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A milling cutter with large length–diameter ratio has been essential in machining structural parts with deep cavity and deep hole features. However, chatter vibration is apt to occur with the increase of tool overhang. A damped milling cutter is developed by employing a single-degree-of-freedom passive damper located inside the arbor. The stiffness and damping design of the embedded damper are carried out by following the equal peaks criterion. A novel design is fulfilled to avoid the disequilibrium of the cutter during high-speed rotation, and an accurate experimental tuning of the design parameters is required to achieve the optimum vibration suppression due to a low mass ratio of 2.5%. Modal analysis demonstrates that the damped cutter with an approximate length–diameter ratio of 8 can reach 75% magnitude reduction at all orientations, which is benefical to resist milling force excitation varying with the rotation angle. Chatter stability simulation demonstrates that the damped cutter is able to increase the stability limits based on the evaluation of undamped and Sandvik cutters. Three configurations of machining tests are carried out and the design of the damped cutter is validated by the machining audio signals and machined surface roughness in the end. [ABSTRACT FROM AUTHOR]

A 300-MHz class-E dc–dc converter using the resonant gate driving technique is proposed. The gate driver utilizes the harmonic shaping network and RC feedback to enhance the output swing voltage, and the class-E power converter can minimize the voltage–current overlap to improve efficiency. With the $0.\text{25-}{\mu} {\text{m}}$ GaN high-electron-mobility transistor and $\text{0.18-}{\mu} {\text{m}}$ CMOS for the switching power device and the gate driver, respectively, a complete dc–dc converter operating at 300 MHz is demonstrated including all the passive components microfabricated by integrated passive device (IPD) technology on the high-resistivity silicon substrate. The overall chip area is smaller than 1 cm × 1 cm and the volume is only 0.115 cm3. The measured results show a maximum output power of 4.16 W with 47.3% efficiency. An excellent power density of 36.2 W/cm3 can be achieved. The flip-chip assembled converter on the IPD substrate demonstrates the potential of heterogeneous integration for high-frequency power conversion applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel concrete-temperature monitoring method using an embedded passive wireless sensor. After introducing the control method of concrete-temperature monitoring, this work proposes an embedded passive wireless sensor based on radio frequency identification (RFID) technology. It includes a microstrip antenna specially designed for embedded monitoring due to its round plane architecture. The proposed wireless sensor consists of three parts: an energy management section, a digital section and an RFID section. Laboratory experimentation and on-site testing demonstrate that, despite the high losses of concrete, the proposed sensor tag provides reliable communication performance in passive mode. The maximum reader-tag communication distance is 7 m at 915 MHz, and the measured results are highly consistent with the results measured by thermocouple. To the knowledge of the authors, this work is the first to use the RFID sensor tag to measure concrete temperature. [ABSTRACT FROM AUTHOR]

Abstract: This letter presents a low‐loss and highly‐selective differential bandpass filter (BPF) with high common‐mode rejection ratio (CMRR). The presented integrated passive device process provides high quality lumped elements, and therefore a low insertion loss of the BPF can be obtained. The circuit also uses series‐shunt resonators for controlling its differential‐ and common‐mode transmission zeros. Moreover, with a proper choice of circuit component values, a high common‐mode rejection can be controlled at a specific frequency without alternating properties of the filter. The chip area of the filter is 3.74 mm2 including all testing pads. Additionally, the differential BPF achieves a 1.5‐dB insertion loss and 11‐dB return loss with a 73% 3‐dB bandwidth at 2.2 GHz. Finally, the peak CMRR at the frequency of interest is up to 50 dB. [ABSTRACT FROM AUTHOR]

Electronic devices are shrinking day by day, while the speed and reliability is increasing. At the same time, IC designs and micro/nano electronic systems are becoming extremely complex with billions of components squeezed into a small area of silicon. Due to increase in functionality and decrease in size, number of components have increased on small area in IC and PWB. The use of passive components like capacitors, resistors and inductors is also increasing with time. The old surface mounted passive components occupy more area. The solution is to embed passive components inside the substrate, thereby decreasing the size. In the new technology, embedding passive components inside the substrate of the chip and the PWB results in an improvement in the reliability factor and at the same time improves the electrical performance. [ABSTRACT FROM AUTHOR]

