Test Bank For Digital Electronics Principles And Applications 8Th Edition By Roger Tokheim

Chapter 003-Logic Gates True / False Questions 1. The basic building block of any digital circuit is a flip-flop. True False 2. Positive logic is most often used in digital electronics. True False 3. The Boolean expression is a universal language used by engineers and technicians in analog electronics. True False 4. The unique output of the AND function is a high output only when all inputs are high. True False 5. The AND gate is sometimes called the "any or all" gate. True False 6. The NOT circuit has one input and one output. True False 7. The terms negated, complemented, and inverted mean the same thing. True False 8. The unique output of the NAND function is a low output only when all inputs are low. True False 3-1 Chapter 003-Logic Gates 9. The NOR gate is not the same as the OR gate in operation. True False 10. The exclusive NOR gate is sometimes referred to as the "odd but not even gate." True False 11. Floating inputs on CMOS ICs can harm the IC. True False 12. Manufacturers' data manuals include traditional logic symbols and are recently including the newer IEEE functional logic symbols. True False 13. The bubble at the input of an inverter indicates that the active state is high. True False 14. A pull-down resistor is often attached to the input of a gate in order to pull the input to the gate low when input switch is open. True False 15. It is uncommon for logic functions to be programmed using software. True False 16. When using PBASIC, remark statements are used to clarify the program and are not executed by the microcontroller. True False 3-2 Chapter 003-Logic Gates 17. The unique characteristic of the XOR gate is that it produces a high output only when an odd number of high inputs are present. True False 18. NAND gates are not as widely used as are other logic gates. True False 19. Invert bubbles at the input of the AND gate convert it into a NOR function. True False 20. The CMOS family is a very low power and widely used family of digital ICs. True False Multiple Choice Questions 21. Which logic gate provides a low output only when an odd number of inputs are high? A. and B. or C. exclusive OR D. exclusive NOR 22. Which type gate is generally more widely available than any other gate? A. and B. or C. nor D. nand 3-3 Chapter 003-Logic Gates 23. How many two-input NAND gates are required to produce a two-input exclusive OR gate? A. 1 B. 2 C. 3 D. 4 24. Which of the following could be a Boolean expression for a three-input or gate? A. A + B = Y B. A + B + C = Y C. A ∙ B ∙ C = Y D. A = Y 25. Which family of digital ICs uses parts comparable to IGFETs? A. bipolar B. CMOS C. DIP D. SMT 26. The letters LS in the core part number of a 7400 series IC stand for A. CMOS B. Fast Fairchild C. low signal D. low-power Schottky 27. If caution is not exercised, CMOS ICs can be damaged by A. tying unused inputs to ground B. tying unused inputs to VDD C. static charges D. using them as NAND gates 3-4 Chapter 003-Logic Gates 28. On a logic probe, the ______ lead is connected to the positive (+) of the power supply. A. black B. white C. red D. green 29. In practical electronic equipment most digital ICs are mounted on A. a chassis B. a printed circuit board C. an analog IC D. a ribbon cable 30. The first step in troubleshooting should be to A. use your senses B. replace the ICs C. replace the power supply D. measure all resistors 31. Which of the following is sometimes referred to as the "all or nothing" gate? A. OR B. NAND C. NOR D. AND 32. A logic _______________ is a circuit that can decide to say yes or no at the output based upon inputs. A. function B. probe C. gate D. switch 3-5 Chapter 003-Logic Gates 33. In Boolean algebra is the algebra of _______________. A. logic B. digital circuitry C. engineers D. binary 34. The _________ for a gate gives all the possible input combinations and the resulting outputs. A. logic function B. truth table C. logic symbol D. invert function 35. The NOT circuit is another name for a(n) _______________. A. encoder B. decoder C. inverter D. all or nothing gate 36. The noninverting _______________ serves no logical purpose, but is used to supply greater drive current at its output. A. drive current B. invert bubble C. switch D. buffer 37. The little invert bubble on the right end of a logic symbol means to invert the _______________. A. output B. input