1. CHAPTER 1 Digital Concepts
Digital Fundamentals
CHAPTER 1 Digital Concepts

2. Digital and Analog Quantities
Digital quantities have discrete sets of values
Analog quantities have continuous values

3. Binary Digits, Logic Levels, and Digital Waveforms
The two binary digits are designated 0 and 1
They can also be called LOW and HIGH, where LOW = 0 and HIGH = 1

4. Figure 1–3 A basic audio public address system.
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5. Figure 1–5 Logic level ranges of voltage for a digital circuit.
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6. Binary values are also represented by voltage levels.
Figure 1– Ideal pulses.
Binary values are also represented by voltage levels.
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7. Figure 1–7 Nonideal pulse characteristics.
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8. Binary Digits, Logic Levels, and Digital Waveforms
tw = pulse width
T = period of the waveform
f = frequency of the waveform

9. Binary Digits, Logic Levels, and Digital Waveforms
The duty cycle of a binary waveform is defined as:

10. Figure 1–9
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11. Figure 1– Example of a clock waveform synchronized with a waveform representation of a sequence of bits.
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12. Figure 1–11 Example of a timing diagram.
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13. Figure 1– Illustration of serial and parallel transfer of binary data. Only the data lines are shown.
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14. Figure 1–13
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15. Figure 1–14
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16. Basic Logic Operations
There are only three basic logic operations:

17. Basic Logic Operations
The NOT operation
When the input is LOW, the output is HIGH
When the input is HIGH, the output is LOW
The output logic level is always opposite the input logic level.

18. Basic Logic Operations
The AND operation
When any input is LOW, the output is LOW
When both inputs are HIGH, the output is HIGH

19. Basic Logic Operations
The OR operation
When any input is HIGH, the output is HIGH
When both inputs are LOW, the output is LOW

20. Overview of Basic Logic Functions
Comparison function
Arithmetic functions
Code conversion function
Encoding function
Decoding function
Data selection function
Data storage function
Counting function

21. Figure 1–19 The comparison function.
Compares two binary values and determines whether or not they are equal
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22. Overview of Basic Logic Functions
Arithmetic functions
Perform the basic arithmetic operations on two binary values:
Addition
Subtraction of two values
Multiplication
Division

23. Figure 1–20 The addition function.
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24. Code conversion function
Converts, or translates, information from one code format to another
Encoding function
Converts non-binary information into a binary code
Decoding function
Converts binary-coded information into a non-binary form

25. Figure 1– An encoder used to encode a calculator keystroke into a binary code for storage or for calculation.

26. Figure 1–22 A decoder used to convert a special binary code into a 7-segment decimal readout.
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27. Overview of Basic Logic Functions
Data selection function
Multiplexer (mux)
Switches digital data from any number of input sources to a single output line
Demultiplexer (demux)
switches digital data from a single input to any number of output lines

28. Figure 1–23 Illustration of a basic multiplexing/demultiplexing application.
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29. Overview of Basic Logic Functions
Data storage function
Retains binary data for a period of time
Flip-flops (bistable multvibrators)
Registers
Semiconductor memories
Magnetic-media memories
Optical-media memories

30. Figure 1–24 Example of the operation of a 4-bit serial shift register
Figure 1– Example of the operation of a 4-bit serial shift register. Each block represents one storage “cell” or flip-flop.
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31. Figure 1–25 Example of the operation of a 4-bit parallel shift register.
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32. Figure 1–26 Illustration of basic counter operation.
Counting function
Generates sequences of digital pulse that represent numbers
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33. Fixed-Function Integrated Circuits
IC package styles
Dual in-line package (DIP)
Small-outline IC (SOIC)
Flat pack (FP)
Plastic-leaded chip carrier (PLCC)
Leadless-ceramic chip carrier (LCCC)

34. Figure 1– Cutaway view of one type of fixed-function IC package showing the chip mounted inside, with connections to input and output pins.
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35. Fixed-Function Integrated Circuits
Dual in-line package (DIP)

36. Fixed-Function Integrated Circuits
Small-outline IC (SOIC)

37. Figure 1–29 Examples of SMT package configurations.
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38. Figure 1–30 Pin numbering for two standard types of IC packages
Figure 1– Pin numbering for two standard types of IC packages. Top views are shown.
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39. Introduction to Programmable Logic
SPLD—Simple programmable logic devices
CPLD—Complex programmable logic devices
FPGA—Field-programmable gate arrays

40. Figure 1–31 Programmable logic.
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41. Introduction to Programmable Logic
SPLD
PAL (programmable array logic)
GAL (generic array logic)
PLA (programmable logic array)
PROM (programmable read-only memory)

42. Figure 1–32 Block diagrams of simple programmable logic devices (SPLDs).
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43. Figure 1–34 General block diagram of a CPLD.
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44. Figure 1–36 Basic structure of an FPGA.
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45. Figure 1–38 Basic configuration for programming a PLD or FPGA.
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46. Test and Measurement Instruments
Analog Oscilloscope
Digital Oscilloscope
Logic Analyzer
Logic Probe, Pulser, and Current Probe
DC Power Supply
Function Generator
Digital Multimeter

47. Figure 1–40 A typical dual-channel oscilloscope
Figure 1– A typical dual-channel oscilloscope. Used with permission from Tektronix, Inc.
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48. Figure 1–41 Comparison of analog and digital oscilloscopes.
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49. Figure 1–42 Block diagram of an analog oscilloscope.
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50. Figure 1–43 Block diagram of a digital oscilloscope.
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51. Figure 1–44 A typical dual-channel oscilloscope
Figure 1– A typical dual-channel oscilloscope. Numbers below screen indicate the values for each division on the vertical (voltage) and horizontal (time) scales and can be varied using the vertical and horizontal controls on the scope.
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52. Figure 1–45 Comparison of an untriggered and a triggered waveform on an oscilloscope.
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53. Figure 1–46 Displays of the same waveform having a dc component.
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54. Figure 1–47 An oscilloscope voltage probe
Figure 1– An oscilloscope voltage probe. Used with permission from Tektronix, Inc.
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55. Figure 1–48 Probe compensation conditions.
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56. Figure 1–49
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57. Figure 1–50 Typical logic analyzer
Figure 1– Typical logic analyzer. Used with permission from Tektronix, Inc.
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58. Figure 1–51 Simplified block diagram of a logic analyzer.
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59. Figure 1–52 Two logic analyzer display modes.
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60. Figure 1–53 A typical multichannel logic analyzer probe
Figure 1– A typical multichannel logic analyzer probe. Used with permission from Tektronix, Inc.
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61. Figure 1–54 Typical signal generators
Figure 1– Typical signal generators. Used with permission from Tektronix, Inc.
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62. Figure 1– Illustration of how a logic pulser and a logic probe can be used to apply a pulse to a given point and check for resulting pulse activity at another part of the circuit.
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63. Figure 1–56 Typical dc power supplies. Courtesy of B+K Precision.®
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64. Figure 1–57 Typical DMMs. Courtesy of B+K Precision.®
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65. Figure 1–60
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66. Figure 1–61
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67. Figure 1–62
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68. Figure 1–63

69. Figure 1–64