In this paper, a set of ultra-compact CMOS bandpass filters are proposed for ultra-wideband (UWB) applications. For this aim, a comparative study was first performed enabling to deduce that Chebyshev-inverse and Hourglass filtering functions can be the most suitable for UWB operation. The impact of the latter functions on the easiness of implementation in integrated passive device (IPD) technologies and filtering performance was investigated, where the designed filters were implemented in 0.18-µm CMOS technology. Finally, the issue of in-band interference has been addressed by rejecting the wireless local area network (WLAN) signals. The performance of the proposed UWB filters were validated through post layout simulation, and good fulfilling with UWB specifications was noted while depicting a compact size, smaller than 0.6 mm 2 , which is very miniaturised compared with relevant works mentioned in the state of the art. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to investigate the behavior of embedded passives under changing temperature conditions. Influence of different temperature changes on the basic properties of embedded passives was analyzed. The main reason for these investigations was to determine functionality of passives for space application.Design/methodology/approach The investigations were based on the thin-film resistors made of Ni-P alloy, thick-film resistors made of carbon or carbon-silver inks, embedded capacitors made of FaradFlex materials and embedded inductor made in various configurations. Prepared samples were examined under the influence of a constant elevated temperature (100, 130 or 160°C) in a long period of time (minimum of 30 h), thermal cycles (from −40 to +85°C) or thermal shocks (from −40 to +105°C or from −40 to +125°C).Findings The achieved results revealed that resistance drift became bigger when the samples were treated at a higher constant temperature. At the same time, no significant difference in change in electrical properties for 50 and 100 Ω resistors was noticed. For all the tests, resistance change was below 2 per cent regardless of a value of the tested resistors. Conducted thermal shock studies indicate that thin-film resistors, coils and some thick-film resistors are characterized by minor variations in basic parameters. Some of the inks may show considerable resistance variations with temperature changes. Significant changes were also exhibited by embedded capacitors.Originality/value The knowledge about the behavior of the operating parameters of embedded components considering environmental conditions allow for development of more complex systems with integrated printed circuit boards. [ABSTRACT FROM AUTHOR]

In this paper, a GaAs absorptive single-pole double-throw (SPDT) RF switch and its application to a 2.4-GHz switched beamformer module are presented. The proposed absorptive SPDT RF switch features low-power consumption and low insertion loss with good output matching both in the on and off states. Specifically, the measured insertion loss in the on state is less than 1 dB, and the measured input and output return losses are both better than 11.2 dB from 1.9 to 2.6 GHz. The measured output return loss in the off state is better than 15 dB, and the measured isolation is better than 24.7 dB in the same frequency range. Two proposed absorptive SPDT switches are then employed to form an absorptive single-pole four-throw RF switch, and it is integrated with a miniaturized $4 \times 4$ Butler matrix using the integrated passive device (IPD) technology to achieve a compact 2.4-GHz switched beamformer module with a very low profile. Specifically, the module size is 4.9 mm $\times5$ mm with a thickness of only 0.4 mm. The IPD beamformer module is then used to realize a low-profile 2-D scanning antenna array, and 16 different beams in azimuth and elevation dimensions are successfully generated. [ABSTRACT FROM PUBLISHER]

This paper presents the modeling, design, fabrication, and characterization of an innovative and miniaturized thin-film bandpass filter with coupled spiral structures in ultrathin glass substrates (30– 100~\mu \textm ). This filter is demonstrated for two applications: 3-D integrated passive devices and embedded thinfilm filters in RF modules. A compact filter design was achieved through an integrated resonant structure that effectively utilizes the inductive and capacitive coupling between metal layers on either side of an ultrathin glass substrate or organic build-up layer. The designed filters (layout area <1 mm2 with 80– 150~\mu \textm device thickness) were fabricated on a 30- \mu \textm -thin glass substrate using a panel-based low-cost approach with double-side thin-film wiring processes. The effect of process variations on the performance of the proposed structures was also studied. Furthermore, an improved WLAN filter is designed and demonstrated by employing specific structural modifications. The measured frequency response of the filters shows good model-to-hardware correlation, with very low insertion loss (0.6 dB) in the passband, and high adjacent-band rejection (>25 dB). [ABSTRACT FROM PUBLISHER]