C. logic gate D. logic function 3-6 Chapter 003-Logic Gates 38. The unique output from the NOR gate is _______________ only when all inputs are ____________. A. low, low B. high, high C. low, high D. high, low 39. ICs that are much smaller and have shorter pins bent to be soldered to the traces on the top of a PC board are commonly called _______________ packages. A. NAND B. AND C. LED D. SMT 40. This is the logic symbol for a(n) A. AND gate B. NOT gate (inverter) C. OR gate D. ANAND gate 41. If a National Semiconductor digital DIP IC had the number 74HC08N printed on the top, what type of component would it be? A. PPI B. XS3 C. TTL D. CMOS 3-7 Chapter 003-Logic Gates 42. When using 4000 series CMOS, what is the pin labeled that is connected to the positive of the power supply? A. VPP B. VSS C. VDD D. GND 43. This is the logic symbol for what type of gate? A. XOR B. OR C. NOR D. AND 44. This is an alternative logic symbol for what type gate? A. xor B. or C. nor D. and 3-8 Chapter 003-Logic Gates Key True / False Questions 1. (p. 43) The basic building block of any digital circuit is a flip-flop. FALSE The logic gate is the basic building block of any digital circuit. Difficulty: 1 Easy 2. (p. 44) Positive logic is most often used in digital electronics. TRUE Difficulty: 2 Medium 3. (p. 45) The Boolean expression is a universal language used by engineers and technicians in analog electronics. FALSE The Boolean expression is used by engineers and technicians in digital electronics. Difficulty: 2 Medium 4. (p. 45) The unique output of the AND function is a high output only when all inputs are high. TRUE Difficulty: 2 Medium 3-9 Chapter 003-Logic Gates Key 5. (p. 46) The AND gate is sometimes called the "any or all" gate. FALSE The OR gate is sometimes called the "any or all" gate. Difficulty: 1 Easy 6. (p. 45) The NOT circuit has one input and one output. TRUE Difficulty: 1 Easy 7. (p. 48) The terms negated, complemented, and inverted mean the same thing. TRUE Difficulty: 2 Medium 8. (p. 46) The unique output of the NAND function is a low output only when all inputs are low. FALSE The unique output from the NAND gate is a LOW only when all inputs are HIGH. Difficulty: 2 Medium 9. (p. 51) The NOR gate is not the same as the OR gate in operation. TRUE Difficulty: 2 Medium 3-10 Chapter 003-Logic Gates Key 10. (p. 49) The exclusive NOR gate is sometimes referred to as the "odd but not even gate." FALSE The exclusive OR gate is sometimes referred to as the "odd but not even gate." Difficulty: 3 Hard 11. (p. 71) Floating inputs on CMOS ICs can harm the IC. TRUE Difficulty: 2 Medium 12. (p. 72) Manufacturers' data manuals include traditional logic symbols and are recently including the newer IEEE functional logic symbols. TRUE Difficulty: 3 Hard 13. (p. 73) The bubble at the input of an inverter indicates that the active state is high. FALSE The bubble at the input of an inverter indicates that the active state is low. Difficulty: 3 Hard 14. (p. 75) A pull-down resistor is often attached to the input of a gate in order to pull the input to the gate low when input switch is open. TRUE Difficulty: 2 Medium 3-11 Chapter 003-Logic Gates Key 15. (p. 77) It is uncommon for logic functions to be programmed using software. FALSE Logic functions are commonly programmed using software. Difficulty: 2 Medium 16. (p. 79) When using PBASIC, remark statements are used to clarify the program and are not executed by the microcontroller. TRUE Difficulty: 3 Hard 17. (p. 53) The unique characteristic of the XOR gate is that it produces a high output only when an odd number of high inputs are present. TRUE Difficulty: 2 Medium 18. (p. 56) NAND gates are not as widely used as are other logic gates. FALSE NAND gates are more widely available than most other kinds of gates. Difficulty: 2 Medium 19. (p. 61) Invert bubbles at the input of the AND gate convert it into a NOR function. TRUE Difficulty: 3 Hard 3-12 Chapter 003-Logic Gates Key 20. (p. 62) The CMOS family is a very low power and widely used family of digital ICs. TRUE Difficulty: 1 Easy Multiple Choice Questions 21. (p. 54) Which logic gate provides a low output only when an odd number of inputs are high? A. and B. or C. exclusive OR D. exclusive NOR Difficulty: 3 Hard 22. (p. 56) Which type gate is generally more widely available than any other gate? A. and B. or C. nor D. nand Difficulty: 2 Medium 23. (p. 56) How many two-input NAND gates are