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Articles 61 - 90 of 210

Full-Text Articles in Electronic Devices and Semiconductor Manufacturing

Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi Aug 2013

Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi

Nian X. Sun

This paper reports on the first demonstration of an ultra-miniaturized, high frequency (215 MHz) and high sensitivity MEMS resonant magnetic field sensor based on an AlN/FeGaB bilayer nano-plate resonator capable of detecting magnetic field at nano-Tesla level. Despite of the reduced volume and the high operating frequency of the sensor, high electromechanical performances were achieved (quality factor Q ≈ 511 and electromechanical coupling coefficient kt² ≈ 1.63%). This first prototype was characterized for different magnetic field levels from 0 to 152 Oe showing a frequency sensitivity of ~ 1 Hz/nT and a limit of detection of ~ 10 nT.

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Wireless Transmission Network : A Imagine, Radhey Shyam Meena Engineer, Neeraj Kumar Garg Asst.Prof Apr 2013

Wireless Transmission Network : A Imagine, Radhey Shyam Meena Engineer, Neeraj Kumar Garg Asst.Prof

Radhey Shyam Meena

World cannot be imagined without electrical power. Generally the power is transmitted through transmission networks. This paper describes an original idea to eradicate the hazardous usage of electrical wires which involve lot of confusion in particularly organizing them. Imagine a future in which wireless power transfer is feasible: cell phones, household robots, mp3 players, laptop computers and other portable electronic devices capable of charging themselves without ever being plugged in freeing us from that final ubiquitous power wire. This paper includes the techniques of transmitting power without using wires with an efficiency of about 95% with non-radioactivemethods. In this paper …

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Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi Mar 2013

Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi

Tianxiang Nan

This paper reports on the first demonstration of an ultra-miniaturized, high frequency (215 MHz) and high sensitivity MEMS resonant magnetic field sensor based on an AlN/FeGaB bilayer nano-plate resonator capable of detecting magnetic field at nano-Tesla level. Despite of the reduced volume and the high operating frequency of the sensor, high electromechanical performances were achieved (quality factor Q ≈ 511 and electromechanical coupling coefficient kt² ≈ 1.63%). This first prototype was characterized for different magnetic field levels from 0 to 152 Oe showing a frequency sensitivity of ~ 1 Hz/nT and a limit of detection of ~ 10 nT.

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Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er., Deepa Sharma Mar 2013

Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er., Deepa Sharma

Radhey Shyam Meena

Grid-connected solar PV dramatically changes the load profile of an electric utility customer. The expected widespread adoption of solar generation by customers on the distribution system poses significant challenges to system operators both in transient and steady state operation, from issues including voltage swings, sudden weather-induced changes in generation, and legacy protective devices designed with one-way power flow in mind

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A Shade Tolerant Panel Design For Thin Film Photovoltaics, Sourabh Dongaonkar, Muhammad Alam Mar 2013

A Shade Tolerant Panel Design For Thin Film Photovoltaics, Sourabh Dongaonkar, Muhammad Alam

Sourabh Dongaonkar

We analyze the problem of partial shading of thin film photovoltaic (TFPV) panels, using full two dimensional circuit simulations. By accounting for the panel structure and typical array configurations, we can accurately account for the effect of various shading configurations at the cell and panel level. We demonstrate the limitation of external bypass diodes in protecting shaded cells from reverse breakdown, and explore the whole range of shading scenarios and their impact on reverse stress experienced by shaded cells. Based on the analysis, we identify the key aspects of shading problem, and formulate design rules for shadow aware geometrical design …

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End-To-End Modeling For Variability And Reliability Analysis Of Thin Film Pv, Sourabh Dongaonkar, Muhammad Alam Mar 2013

End-To-End Modeling For Variability And Reliability Analysis Of Thin Film Pv, Sourabh Dongaonkar, Muhammad Alam

Sourabh Dongaonkar

We present an end-to-end modeling framework, spanning the device, module and also system levels, for analyzing thin film photovoltaics (PV). This approach is based on embedding a detailed, statistically relevant, physics based equivalent circuit into module and array level simulations. This approach enables us to analyze key variability and reliability issues in thin film PV, and allows us to interpret their effect on process yield and intrinsic module lifetimes. Our results suggest that the time-zero gap between cell and module efficiencies, a key variability concern for thin-film PV, can be attributed to processrelated shunts with log-normal PDF distributed randomly across …

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Reverse Stress Metastability Of Shunt Current In Cigs Solar Cells, Sourabh Dongaonkar, Erik Sheets, Rakesh Agrawal, Muhammad Alam Mar 2013