An innovative integrated passive safety system for a research reactor is proposed in this study to improve the safety of the research reactor. This integrated system has three functions in the facility as a decay tank, siphon breaker, and long-term cooling tank. This paper also deals with the process of designing and optimizing the decay tank and the siphon breaker of the integrated passive safety system. At first, the decay tank was designed and improved step by step, while considering the computational fluid dynamics analysis results. Consequently, we could satisfy the design requirements of the decay tank. In addition, the performance of a new type of siphon breaker that was installed in the final decay tank model was tested. We designed an 18-inch diameter siphon breaker at the top of the decay tank’s third section, and we could observe the breaking of the siphon that prevented the occurrence of a severe accident in the research reactor. By locating the siphon breaker at the third section of the decay tank, we could also use the coolant of the front three sections for long-term cooling of the research reactor. [ABSTRACT FROM AUTHOR]

A diplexer offering the advantages of compact size, high performance, and high reliability is proposed on the basis of advanced integrated passive device (IPD) fabrication techniques. The proposed diplexer is developed by combining a third-order low-pass filter (LPF) and a third-order high-pass filter (HPF), which are designed on the basis of the elliptic function prototype low-pass filter. Primary components, such as inductors and capacitors, are designed and fabricated with high Q-factor and appropriate values, and they are subsequently used to construct a compact diplexer having a chip area of 900 μm × 1100 μm (0.009 λ 0 × 0.011 λ 0 , where λ 0 is the guided wavelength). In addition, a small-outline transistor (SOT-6) packaging method is adopted, and reliability tests (including temperature, humidity, vibration, and pressure) are conducted to guarantee long-term stability and commercial success. The packaged measurement results indicate excellent RF performance with insertion losses of 1.39 dB and 0.75 dB at operation bands of 0.9 GHz and 1.8 GHz, respectively. The return loss is lower than 10 dB from 0.5 GHz to 4.0 GHz, while the isolation is higher than 15 dB from 0.5 GHz to 3.0 GHz. Thus, it can be concluded that the proposed SOT-6 packaged diplexer is a promising candidate for GSM/CDMA applications. Synthetic solution of diplexer design, RF performance optimization, fabrication process, packaging, RF response measurement, and reliability test is particularly explained and analyzed in this work. [ABSTRACT FROM AUTHOR]

Recently, integrated passive devices have become increasingly popular; inductor realization, in particular, offers interesting high performance for RF modules and systems. In this paper, a development of differential inductor fabricated by integrated passive devices technology using a double air-bridge structure is presented. A study of the model development of the differential inductor is first demonstrated. In this model section, a segment box analysis method is applied to provide a clear presentation of the differential inductor. Compared with other work that only shows a brief description of the process, the integrated passive devices process used to fabricate the inductor in this study is elaborated on. Finally, a characterization of differential inductors with different physical layout parameters is illustrated based on inductance and quality factors, which provides a valuable reference for realizing high performance. The proposed work provides a good solution for the design, fabrication and practical application of RF modules and systems. [ABSTRACT FROM AUTHOR]

We present a concept for the characterization of micro-fabricated based resonator incorporating air-bridge metal-insulator-semiconductor (MIS) capacitor to continuously monitor an individual's state of glucose levels based on frequency variation. The investigation revealed that, the micro-resonator based on MIS capacitor holds considerable promise for implementation and recognition as a glucose sensor for human serum. The discrepancy in complex permittivity as a result of enhanced capacitor was achieved for the detection and determination of random glucose concentration levels using a unique variation of capacitor that indeed results in an adequate variation of the resonance frequency. Moreover, the design and development of micro-resonator with enhanced MIS capacitor generate a resolution of 112.38 × 10 −3 pF/mg/dl, minimum detectable glucose level of 7.45 mg/dl, and a limit of quantification of 22.58 mg/dl. Additionally, this unique approach offers long-term reliability for mediator-free glucose sensing with a relative standard deviation of less than 0.5%. [ABSTRACT FROM AUTHOR]

