بسم الله الرحمن الرحيم

1. بسم الله الرحمن الرحيم السلام عليكم و رحمة اللهو بركاته

2. IN THE DIGITAL-ORIENTED ERA, DO WE REALLY NEED ANALOG CIRCUIT DESIGN? Muhammad Taher Abuelma’atti King Fahd University of Petroleum and Minerals Box 203 Dhahran 31261 Saudi Arabia mtaher@kfupm.edu.sa

3. WHAT IS SAID? • Analog design is old fashion and out of date. • Analog design is a kind of classic art in a rapidly changing world of electronics. • The powerful electronic revolution is toward DSP rather than ASP. • It is not wise to select analog design as a career. • It is not wise to select analog design courses. • Analog designers are not considered the heroes of the modern internet and HDTV technology. • Analog design is used only in high voltage area. • The world has gone digital and analog is old.

4. Examples: Digital Camera • Analog chips translate wavelengths and intensities into digital code. • To check the image, the camera retranslate the digital code into a visual display.

5. Examples: Portable Receiver Design Custom Analog IC Custom Digital IC RF Filter Analog Front-End A/D Converter Digital Baseband Processing A “mostly digital” receiver architecture: • “Go digital” at the earliest possible stage

6. RF Filter High Speed A/D Carrier and Timing Sync. RF to Baseband Adaptive Multiuser Detection Analog IC Digital IC Data Out 3.3 Mbps Channel Estimation Receiver Block Diagram

7. Analog RF Design

11. Transceivers

12. Basic Analog Building Blocks: • 1. Amplifiers (Power Amplifiers, Voltage Amplifiers: AF, RF, VF ) • 2. Oscillators (sinusoidal and others) • 3. Filters • 4. Clocks • 5. Analog-to-Digital and Digital-to-Analog Converters. • 6. Modulators (FSK, PSK, ASK, Amplitude, Phase, Frequency Modulation) • 7. Demodulators • 8. Mixers • 9. Phase Locked Loops • 10. Multiplexers. • 11. Duplexers

13. The Reality • No human experiences reality as a pattern of 1’s and 0’s. • The natural world is analog with endlessly variable waves of sound and light, temperature and pressure fluctuations, and shifting magnetic fields. • Digital revolution drives a strong demand for advances in analog electronics.

14. ADVANTAGES OF DIGITAL CIRCUIT DESIGN • Robustness; two signal levels. • Simple and cheap to design; well developed CAD software. • Very suitable for integration. • Offers high precision. • Programmability can be easily obtained. • Easy to design at system level. • Have a cycle/success ratio near unity.

15. ADVANTAGES OF ANALOG CIRCUIT DESIGN • Efficient use of bandwidth. • Simple; no S/H, A/D and D/A. • Lower power consumption; uses fewer transistors. • Low cost; smaller silicon chips. • Power efficient. • Uses physical properties of transistors.

16. WHEN AND WHERE ANALOG CIRCUIT DESIGN IS NEEDED? • To interface a DSP with the input sensors. • To interface a DSP with the output actuators. • In low precision systems; analog neural networks. • In high frequency systems. • In enhancing the performance of digital circuits. On the average, there is probably 15 analog chips needed for every digital processor.

17. ANALOG ENHANCED DIGITAL PERFORMANCE • Enhancing the performance of the hard disk drive; by reshaping distorted high speed digital pulses. • High speed digital circuits are partly analog! Relatively large rise and fall times. • In memory chips and microprocessor chips entire analog blocks; such as amplifiers and PLLs are used. • High frequency clocks.

18. Digital Enhanced Analog Performance • Analog microchip performance can be improved by integrating them with digital monitoring and control circuits. • The line between pure digital and pure analog chips is rapidly blurring, with both incorporating a little bit of the other. • That is Mixed Mode. Experts with feet in both realm are especially valuable.

19. MIXED ANALOG AND DIGITAL CIRCUITS Advantages 1. Reduced system size. 2. Reduced power dissipation. 3. Increased speed of operation. 4. Increased design flexibility. 5. Increased reliability. 6. Reduced system cost.

20. CURRENT RESEARCH IN MAD CIRCUITS A combination of high dynamic range, high speed and acceptable low power dissipation is a challenge for MAD circuits. • Analog neural networks. • Field programmable analog arrays. • Radio frequency circuits. • Analog image processing. • Disk drive electronics. • Fuzzy logic. • Chaotic circuits and systems.

21. WHERE MAD CIRCUITS ARE USED? Almost in every broad application where chips are used. Examples include: • Telecommunications: transmission, reception, switching… • Consumer electronics: audio, video,… • Computers and related equipment: disk drives, LAN transmitters and receivers,.. • Automotive systems: engine control, safety equipment,… • Biomedical instrumentation: hearing aids, cardiac pacemakers,… • Robotics: interfaces to sensors and actuators.

22. FUTURE OF ANALOG • The world around us is essentially analog. • Our senses are organized for communicating with this world. • Analog circuit design is indispensable and irreplacable. • The future of analog circuit design is very dynamic and holds many opportunities. • It takes six to nine months for a college graduate to be productive in digital engineering. • It takes a Ph.D. holder four years to be productive in the analog area.

23. How to Enhance the Image of Analog Circuit Design The lack of interest in analog circuit design could be explained by: • Inadequate teaching of the subject. Only teachers with proven expertise in the area can teach Electronic Circuits courses. • Extensive mathematical manipulations and/or use of the black box approach. This should be minimized and emphasis should be on the physical meaning of the equations. • The lack of understanding of circuits at the voltage and current levels. • Extensive use of simulation and software packages. More emphasis on experimental work is needed. Simulation is not a bad thing, but engineering students must feel the real world. • Wrong advises and the advertising media.

24. CONCLUSION • Analog circuit design is here to stay. Imagine the effect on the digital world of a complete embargo of data converters and signal-conditioning components by the small analog nation. • Analog designers need not leave town.

25. والحمد لله رب العالمين خودا حافظ