Digital design width CPLD Application and VHDL - Chapter 11

Logic Gate Circuitry Nghiên cứu của chúng tôi các cổng logic và flip-flops trong các chương trước đã tập trung vào kỹ thuật số logic và phần lớn đã bỏ qua các thiết bị điện tử kỹ thuật số. Kỹ thuật số thiết bị logic là điện tử mạch với điện áp đặc trưng và dòng họ. Không có nghiên cứu nghiêm trọng của kỹ thuật số mạch là hoàn toàn không có một số kiểm tra của chủ đề này. Nó đặc biệt quan trọng để hiểu các yếu tố đầu vào và đầu ra của các thiết bị logic điện tử mạch. Biết. | CHAPTER iliil ll ll ll ll ll ll l ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll ll lll Logic Gate Circuitry OUTLINE Electrical Characteristics of Logic Gates Propagation Delay Fanout Power Dissipation Noise Margin Interfacing TTL and CMOS Gates Internal Circuitry of TTL Gates Internal Circuitry of CMOS Gates TTL and CMOS Variations CHAPTER OBJECTIVES Upon successful completion of this chapter you will be able to Name the various logic families most commonly in use today and state several advantages and disadvantages of each. Define propagation delay. Calculate propagation delay of simple circuits using data sheets. Define fanout and calculate its value using data sheets. Calculate power dissipation of TTL and CMOS circuits. Calculate noise margin of a logic gate from data sheets. Draw circuits that will interface various CMOS and TTL gates. Explain how a bipolar junction transistor can be used as a logic inverter. Describe the function of a TTL input transistor in all possible input states HIGH LOW and open-circuit. Explain the operation of a totem pole output. Illustrate how a totem pole output generates power line noise and describe how to remedy this problem. Illustrate why totem pole outputs cannot be tied together. Explain the difference between open-collector and totem pole outputs of a TTL gate. Illustrate the operation of TTL open-collector inverter NAND and NOR gates. Write the Boolean expression of a wired-AND circuit. Design a circuit that uses an open-collector gate to drive a high-current load. Calculate the value of a pull-up resistor at the output of an open-collector gate. Explain the operation of a tristate gate and name several of its advantages. Design a circuit using a tristate bus driver to direct the flow of data from one device to another. Describe the basic .