This paper presents a summary of an experimental investigation and the derivation of a bond-slip model for reinforcing steel embedded in moderately confined concrete under monotonic and cyclic loadings. Moderately confined concrete encompasses the domain between unconfined and well-confined concrete, the limits of which are defined in the paper. The proposed constitutive law adapts and extends the well-known Eligehausen-Filippou model for well-confined concrete to moderately confined concrete. It is described by an envelope curve and degradation rules. The former is obtained through a confinement index, defined in this study as a function of the amount of confining steel and concrete, distance between confining steel and the rebar, and concrete segregation effect. It is proposed to adopt the same degradation rules used for well-confined concrete. These rules are validated through statistical tests for moderately confined concrete. They are found to predict correctly the main features of reduced envelope response under increasing cycling amplitudes but to underestimate response degradation under constant cycling limits for the subsequent cycles to the first cycle. To demonstrate the validity and limitations of the proposed model, its predictions under monotonic loading are compared with experimental results and analytical predictions from other studies. [ABSTRACT FROM AUTHOR]

A novel silicon-based suspended MIM capacitor fabrication technique combining thin-film and bulk silicon etching technologies with high-quality factor is presented. The influence of low resistive silicon on the parasitics of integrated capacitors is analyzed by EM simulation. The suspended structure is achieved and optimized by a two-step back-etching process. The Q factor of the 3.3 pF suspended MIM capacitor at 2 GHz is about 79 % larger than the non-suspended one and the Q is increased from 46.8 to 61.9, respectively. And a ten-element π equivalent model including electrode and substrate parasitics as well as dielectric loss is used to fit the suspended MIM capacitors well up to 10 GHz, demonstrating that the suspended MIM capacitors exhibit both lower substrate loss and lower parasitic capacitance of the substrate. [ABSTRACT FROM AUTHOR]

In this paper, an ultrabroadband two-way power divider with super compact circuit size is demonstrated using the silicon-based integrated passive device technology. By replacing all the eight quarter-wavelength lines in a conventional four-section Wilkinson power divider with bridged-T coils, the circuit size can be largely reduced without reducing the bandwidth. As a result, an ultrabroadband power divider with 10-dB return loss/isolation bandwidth from 1.85 to 21.30 GHz can be realized in a very compact circuit size of 3.41 \times 1.17 mm2, which is only about 0.132\lambda _{0}\times 0.045\lambda _{\mathrm {\mathbf {0}}} at the center frequency f_{0} = 11.6$ GHz. The measured insertion loss is less than 2 dB in the same frequency range. To the best of our knowledge, this is the smallest ultrabroadband passive power divider design with larger than 10:1 bandwidth ever reported. [ABSTRACT FROM PUBLISHER]

A novel on-chip measurement technique for characterizing conducted electromagnetic emission of integrated circuits in the gigahertz frequency range is proposed. The International Electrotechnical Commission (IEC) direct coupling method is reviewed, and the considerations on improving the applicable bandwidth of the testing probes are discussed. Design of the most critical resistive components for the probes is elaborated to achieve the required accuracy and bandwidth. With the compact chip probes realized by the integrated passive device (IPD) technology, the measurement bandwidth can be significantly extended compared with the conventionally used surface mounted device resistors. The probes are verified to comply with the IEC 61967-4 standard, and an excellent bandwidth up to 15 GHz can be achieved. By connecting the flipped die under test with the probes embedded in IPD substrate (core sizes of the 1- \Omega current probe and 150- \Omega voltage probe are 0.55~\text mm\times 0.77 mm and 0.83~\text mm\times 1.49 mm, respectively), the conducted emission measurement of a 58-MHz oscillator integrated circuit is demonstrated up to 3 GHz. [ABSTRACT FROM PUBLISHER]

This study presents a switchable bandpass circuit using a standard 0.18 μm complementary metal-oxide semiconductor (CMOS) and an integrated passive device (IPD) technology for fifth-generation (5G) mobile communications. The circuit consists of two IPD bandpass filters (BPFs) and one CMOS single-pole-double-throw switch for the 28 or 39 GHz bands. The broadband switch uses a body-float resistor to improve its insertion loss and power-handling capability. Moreover, the two rectangular ring BPFs not only achieve low losses but also feature good out-of-band rejections. The CMOS chip is then packaged on the IPD substrate with a footprint area of 5.4 mm2. The switchable filter results in 4.5/4.7 dB insertion loss, better than 35/30.1 dB isolation, and 18.5/17 dBm input P1 dB. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a high-efficiency power amplifier using quasi-MMIC technology. The efficiency enhancement is achieved based upon the second or third harmonic control provided by input and output matching networks. The gate-source voltage waveform control with Class-F operation achieves significant efficiency improvements. The quasi-MMIC technology using silicon-integrated passive devices (Si-IPDs) can drive the solution to provide compact size at 2.4 GHz. The output matching network for Class-F operation is described, using lumped elements to reduce circuit size. The dimensions of the fabricated power amplifier are 3.6 mm × 7.6 mm, with a thickness of 0.15 mm. The measured results show that the power amplifier has a small signal gain of about 10 dB and a Psat of 41.8 dBm with a maximum drain efficiency of 70.8% at 2.4 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2178-2182, 2016 [ABSTRACT FROM AUTHOR]