Reverse Stress Metastability Of Shunt Current In Cigs Solar Cells, Sourabh Dongaonkar, Erik Sheets, Rakesh Agrawal, Muhammad Alam

Sourabh Dongaonkar

Partial shading in thin film solar panels can result in reverse bias stress across shaded cells. Therefore, it is important to understand the effect of such reverse stress in commercially competitive PV technologies such as CIGS. In this paper, we systematically investigate the effect of moderate reverse bias on solution-processed CIGS solar cells. We subject the solar cells to varying degrees of reverse biases and continuously monitor the impact of the stress on dark current. We also explore the relaxation behavior of dark current following passive storage and the long term effect of the shadow stress on power output of …

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A Physical Model For Non-Ohmic Shunt Conduction And Metastability In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Y, Souvik Mahapatra, Muhammad Alam Mar 2013

A Physical Model For Non-Ohmic Shunt Conduction And Metastability In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Y, Souvik Mahapatra, Muhammad Alam

Sourabh Dongaonkar

We present a physical model of non-ohmic shunt current in a-Si:H p-i-n solar cells, and validate it with detailed measurements. This model is based on space-charge-limited (SCL) transport through localized p-i-p shunt paths, which can arise from contact metal incorporation in a-Si:H layer. This model explains both the electrical characteristics and the metastable switching behavior of the shunts within an integrated framework. We first verify the SCL model using simulations and statistically robust measurements, and then use this picture to analyze our systematic observations of non-volatile switching in these shunts. Our work not only resolves broad experimental observations on shunt …

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On The Nature Of Shunt Leakage In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Y, Dapeng Wang, Michel Frei, Souvik Mahapatra, Muhammad Alam Mar 2013

On The Nature Of Shunt Leakage In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Y, Dapeng Wang, Michel Frei, Souvik Mahapatra, Muhammad Alam

Sourabh Dongaonkar

In this letter, we investigate the nature of shunt leakage currents in large-area (on the order of square centimeters) thin-film a-Si:H p-i-n solar cells and show that it is characterized by following universal features: 1) voltage symmetry; 2) power-law voltage dependence; and 3) weak temperature dependence. The voltage symmetry offers a robust empirical method to isolate the diode current from measured “shunt-contaminated” forward dark IV . We find that space-charge-limited current provides the best qualitative explanation for the observed features of the shunt current. Finally, we discuss the possible physical origin of localized shunt paths in the light of experimental …

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Identification, Characterization, And Implications Of Shadow Degradation In Thin Film Solar Cells, Sourabh Dongaonkar, Karthik Y, Dapeng Wang, Michel Frei, Souvik Mahapatra, Muhammad Alam Mar 2013

Identification, Characterization, And Implications Of Shadow Degradation In Thin Film Solar Cells, Sourabh Dongaonkar, Karthik Y, Dapeng Wang, Michel Frei, Souvik Mahapatra, Muhammad Alam

Sourabh Dongaonkar

We describe a comprehensive study of intrinsicreliability issue arising from partial shadowing of photovoltaicpanels (e.g., a leaf fallen on it, a nearby tree casting a shadow,etc.). This can cause the shaded cells to be reverse biased, causingdark current degradation. In this paper, (1) we calculate thestatistical distribution of reverse bias stress arising from variousshading configurations, (2) identify the components of darkcurrent, and provide a scheme to isolate them, (3) characterizethe effect of reverse stress on the dark current of a-Si:H p-i-ncells, and (4) finally, combine these features of degradationprocess with shadowing statistics, to project ‘shadow-degradation’ (SD) over the operating lifetime …

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Physics And Statistics Of Non-Ohmic Shunt Conduction And Metastability In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Yogendra, Souvik Mahapatra, Muhammad Alam Mar 2013

Physics And Statistics Of Non-Ohmic Shunt Conduction And Metastability In Amorphous Silicon P-I-N Solar Cells, Sourabh Dongaonkar, Karthik Yogendra, Souvik Mahapatra, Muhammad Alam

Sourabh Dongaonkar

In this paper, we present a physical model of the non- Ohmic shunt current ISH in amorphous silicon (a-Si:H) p–i–n solar cells and validate it with detailed measurements. This model is based on space-charge-limited (SCL) transport through localized p–i–p shunt paths. These paths can arise from n-contact metal incorporation in the a-Si:H layer, causing the (n)a-Si:H to be counterdoped to p-type. The model not only explains all the electrical characteristics of preexisting shunts but also provides insight into the metastable switching that is observed in the shunt-dominated region of dark current as well.We first verify the SCL model using simulations …

