This document provides an overview of a course on RF integrated circuit design and testing for wireless communications. The course covers semiconductor technologies for RF circuits, basic RF device characteristics, RF front-end design including LNAs and mixers, frequency synthesizer design including PLLs and VCOs, concepts of RF testing including distortion and noise measurements, and RFIC system-on-chip testing. The schedule outlines lectures on introduction to RF components, power and gain, distortion, noise, RF design topics, analog and embedded test, and built-in self-test.

1. RFIC Design and Testing for Wireless
Communications
A PragaTI (TI India Technical University) Course
July 18, 21, 22, 2008
Lecture 1: Introduction
Vishwani D. Agrawal
Foster Dai
Auburn University, Dept. of ECE, Auburn, AL 36849, USA
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2. Abstract
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This course discusses design and testing of RF integrated circuits
(RFIC). It is suitable for engineers who plan work on RFIC but did not
have training in that area, those who work on IC design and wish to
sharpen their understanding of modern RFIC design and test methods,
and engineering managers. It is an abbreviated version of a one-
semester university course. Specific topics include semiconductor
technologies for RF circuits used in a wireless communications system;
basic characteristics of RF devices – linearity, noise figure, gain; RF
front-end design – LNA, mixer; frequency synthesizer design – phase
locked loop (PLL), voltage controlled oscillator (VCO); concepts of
analog, mixed signal and RF testing and built-in self-test; distortion –
theory, measurements, test; noise – theory, measurements, test; RFIC
SOCs and their testing.

3. Objectives
 To acquire introductory knowledge about integrated circuits
(IC) used in radio frequency (RF) communications systems.
 To learn basic concept of design of RFIC.
 To learn basic concepts of RFIC testing.
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4. Outline
 Introduction to VLSI devices used in RF communications
■ SOC and SIP
■ Functional components
■ Technologies
 Design concepts and selected case studies
 Test concepts
■ Basic RF measurements
■ Distortion characteristics
■ Noise
■ SOC testing and built-in self-test (BIST)
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5. References
1. M. L. Bushnell and V. D. Agrawal, Essentials of Electronic Testing for Digital,
Memory & Mixed-Signal VLSI Circuits, Boston: Springer, 2000.
2. J. Kelly and M. Engelhardt, Advanced Production Testing of RF, SoC, and
SiP Devices, Boston: Artech House, 2007.
3. B. Razavi, RF Microelectronics, Upper Saddle River, New Jersey: Prentice
Hall PTR, 1998.
4. J. Rogers, C. Plett and F. Dai, Integrated Circuit Design for High-Speed
Frequency Synthesis, Boston: Artech House, 2006.
5. K. B. Schaub and J. Kelly, Production Testing of RF and System-on-a-Chip
Devices for Wireless Communications, Boston: Artech House, 2004.
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6. Schedule, July 18, 2008
09:00AM – 10:30AM Lecture 1 Introduction Agrawal
10:30AM – 11:00AM Break
11:00AM – 12:30PM Lecture 2 Power & Gain Agrawal
12:30PM – 01:30PM Lunch
01:30PM – 03:00PM Lecture 3 Distortion Agrawal
03:00PM – 03:30PM Break
03:30PM – 05:00PM Lecture 4 Noise Agrawal
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7. Schedule, July 21, 2008
09:00AM – 10:30AM Lecture 5 RF Design I Dai
10:30AM – 11:00AM Break
11:00AM – 12:30PM Lecture 6 RF Design II Dai
12:30PM – 01:30PM Lunch
01:30PM – 03:00PM Lecture 7 RF Design III Dai
03:00PM – 03:30PM Break
03:30PM – 05:00PM Lecture 8 RF Design IV Dai
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8. Schedule, July 22, 2008
09:00AM – 10:30AM Lecture 9 RF Design V Dai
10:30AM – 11:00AM Break
11:00AM – 12:30PM Lecture 10 RF Design VI Dai
12:30PM – 01:30PM Lunch
01:30PM – 03:00PM Lecture 11 ATE & SOC Test Agrawal
03:00PM – 03:30PM Break
03:30PM – 05:00PM Lecture 12 BIST Dai
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9. An RF Communications System
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Duplexer
LNA
PA
LO
LO
LO
VGA
VGA
Phase
Splitter
Phase
Splitter
Digital
Signal
Processor
(DSP)
ADC
ADC
DAC
DAC
90°
90°
0°
0°
RF IF BASEBAND
Superheterodyne Transceiver

