minterms, the canonical suml3. a minterm list using t

27、he notationl4. an algebraic product of maxterms, the canonical productl5 a maxterm list using the notation2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语20lKarnaugh map, like Boolean algebra, is a simplification tool applicable to digital logic. Boolean simplification is actually faster than the Karnaugh map fo

28、r a task involving two or fewer Boolean variables. It is still quite usable at three variables, but a bit slower. At four input variables, Boolean algebra becomes tedious. Karnaugh maps are both faster and easier. Karnaugh maps work well for up to six input variables, are usable for up to eight vari

29、ables. For more than six to eight variables, simplification should be by CAD (computer automated design). It simplifies a logic function by combining pairs of adjacent 1 cells into a Sum-Of-Products terms that covers all of the 1 cells. Form groups of 1s to cover all 0s. The Product-Of-Sums simplifi

30、ed result is built. By the definition of minimal cost solution, the SOP solution is simpler.2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语21lFlip-flop is the common name given to two-state devices which offer basic memory for sequential logic operations. Flip-flops are heavily used for digital data storage and

31、 transfer and are commonly used in banks called registers for the storage of binary numerical data. Flip-Flops2022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语222022-1-25通信与信息工程专业英语教程电子信息与通信工程专业英语23lIn an S-R latch, activation of the S input sets the circuit, while activation of the R input resets the circuit. If both S and R inputs are activated simultaneously, the circuit will be in an invalid condition.lThe J-K flip-flop is a modified version of an S-R flip-flop with no “invalid” or “illegal” output state. So a J-K flip-flop is