数字逻辑3_1.pptVIP

2311321 555 3.1 Logic functions and logic gates 3.2 CMOS Logic Switch models CMOS Inverter Circuit (3.3.3 P88) Switch model CMOS NAND Gate Switch model Three-input NAND CMOS AND Gate (3.3.6 P94) CMOS NOR Gate 3.2.3. CMOS Static Electrical Behavior (3.5 P101) 3.2.4. CMOS Dynamic Electrical Behavior 3.6 P114 Exercise PRINCIPLES AND PRACTICES Chapter 3 Digital Circuits 1. AND （与门） function：produces a 1 output if and only if all of its inputs are 1 (输入有0，输出为0) expression：Z=A AND B；Z=A·B；Z=AB 0 0 0 0 1 0 1 0 0 1 1 1 Truth table symbol A B Z A B Z A B Z Truth table：a table lists all combinations of input values and the output values produced by each one. (P82) Distinctive shape Rectangular outline 2. OR（或门） function：produces a 1 if and only if one or more of its inputs are 1 (输入有1，输出为1) expression：Z=A OR B；Z=A+B A B Z truth table ≥1 A B Z A B Z symbol 0 0 0 0 1 1 1 0 1 1 1 1 the difference with binary addition？ 3. NOT（非门, 反相器） function：produces an output value that is the oppsite of its input value (输出对输入取反) expression：Z=NOT A; Z=X’; Z= A Z 0 1 1 0 truth table 1 Z A A Z symbol 4. Others NAND (与非) :(XY)’ , XY NOR (或非):(X+Y)’, X+Y XOR (异或):X⊕Y XNOR (同或): (X⊕Y)’, X⊙Y Buffer (缓冲) =1 ≥1 =1 = Positive logic (正逻辑) and Negative logic(负逻辑) Positive logic：assigning 0 to low and 1 to high Negative logic：assigning 1 to low and 0 to high Logic family： Bipolar junction transistor circuits：TTL，ECL MOS transistor circuits：NMOS, PMOS, CMOS CMOS is the most commonly used logic family CMOS Logic Categories 4000-series CMOS Part number– mmFAMnn: mm: 74/54，commercial/military FAM：alphabetic family mnemonic HC/HCT: High Speed CMOS(TTL compatible) AHC/AHCT:Advanced High-Speed CMOS FCT/FCT-T:Fast CMOS,TTL compatible(TTL compatible with TTL VOH) LV:Low voltage nn：numeric function designator 3.2.1.MOS Transistors （3.3.2 P87） MOSFET: metal-oxide semiconductor field-effect transistor P