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Balanced Amplifier Aims For Low Noise, Chin-Leong Lim Feb 2013

Balanced Amplifier Aims For Low Noise, Chin-Leong Lim

Chin-Leong Lim

Cellular basestations' low noise amplifiers (LNA) must have input impedances that are closely matched to the antennas. Unfortunately, the amplifier devices cannot be conjugate matched without sacrificing their noise performances. Current solutions such as the isolator and the balanced LNA can satisfactorily solve the matching problem but at the expense of increased cost, weight and size. On the other hand, the confined space atop cellular towers makes the current solutions unattractive. To shrink the balanced LNA for cellular infrastructure service, we pair a highly integrated dual-amplifier MMIC with miniature multilayer couplers. This MMIC also has the distinction of being the …

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Low Mismatch Uhf Lna For Cellular Infrastructure, Chin-Leong Lim Feb 2013

Low Mismatch Uhf Lna For Cellular Infrastructure, Chin-Leong Lim

Chin-Leong Lim

Cellular basestations' low noise amplifiers (LNA) must have input impedances that are closely matched to the antennas. Unfortunately, the amplifier devices cannot be conjugate matched without sacrificing their noise performances. Current solutions such as the isolator and the balanced LNA can satisfactorily solve the matching problem but at the expense of increased cost, weight and size. On the other hand, the confined space atop cellular towers makes the current solutions unattractive. To shrink the balanced LNA for cellular infrastructure service, we pair a highly integrated dual-amplifier MMIC with miniature multilayer couplers. This MMIC also achieves the distinction of being the …

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Novel Three-Phase Asymmetrical Cascaded Multilevel Voltage Source Inverter, Saad Mekhilef Feb 2013

Novel Three-Phase Asymmetrical Cascaded Multilevel Voltage Source Inverter, Saad Mekhilef

Saad Mekhilef

Series connection of power cells in asymmetrical cascaded configurations helps to cancel redundant output levels and maximise the number of different levels generated by the inverter. A new configuration of three-phase multilevel asymmetrical cascaded voltage source inverter is presented. This structure consists of series-connected sub-multilevel inverters blocks. The number of utilised switches, insulated gate driver circuits, voltage standing on switches, installation area and cost are considerably reduced. Cascaded-cell DC voltages in each inverter leg form an arithmetic sequence with common difference of E. With the selected inverter DC sources, high-frequency pulse-width modulation (PWM) control methods can be effectively applied without …

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Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi Feb 2013

Mems Resonant Magnetic Field Sensor Based On An Aln/Fegab Bilayer Nano-Plate Resonator, Yu Hui, Tianxiang Nan, Nian Sun, Matteo Rinaldi

Matteo Rinaldi

This paper reports on the first demonstration of an ultra-miniaturized, high frequency (215 MHz) and high sensitivity MEMS resonant magnetic field sensor based on an AlN/FeGaB bilayer nano-plate resonator capable of detecting magnetic field at nano-Tesla level. Despite of the reduced volume and the high operating frequency of the sensor, high electromechanical performances were achieved (quality factor Q ≈ 511 and electromechanical coupling coefficient kt² ≈ 1.63%). This first prototype was characterized for different magnetic field levels from 0 to 152 Oe showing a frequency sensitivity of ~ 1 Hz/nT and a limit of detection of ~ 10 nT.

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Ultra-Fast And High Resolution Nems Thermal Detector Based On A Nano-Air-Gap Piezoelectric Resonant Structure, Yu Hui, Matteo Rinaldi Feb 2013

Ultra-Fast And High Resolution Nems Thermal Detector Based On A Nano-Air-Gap Piezoelectric Resonant Structure, Yu Hui, Matteo Rinaldi

Matteo Rinaldi

This paper presents the theoretical modeling and experimental verification of an innovative Nano Electro Mechanical System (NEMS) technology suitable for the implementation of ultra-fast and high resolution un-cooled thermal detectors. Fundamental challenges associated to the implementation of mechanically resonant thermal detectors are overcome with the introduction of an innovative technology platform in which a temperature sensitive Aluminum Nitride (AlN) nano-plate resonator and a monolithically integrated micromachined suspended heat absorbing element are perfectly overlapped but separated by a sub-micron air gap. By placing the absorbing element outside the body of the resonator (but suspended over it) the electromechanical performance of the …

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Ultra-Thin-Film Aln Contour-Mode Resonators For Sensing Applications, Matteo Rinaldi, Chiara Zuniga, Gianluca Piazza Feb 2013

