1. Microelectronics

2. Signals and Amplifiers

3. Introduction Microelectronics: IC electronics Basic Concepts Signals
12/5/2018
Introduction
Microelectronics: IC electronics
Basic Concepts
Signals
Amplification

4. Signals

5. Signals
Signal → {Transducer} → Electrical Signal → {Processing (Electronic)} → Information.
Thevenin
Norton

6. Example 1.1

7. Signals
Time Varying Signal

8. Frequency Spectrum of Signals

9. Periodic Signals
f = 1/T Hz
ω = 2πf rad/s

10. Frequency Spectrum of Signals
Linear System:
f(αx)= αf(x)
f(x+y)=f(x)+f(y)
sin(ωt) → { Linear System } → α sin(ωt+θ)
Fourier series or Fourier transform.
𝑓= 1 𝑇
𝜔=2𝜋𝑓= 2𝜋 𝑇

11. Frequency Spectrum of Signals
A symmetrical square-wave signal of amplitude V

12. Frequency Spectrum of Signals
Frequency Spectrum of the Periodic Square Wave

13. Frequency Spectrum of Signals
The Frequency Spectrum of a Non-Periodic Waveform

14. Analog and Digital Signals

15. Analog and Digital Signals
Analog Signal →{Sampling}→ Discrete Time Signal.

16. Analog and Digital Signals
Discrete Time Signal →{Quantization}→Digital Signal.
Digital Signal →{Electronics}→ Binary (e.g. 0 V & + 5V)

17. A/D (ADC) & D/A (DAC)
Many processing systems contain both analog and digital circuits

18. Amplifiers

19. The Simplest Processor Linearity: vo(t) = A vi(t)
Amplifiers
The Simplest Processor
Signal Amplification
Linearity: vo(t) = A vi(t)
A: Const
Preamplifier (V) & Power amplifier (I)

20. Amplifier Circuit Symbols

21. The Gain

22. The Gain Amplifier Gain Gain in Decibels Voltage Gain (Av)
20 log | Av |
Current Gain (Ai)
20 log |Ai|
Power Gain(Ap)
Av Ai
10 log |Ap|

23. Pdc + PI = PL + Pdissipated
The Amplifier Power Supplies
→ (PO - PI)
Pdc = V1 I1 + V2 I2
Pdc + PI = PL + Pdissipated ή

24. Example 1.2
𝑉 𝑆 =±10𝑉
𝑅 𝐿 =1𝑘Ω
𝑣 𝑖 =1sin 𝜔𝑡 𝑉
𝑣 𝑜 =9sin 𝜔𝑡 𝑉
𝐼 𝑆+ = 𝐼 𝑆− =9.5 𝑚𝐴
𝑖 𝑖 =0.1sin 𝜔𝑡 𝑚𝐴
𝐴 𝑣 = 9
=20𝑙𝑜𝑔9
𝐼 𝑜 =
9 𝑚𝐴
𝐴 𝑖 = 90
=20𝑙𝑜𝑔90
=39.1 dB
𝑃 𝐿 =
=40.5 mW
𝑃 𝐼 =
=0.05 mW
𝐴 𝑃 =
=810 mW
=29.1 dB
𝑃 𝑑𝑐 =
10×9.5+10×9.5=190𝑚𝑊
𝑃 𝐷𝑖𝑠𝑠𝑖𝑝 =
−40.5=149.6𝑚𝑊
𝜂=21.3%

25. Saturation
| L– | = | L+ |
= | VSS | - (1 V or 2 V)

26. Nonlinear Transfer Characteristics and Biasing
Non-Linearity
Q = Quiescent Point
= DC Biasing Point
= Operating Point

27. Symbol convention

28. Circuit Models for Amplifiers

29. Voltage Amplifiers

30. Cascaded Amplifiers
Example 1.3
Compute: AV, AI, & AP.

31. Other Amplifier Types

32. Voltage Amplifier

33. Current Amplifier

34. Transconductance Amplifier

35. Transresistance Amplifier

36. Other Amplifier Types

37. Relationships between the Four Amplifier Models

38. Determining Ri and Ro

39. Other Amplifier Types

40. Other Amplifier Types

41. Other Amplifier Types

42. Other Amplifier Types

43. Other Amplifier Types

44. Signal flows form the input to the output, with no feedback
Unilateral Models
Signal flows form the input to the output, with no feedback

45. Example 1.4

46. Example 1.4

47. Example 1.4

48. Example 1.4
Figure (a) Small-signal circuit model for a bipolar junction transistor (BJT). (b) The BJT connected as an amplifier with the emitter as a common terminal between input and output (called a common-emitter amplifier). (c) An alternative small-signal circuit model for the BJT.

50. Frequency Response of Amplifiers

51. Measuring The Amplifier Frequency Response
T(ω) ≡ Amplifier Transfer Function

52. Amplifier Bandwidth

53. Evaluating the Frequency Response of Amplifiers
S = ( σ + j ω ) ≡ Laplace Operator
= ( j ω ) at Steady State

54. Single Time Constant Networks

55. Single Time Constant Networks?
LP:

56. Single Time Constant Networks?
HP:

58. Bode Plot
Magnitude Response
Phase
Response

59. Bode Plot: Magnitude Response
Corner Frequency

60. Bode Plot: Phase Response

61. Magnitude Response Plot for STC LPF

62. Magnitude Response Plot for STC LPF

63. Magnitude Response Plot for STC LPF

64. Magnitude Response Plot for STC LPF

65. Magnitude Response Plot for STC LPF

66. 3 dB, Cut off , Critical, Corner Frequency
Magnitude Response Plot for STC LPF
3 dB, Cut off , Critical, Corner Frequency

67. 3 dB, Cut off , Critical, Corner Frequency
Magnitude Response Plot for STC LPF
3 dB, Cut off , Critical, Corner Frequency

68. Phase Response Plot for STC LPF

69. Phase Response Plot for STC LPF
12/5/2018
Phase Response Plot for STC LPF ∞

70. Bode Plot for STC HPF

71. Bode Plot for STC HPF

72. Example 1.5
Calculate AV(ω=0), ω0(3-dB), & ω(AV = 0-dB)

73. Example 1.5

74. Example 1.5

75. Example 1.5

76. Example 1.5

77. Example 1.5

78. Classification of Amplifiers Based on Frequency Response

79. Capacitive Coupling vs. Direct Coupling (dc) Amplifiers