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Author

Seyed Javad Azhari

Bio: Seyed Javad Azhari is an academic researcher from Iran University of Science and Technology. The author has contributed to research in topics: CMOS & Low voltage. The author has an hindex of 12, co-authored 68 publications receiving 531 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, a new circuit topology based on duality of the well known voltage-mode Wheatstone bridge is described, which can implement ratiometric current measurement which is a vital aspect of current-mode instrumentation and signal processing.
Abstract: This paper describes a new circuit topology based on duality of the well known voltage-mode Wheatstone bridge. This topology can implement ratiometric current measurement which is a vital aspect of current-mode instrumentation and signal processing. The theory of the proposed circuit is developed and its advantages and limitations are discussed. The new circuit (called AZKA cell) may be thought of as the current-mode alternative of traditional voltage-mode Wheatstone bridge. It presents the current-mode circuit designers and engineers their own relevant interface cell. The advantages of the new circuit are stated and some conditioning circuits for its output signal are proposed. Finally, a linearization circuit based on CCII+ is introduced.

50 citations

Journal ArticleDOI
TL;DR: A novel CMIA configuration based on CCII+ is presented, which has acquired further superior qualities such as weaker voltage and current error signals, making it ideal for working with general purpose ICs, higher voltage gains, and much higher CMRR than other topologies.
Abstract: A novel CMIA configuration based on CCII+ is presented. Some of the advantages of this configuration over the traditional Voltage Mode Instrumentation Amplifier (VMIA) are: a wideband differential voltage gain independent of gain magnitude and a high common mode rejection ratio (CMRR) without requiring well-matched resistors. Compared to other previously presented current mode instrumentation amplifiers (CMIAs), each of which showed a limited number of special advantages, this topology benefits from most of those individual advantages, those being: small size, circuit simplicity very inexpensive price, complete circuit symmetry, high voltage gain, and CMRR. In addition, due to the application of the current feedback technique, the topology has acquired further superior qualities such as weaker voltage and current error signals, making it ideal for working with general purpose ICs, higher voltage gains, and much higher CMRR than other topologies. A suggestion is also given to widen the CMRR bandwidth. To prove these advantages and superiorities, a detailed theoretical analysis is given as well as some experiments being performed with AD844AN (the general purpose type) inside a Faraday's cage, with an attenuation better than 60 dB. Both theoretical and experimental investigations are repeated for Wilson and Kaulberg topologies which are claimed to be the best configurations. Results are compared to prove the advantages of the new topology.

50 citations

Journal ArticleDOI
TL;DR: An ultra low voltage, high performance Operational Transconductance Amplifier (OTA) and its application to implement a tunable Gm-C filter and Monte Carlo and temperature dependent simulation results are included to forecast the mismatch and temperature effects after fabrication process.

43 citations

Journal ArticleDOI
TL;DR: A novel ultra-high compliance, low power, very accurate and high output impedance current mirror/source is proposed and its outstanding performance is verified by HSPICE simulation in TSMC 0.18µm CMOS, BSIM3 and Level49 technology.

32 citations

Journal ArticleDOI
TL;DR: Both theoretical and practical investigations proved that both the dc and ac performances of CMRR depend on the matching status of parameters such as C MRR, open-loop gain A, gain-bandwidth product GB, and the output resistance R O of the input op-amps of the CMIA.
Abstract: The common-mode rejection ratio (CMRR) of a power-supply current-sensing current-mode instrumentation amplifier (CMIA) has theoretically been analyzed and formulated. The theory was further investigated by doing experiments using mu A741 and TL071 as op-amps and CA3096 transistors as the current mirrors of the CMIA. Both theoretical and practical investigations proved that both the dc and ac performances of CMRR depend on the matching status of parameters such as CMRR, open-loop gain A, gain-bandwidth product GB, and the output resistance R O of the input op-amps of the CMIA. It has also been shown that, in the CMIA, unlike the voltage-mode instrumentation amplifier, voltage gain is independent of the bandwidth.

25 citations


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01 Jan 2016
TL;DR: The design of analog cmos integrated circuits is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can download it instantly.
Abstract: Thank you for downloading design of analog cmos integrated circuits. Maybe you have knowledge that, people have look hundreds times for their chosen books like this design of analog cmos integrated circuits, but end up in malicious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they juggled with some harmful virus inside their computer. design of analog cmos integrated circuits is available in our book collection an online access to it is set as public so you can download it instantly. Our digital library spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the design of analog cmos integrated circuits is universally compatible with any devices to read.