Ultra-Thin-Film Aln Contour-Mode Resonators For Sensing Applications, Matteo Rinaldi, Chiara Zuniga, Gianluca Piazza

Matteo Rinaldi

This paper reports on the design and experimental verification of a new class of ultra-thin-film (250 nm) aluminum nitride (AlN) microelectromechanical system (MEMS) contour mode resonators (CMRs) suitable for the fabrication of ultra-sensitive gravimetric sensors. The device thickness was opportunely scaled in order to increase the mass sensitivity, while keeping a constant frequency of operation. In this first demonstration the resonance frequency of the device was set to 178 MHz and a mass sensitivity as high as 38.96 KHz⋅μm2/fg was attained. This device demonstrates the unique capability of the CMR-S technology to decouple resonance frequency from mass sensitivity.

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Aln Contour-Mode Resonators For Narrow-Band Filters Above 3 Ghz, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza Feb 2013

Aln Contour-Mode Resonators For Narrow-Band Filters Above 3 Ghz, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza

Matteo Rinaldi

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) super high frequency (SHF) laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions in order to excite a contour-extensional mode of vibration in nano features of an ultra-thin (250 nm) aluminum nitride (AlN) film. In this first demonstration two-port resonators vibrating up to 4.5 GHz were fabricated on the same die and attained electromechanical coupling, kt^2, in excess of …

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Ultra-Thin Super High Frequency Two-Port Aln Contour-Mode Resonators And Filters, Matteo Rinaldi, Chiara Zuniga, Chnegjie Zuo, Gianluca Piazza Feb 2013

Ultra-Thin Super High Frequency Two-Port Aln Contour-Mode Resonators And Filters, Matteo Rinaldi, Chiara Zuniga, Chnegjie Zuo, Gianluca Piazza

Matteo Rinaldi

This paper reports on the demonstration of a new class of ultra-thin (250 nm thick) super high frequency (SHF) AlN piezoelectric two-port resonators and filters. A thickness field excitation scheme was employed to excite a higher order contour extensional mode of vibration in an AlN nano plate (250 nm thick) above 3 GHz and synthesize a 1.96 GHz narrow-bandwidth channel-select filter. The devices of this work are able to operate over a frequency range from 1.9 to 3.5 GHz and are employed to synthesize the highest frequency MEMS filter based on electrically self-coupled AlN contour-mode resonators. Very narrow bandwidth (~ …

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5-10 Ghz Aln Contour-Mode Nanoelectromechanical Resonators, Matteo Rinaldi, Chiara Zuniga, Gianluca Piazza Feb 2013

5-10 Ghz Aln Contour-Mode Nanoelectromechanical Resonators, Matteo Rinaldi, Chiara Zuniga, Gianluca Piazza

Matteo Rinaldi

This paper reports on the design and experimental verification of Super High Frequency (SHF) laterally vibrating NanoElctroMechanical (NEMS) resonators. For the first time, AlN piezoelectric nanoresonators with multiple frequencies of operation ranging between 5 and 10 GHz have been fabricated on the same chip and attained the highest f-Q product (4.6E12 Hz) ever reported in AlN contour-mode devices. These piezoelectric NEMS resonators are the first of their class to demonstrate on-chip sensing and actuation of nanostructures without the need of cumbersome or power consuming excitation and readout systems. Effective piezoelectric activity has been demonstrated in thin AlN films having vertical …

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Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Feb 2013

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also …

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Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza Feb 2013

Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza

Matteo Rinaldi

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) superhigh- frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contourextensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt^2, in excess of 1.5%. These devices are employed to …

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Cause And Prevention Of Moisture-Induced Degradation Of Resistance Random Access Memory Nanodevices, Albert Chen Jan 2013

Cause And Prevention Of Moisture-Induced Degradation Of Resistance Random Access Memory Nanodevices, Albert Chen

Albert B Chen

Dielectric thin films in nanodevices may absorb moisture, leading to physical changes and property/performance degradation, such as altered data storage and readout in resistance random access memory. Here we demonstrate using a nanometallic memory that such degradation proceeds via nanoporosity, which facilitates water wetting in otherwise nonwetting dielectrics. Electric degradation only occurs when the device is in the charge-storage state, which provides a nanoscale dielectrophoretic force directing H2O to internal field centers (sites of trapped charge) to enable bond rupture and charged hydroxyl formation. While these processes are dramatically enhanced by an external DC or AC field and electron-donating electrodes, …

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Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er. Jan 2013

Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er.

