Transcript Project Overview
ANALOG DEVICES BEN-GURION UNIVERSITY OF THE NEGEV
Department of Electrical and Computer Engineering
I N T E R D I S C I P L I N A R Y
HARDWARE DESIGN LABORATORY
A fusion of analog and digital research and study
Eugene PAPERNO, Ph.D.
Head, Instrumentation, Circuits, and Devices Track http://www.ee.bgu.ac.il/~paperno Israel, Beer-Sheva, October 2004
RESEARCH DIRECTIONS
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State-retention power gating (SRPG) Ultra low-noise DSP oscillators Electronics for nanotechnology Adaptive magnetic tracking Precise sensors Remote magnetic imaging Integrated HiTc electronics Magnetic shielding
1. State-retention power gating (SRPG)
In the nearest future, increased integration will inevitably increase the power consumption of mobile equipment, such as cellular phones. The power consumption will increase so significantly that the batteries will become discharged within a few tens of minutes. In order to save the power, we suggest a new approach, based on new algorithms and new analog, digital, and mixed circuitry that allows power gating along with immediate restoring the most recent status of the cellular phone hardware.
2. Ultra low-noise DSP oscillators
The aim of this research is to improve the local spectral purity of a DSP-based oscillator by two or even more orders of magnitude compared to that of conventional direct digital synthesis (DDS) oscillators. Namely, our aim is to decrease the harmonics and noise in their vicinity by a factor of >100.
Improving the local spectral purity of oscillators will drastically improve the resolution of many instruments, such as spectrum analyzers, Doppler detectors, sensors, etc., where oscillators serve as heterodynes.
One of the harmonics and noise around it are suppressed Oscillator harmonics and noise
3. Analog electronics for nanotechnology
Many experiments in nanotechnology require ultra-low noise, ultra precise and ultra-stable analog electronic equipment, such as voltage and current references, current drivers, electronic PID and PLL controllers, etc. Commercially available equipment neither meets all the recent needs nor is updated fast enough to follow the fast progress in the field of nanotechnology. A great part of the above equipment is ‘ home made ’ due to cooperation between Physicists and Electrical and Electronics Engineers.
An example of such a cooperation we are involved in is the Atomic Chip project (directed by Professor Folman) aimed at the development of principally new kinds of sensors and components for quantum computers.
ATOMIC CHIP
4. Adaptive magnetic tracking
Magnetic tracking is used more and more widely in bio-medicine, avionics, and automotive applications. We have already developed, built, and tested a principally new DSP-based system for the magnetic tracking of subminiature sensors. The employment of a large transmitting array increases the system accuracy and immunity to retransmitted fields. Our current aim is to make the system smart enough to perform the self-calibration and self-compensation for the fields retransmitted by nearby conducting objects.
LARGE TRANSMITTING ARRAY SENSOR
5. Precise sensors
In cooperation with Kyushu University, Japan, we have developed and tested the most simple and precise solid-state magnetic sensor. Our current aim is to develop new DSP-based algorithms and circuitry that should compensate for sensor ’ s output drift. We assume that the output drift of many types of sensors employing ac bias is caused by the excitation oscillator. The spectrum of the oscillator noise near the fundamental resembles that of 1/
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noise at low frequencies. Being detected, the oscillator noise may turn into the output drift. Discovering the source of the drift should make possible its reduction.
Lock-in amplifier bandwidth
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Noise of the conventional sensor
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New sensor Conventional sensor
Noise of the improved sensor Contribution of the oscillator noise (ac-bias noise) to that of the sensor
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Noise caused by the ac bias
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6. Remote magnetic imaging
The aim of this research is to combine the above sensors in large arrays and to process their outputs in order to locate magnetic dipoles at relatively large distances.
Such systems will detect, for example, weapons or explosives (that include ferromagnetic materials)
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the object approaches the system. Combined with video images, the processed data can clearly reveal, for example, the person carrying a ferromagnetic object and its location.
SURVEILLANCE CAMERA EXPLOSIVE SENSOR ARRAY
7. Integrated HiTc electronics
The aim of this project is to utilize the advantages of HiTc superconducting devices in a new type of hybrid electronic circuits. Namely, we intend to develop ultra-fast and high-power electronic switches that are able to reliably commutate currents of amperes within tens of picoseconds.
ELECTRONICS THIN-FILM HiTc SUPERCONDUCTORS
8. Magnetic shielding
Magnetic shields are an important part of experimental setups in modern fundamental physics, nanotechnology, and instrumentation. Our research in this area is directed at the description and optimization of multilayer cylindrical shields, both closed, open, and partially open. Our aim is to minimize the cost, weight, and size of the shield without too much sacrifice in its shielding factor. In this research, we cooperate with Kyushu University, Japan, and Princeton University, USA.
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