1,038 citations

Journal ArticleDOI
TL;DR: There are two kinds of tutorial articles: those that provide a primer on an established topic and those that let us in on the ground floor of something of emerging importance.
Abstract: There are two kinds of tutorial articles: those that provide a primer on an established topic and those that let us in on the ground floor of something of emerging importance. The first type of tutorial can have a noted expert who has been gracious (and brave) enough to write a field guide about a particular topic. The other sort of tutorial typically involves researchers who have each been laboring on a topic for some years. Both sorts of tutorial articles are very much desired. But we, as an editorial board for both Systems and Transactions, know that there has been no logical place for them in the AESS until this series was started several years ago. With these tutorials, we hope to continue to give them a home, a welcome, and provide a service to our membership. We do not intend to publish tutorials on a regular basis, but we hope to deliver them once or twice per year. We need and welcome good, useful tutorial articles (both kinds) in relevant AESS areas. If you, the reader, can offer a topic of interest and an author to write about it, please contact us. Self-nominations are welcome, and even more ideal is a suggestion of an article that the editor(s) can solicit. All articles will be reviewed in detail. Criteria on which they will be judged include their clarity of presentation, relevance, and likely audience, and, of course, their correctness and scientific merit. As to the mathematical level, the articles in this issue are a good guide: in each case the author has striven to explain complicated topics in simple-well, tutorial-terms. There should be no (or very little) novel material: the home for archival science is the Transactions Magazine, and submissions that need to be properly peer reviewed would be rerouted there. Likewise, articles that are interesting and descriptive, but lack significant tutorial content, ought more properly be submitted to the Systems Magazine.

955 citations

Journal Article
TL;DR: In this paper, the operation principle, the advantages and disadvantages of each of these techniques, enabling circuit designers to choose the proper design technique based on application requirements, is presented, and three operational transconductance amplifiers (OTA) based on these non-conventional tech- niques are presented, the voltage supply is only ± 0.4 V and the power consumption is 23.5 μW.
Abstract: Designing integrated circuits able to work under low-voltage (LV) low-power (LP) condition is currently undergoing a very considerable boom. Reducing voltage supply and power consumption of integrated circuits is crucial factor since in general it ensures the device reli- ability, prevents overheating of the circuits and in particu- lar prolongs the operation period for battery powered devices. Recently, non-conventional techniques i.e. bulk- driven (BD), floating-gate (FG) and quasi-floating-gate (QFG) techniques have been proposed as powerful ways to reduce the design complexity and push the voltage supply towards threshold voltage of the MOS transistors (MOST). Therefore, this paper presents the operation principle, the advantages and disadvantages of each of these techniques, enabling circuit designers to choose the proper design technique based on application requirements. As an exam- ple of application three operational transconductance amplifiers (OTA) based on these non-conventional tech- niques are presented, the voltage supply is only ±0.4 V and the power consumption is 23.5 μW. PSpice simulation results using the 0.18 μm CMOS technology from TSMC are included to verify the design functionality and corre- spondence with theory.

87 citations

Journal ArticleDOI
TL;DR: A novel current-mode instrumentation amplifier that utilizes an operational floating current conveyor (OFCC) as a basic building block that outperforms existing CMIAs in terms of the number of basic building blocks used, differential gain, and CMRR.
Abstract: This paper presents a novel current-mode instrumentation amplifier (CMIA) that utilizes an operational floating current conveyor (OFCC) as a basic building block. The OFCC, as a current-mode device, shows flexible properties with respect to other current- or voltage-mode circuits. The advantages of the proposed CMIA are threefold. First, it offers a higher differential gain and a bandwidth that is independent of gain, unlike a traditional voltage-mode instrumentation amplifier. Second, it maintains a high common-mode rejection ratio (CMRR) without requiring matched resistors, and finally, the proposed CMIA circuit offers a significant improvement in accuracy compared to other current-mode instrumentation amplifiers based on the current conveyor. The proposed CMIA has been analyzed, simulated, and experimentally tested. The experimental results verify that the proposed CMIA outperforms existing CMIAs in terms of the number of basic building blocks used, differential gain, and CMRR.

86 citations