Radhey Shyam Meena

As solar photovoltaic power generation becomes more commonplace, the inherent intermittency of the solar resource poses one of the great challenges to those who would design and implement the next generation smart grid. Specifically, grid-tied solar power generation is a distributed resource whose output can change extremely rapidly, resulting in many issues for the distribution system operator with a large quantity of installed photovoltaic devices. Battery energy storage systems are increasingly being used to help integrate solar power into the grid. These systems are capable of absorbing and delivering both real and reactive power with sub-second response times. With these …

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Demonstration And Modeling Of Multi-Bit Resistance Random Access Memory, Albert Chen Dec 2012

Demonstration And Modeling Of Multi-Bit Resistance Random Access Memory, Albert Chen

Albert B Chen

Although intermediates resistance states are common in resistance random access memory (RRAM), two-way switching among them has not been demonstrated. Using a nanometallic bipolar RRAM, we have illustrated a general scheme for writing/rewriting multi-bit memory using voltage pulses. Stability conditions for accessing intermediate states have also been determined in terms of a state distribution function and the weight of serial load resistance. A multi-bit memory is shown to realize considerable space saving at a modest decrease of switching speed.

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Z-Source Inverter For Automotive Applications, Omar Ellabban, Joeri Van Mierlo Dec 2012

Z-Source Inverter For Automotive Applications, Omar Ellabban, Joeri Van Mierlo

Omar Ellabban

No abstract provided.

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Capacitor Voltage Control Techniques Of The Z-Source Inverter: A Comparative Study, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire Dec 2012

Capacitor Voltage Control Techniques Of The Z-Source Inverter: A Comparative Study, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire

Omar Ellabban

The Z-source inverter (ZSI) is a recently proposed single-stage power conversion topology. It adds voltage boost capability for complementing the usual voltage buck operation of a traditional voltage source inverter (VSI) with improved reliability. In this paper, a single-loop and dual-loop capacitor voltage control techniques for the ZSI are digitally designed based on a third order small signal model of the ZSI, implemented using a digital signal processor (DSP) and compared. Simulation and experimental results of a 30 kW ZSI during input voltage changes, load disturbances and steady state operations are presented and compared. The results show that the dual-loop …

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Multi-Hole Waveguide Directional Couplers, Mahmoud Moghavvemi, Hossein Ameri Mahabadi, Farhang Alijani Nov 2012

Multi-Hole Waveguide Directional Couplers, Mahmoud Moghavvemi, Hossein Ameri Mahabadi, Farhang Alijani

Hossein Ameri Mahabadi

1. Introduction The directional couplers are inherently assumed as four-port devices, which consisted of two transmission lines that are electromagnetically coupled to each other. The first port is named as input, and the second one as output or transmitted, the third one as sampling or coupled and the fourth one as isolated or terminated. By using a special design the input power is divided between output and coupled port in a certain ratio named coupling factor. The required value for coupling factor P1/P3 defines the range of applications for directional couplers. Based on the application, coupling factor could be any …

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Recovery Time Of The Schottky-Pin Limiter, Chin-Leong Lim Oct 2012

Recovery Time Of The Schottky-Pin Limiter, Chin-Leong Lim

Chin-Leong Lim

The Schottky-PIN limiter has a ~8dB lower limiting threshold than the self-biased PIN limiter. Following the cessation of overdrive, the limiter requires some time to return to a low-loss state. This transitory state, which is known as the recovery time or blind/dead time, disrupts communication and causes information loss. Unlike the self-biased PIN limiter, there is a dearth of information pertaining to the recovery time of the PIN-Schottky limiter. This work characterizes the most popular form of the PIN-Schottky limiter and also proposes a simple modification to speed up its recovery time. We measured recovery times of >2000uS and 130uS …

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Reduce Losses In Rf Schottky-Pin Limiter Circuits, Chin-Leong Lim Oct 2012

Reduce Losses In Rf Schottky-Pin Limiter Circuits, Chin-Leong Lim

Chin-Leong Lim

Limiters can protect wireless receivers from physical damage and information loss. The Schottky-PIN limiter is especially protective because its limiting threshold is ~10dB lower than that of the self-biased PIN limiter. Unfortunately, the limiter diodes have parasitic capacitances that create insertion loss. Moreover, the extra diode in the Schottky-PIN limiter increases its loss over that of the PIN diode-only limiter. Techniques to minimize the parasitic capacitances include using bare chip, air cavity packaging, diode stacking, mesa construction, isolating the Schottky diode from the signal path and connecting the diodes to a low impedance node. But the aforementioned techniques either sacrifice …

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