required to produce a two-input exclusive OR gate? A. 1 B. 2 C. 3 D. 4 Difficulty: 3 Hard 3-13 Chapter 003-Logic Gates Key 24. (p. 57) Which of the following could be a Boolean expression for a three-input or gate? A. A + B = Y B. A + B + C = Y C. A ∙ B ∙ C = Y D. A = Y Difficulty: 1 Easy 25. (p. 62) Which family of digital ICs uses parts comparable to IGFETs? A. bipolar B. CMOS C. DIP D. SMT Difficulty: 2 Medium 26. (p. 63) The letters LS in the core part number of a 7400 series IC stand for A. CMOS B. Fast Fairchild C. low signal D. low-power Schottky The letters "LS" in the center of the core number designate the type of TTL circuitry used in the IC. Difficulty: 3 Hard 3-14 Chapter 003-Logic Gates Key 27. (p. 62) If caution is not exercised, CMOS ICs can be damaged by A. tying unused inputs to ground B. tying unused inputs to VDD C. static charges D. using them as NAND gates Care must be taken when removing the 4081 from its conductive foam storage because CMOS ICs can be damaged by static charges. Difficulty: 1 Easy 28. (p. 69) On a logic probe, the ______ lead is connected to the positive (+) of the power supply. A. black B. white C. red D. green The red lead is connected to the positive (1) of the power supply while the black lead of the logic probe is connected to the negative (2) or GND of the power supply. Difficulty: 1 Easy 29. (p. 68) In practical electronic equipment most digital ICs are mounted on A. a chassis B. a printed circuit board C. an analog IC D. a ribbon cable Difficulty: 1 Easy 3-15 Chapter 003-Logic Gates Key 30. (p. 64) The first step in troubleshooting should be to A. use your senses B. replace the ICs C. replace the power supply D. measure all resistors Feel the flat top of the ICs to determine if they are hot. Some ICs operate cool; others run slightly warm. CMOS ICs should always be cool. Look for broken connections, solder bridges, broken PC board traces, and bent IC pins. Smell for possible overheating. Look for signs of excessive heat, such as discoloration or charring. Difficulty: 1 Easy 31. (p. 43) Which of the following is sometimes referred to as the "all or nothing" gate? A. OR B. NAND C. NOR D. AND Difficulty: 1 Easy 32. (p. 44) A logic _______________ is a circuit that can decide to say yes or no at the output based upon inputs. A. function B. probe C. gate D. switch Difficulty: 1 Easy 3-16 Chapter 003-Logic Gates Key 33. (p. 45) In Boolean algebra is the algebra of _______________. A. logic B. digital circuitry C. engineers D. binary Difficulty: 1 Easy 34. (p. 44) The _________ for a gate gives all the possible input combinations and the resulting outputs. A. logic function B. truth table C. logic symbol D. invert function Difficulty: 1 Easy 35. (p. 48) The NOT circuit is another name for a(n) _______________. A. encoder B. decoder C. inverter D. all or nothing gate Difficulty: 2 Medium 36. (p. 48) The noninverting _______________ serves no logical purpose, but is used to supply greater drive current at its output. A. drive current B. invert bubble C. switch D. buffer Difficulty: 2 Medium 3-17 Chapter 003-Logic Gates Key 37. (p. 50) The little invert bubble on the right end of a logic symbol means to invert the _______________. A. output B. input C. logic gate D. logic function Difficulty: 2 Medium 38. (p. 52) The unique output from the NOR gate is _______________ only when all inputs are ____________. A. low, low B. high, high C. low, high D. high, low Difficulty: 2 Medium 39. (p. 63) ICs that are much smaller and have shorter pins bent to be soldered to the traces on the top of a PC board are commonly called _______________ packages. A. NAND B. AND C. LED D. SMT Difficulty: 2 Medium 3-18 Chapter 003-Logic Gates Key 40. (p. 48) This is the logic symbol for a(n) A. AND gate B. NOT gate (inverter) C. OR gate D. ANAND gate Difficulty: 1 Easy 41. (p. 63) If a National Semiconductor digital DIP IC had the number 74HC08N printed on the top, what type of component would it be? A. PPI B. XS3 C. TTL D. CMOS Difficulty: 3 Hard 3-19 Chapter 003-Logic Gates Key 42. (p. 66) When using 4000 series CMOS, what is the pin labeled that is connected to the positive of the power supply? A. VPP B. VSS C. VDD D. GND Difficulty: 2 Medium 43. (p. 53) This is the logic symbol for what type of gate? A. XOR B. OR C. NOR D. AND Difficulty: 1 Easy 44. (p. 61) This is an alternative logic symbol for what type gate? A. xor B. or C. nor D. and Difficulty: 3 Hard 3-20