10. An Alternative RF Communications System
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Duplexer LNA
PA
LO
LO
Phase
Splitter
Phase
Splitter
Digital
Signal
Processor
(DSP)
ADC
ADC
DAC
DAC
90°
90°
0°
0°
RF BASEBAND
Zero-IF (ZIF) Transceiver

11. Components of an RF System
Radio frequency
● Duplexer
● LNA: Low noise amplifier
● PA: Power amplifier
● RF mixer
● Local oscillator
● Filter
Intermediate frequency
● VGA: Variable gain amplifier
● Modulator
● Demodulator
● Filter
Mixed-signal
● ADC: Analog to digital
converter
● DAC: Digital to analog
converter
Digital
● Digital signal processor
(DSP)
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12. Duplexer
TDD: Time-Division
Duplexing
● Same Tx and Rx frequency
● RF switch (PIN or GaAs FET)
● Less than 1dB loss
FDD: Frequency-
Division Duplexing
● Tx to Rx coupling (-50dB)
● More loss (3dB) than TDD
● Adjacent channel leakage
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Rx
Tx
TDD command
Rx
Tx
fr
fr
ft
ft

13. LNA: Low Noise Amplifier
 Amplifies received RF signal
 Typical characteristics:
● Noise figure 2dB
● IP3 – 10dBm
● Gain 15dB
● Input and output impedance 50Ω
● Reverse isolation 20dB
● Stability factor > 1
 Technologies:
● Bipolar
● CMOS
 Reference: Razavi, Chapter 6.
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14. PA: Power Amplifier
 Feeds RF signal to antenna for transmission
 Typical characteristics:
● Output power +20 to +30 dBm
● Efficiency 30% to 60%
● IMD – 30dBc
● Supply voltage 3.8 to 5.8 V
● Gain 20 to 30 dB
● Output harmonics – 50 to – 70 dBc
● Power control On-off or 1-dB steps
● Stability factor > 1
 Technologies:
● GaAs
● SiGe
 Reference: Razavi, Chapter 9. 14

15. Mixer or Frequency (Up/Down) Converter
 Translates frequency by subtracting local oscillator (LO)
frequency
 Typical characteristics:
● Noise figure 12dB
● IP3 +5dBm
● Gain 10dB
● Input impedance 50Ω
● Port to port isolation 10-20dB
 Tecnologies:
● Bipolar
● MOS
 Reference: Razavi, Chapter 6.
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16. Passive Mixer
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V(IF)
RL
nFET
V(RF)
V(LO)

17. Active Mixer
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V(IF)
V(RF)
V(LO)
VDD

18. LO: Local Oscillators
 Provide signal to mixer for down conversion or upconversion.
 Implementations:
●Tuned feedback amplifier
●Ring oscillator
●Phase-locked loop (PLL)
●Direct digital synthesizer (DDS)
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19. Phase Splitter
 Splits input signal into two same frequency outputs that differ
in phase by 90 degrees.
 Used for image rejection.
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R
R
C
C
Vin
Vout_1
Vout_2

20. SOC: System-on-a-Chip
 All components of a system are implemented on the same VLSI
chip.
 Requires same technology (usually CMOS) used for all
components.
 Components not implemented on present-day SOC:
●Antenna
●Power amplifier (PA)
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21. SIP: System-in- Package
 Several chips or SOC are included in a package.
 Routing within SIP may be provided via a semiconductor
substrate.
 RF communications system may contain:
■ SIP, containing
● SOC consisting of
 CMOS digital and mixed-signal components (DSP, ADC, DAC)
 CMOS LNA and mixers
 CMOS DDS
 Filters
■ Power amplifier (PA)
■ Antenna
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22. Dimensions of RF Design
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RF
Design
Microwave theory
Communication theory
Random signals
Transceiver architecture
IC design
CAD tools
Wireless standards
Signal propagation

23. RF Design Hexagon
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Noise Power
Frequency
Gain
Linearity
Supply voltage

24. Technologies
 GaAs:
■ High frequency
■ High power
■ Used in PA and front-end switches
■ Low yield, expensive to manufacture
■ Not integrated on silicon chips
 Silicon bipolar and BiCMOS
 Silicon CMOS, suitable for tens of GHz
 SiGe
■ Possible replacement for GaAs
■ Can be integrated on silicon chips
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25. Problem to Solve
 Analyze the function of phase splitting for image rejection in
the following circuit:
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LPF
LPF
90o
+
sin ωLOt
cos ωLOt
RF IF