In this paper, new 3-dB quadrature couplers based on the two-layered edge-coupling mechanism are designed and implemented in the printed circuit board (PCB) and silicon-based integrated passive device (IPD) technologies. To achieve strong edge-coupling, the proposed coupler consists of two sets of parallel-connected lines, which are placed on the top and bottom metallic layers of the substrate slab, respectively. The design concept and procedures are first exemplified by implementing a 3-dB coupler in the PCB technology at 2 GHz. In addition, since the proposed circuit structure avoids using bonding wires or air bridges, it has the advantage of applying in the millimeter-wave range. However, as the proposed coupler designed in the multilayered IPD substrate, it will lead to an obvious phase velocity difference between two orthogonal modes, $c$ - and $\pi $ -mode waves. To compensate this phenomenon, two millimeter-wave IPD couplers with different slow-wave structures are proposed, designed, and experimentally verified at 38 GHz. [ABSTRACT FROM AUTHOR]

ABSTRACT This letter reports a new implementation of miniaturized wideband bandstop (WBBS) filter using a gallium-arsenide (GaAs)-based integrated passive device technology (IPD). The implementation of an air-bridge capacitor explores the possibility of frequency selectivity from 8.15 to 9.20 GHz. The WBBS filter generates a return loss of −0.50 dB with a rejection depth of −38.01 dB at the resonance frequency of 9.20 GHz. The size of the filter was drastically reduced by implementing a microfabrication (IPD) with folded meandered-line, featuring the length equal to 0.38 times the guided wavelength (λg) that occupies only 0.22 λg × 0.13 λg of the die area. The selectivity of the filter was reflected by the higher value of return loss with sufficient suppression of out-of-band signals close to the resonance frequency. Experimental verification of the filter response demonstrates its potential as a WBBS filter operating in the X-band frequency spectrum. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:980-985, 2016 [ABSTRACT FROM AUTHOR]

The thin film integrated passive device (IPD) has caused intensively attention due to its high integrated level and application in System in Package (SiP). Meanwhile, the IPD filter has shown great application value in modern wireless communication system. In this paper, the design method of a compact silicon-based lumped IPD band-pass filter with two tunable finite transmission zeros is shown. The passband of the designed filter is 2.4–2.5 GHz. Specific schematic is used to introduce two independently tunable transmission zeros. The specific schematic contains mutual inductor structure, which is realized by making two planar spiral inductors to partially overlap with each other and is helpful to decrease the size of the filter. The mutual inductance is adjustable by changing the overlap degree. To design and optimize the layout of the filter more efficiently, the schematic-layout mutual feedback method is presented. Finally, the measurement results verify the validity of the whole design process and method. The size of the designed second-order band-pass filter is 0.85 mm×0.85 mm×0.35 mm. To the best of our knowledge, the band-pass-filter developed in this paper has the smallest size while achieving equivalent electrical performance. [ABSTRACT FROM AUTHOR]

Let α be a contact form on a manifold M, and L ⊆ M a closed Legendrian submanifold. I prove that L intersects some characteristic for α at least twice if all characteristics are closed and of the same period, and α embeds nicely into the product of R2n and an exact symplectic manifold. As an application of the method of proof, the minimal action of a regular closed coisotropic submanifold of complex projective space is at most π/2. This yields an obstruction to presymplectic embeddings, and in particular to Lagrangian embeddings. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a design approach of a band-pass filter which is fabricated on an integrated passive device process and is capable of operating over the unlicensed 60-GHz band (57-64 GHz). The band-pass filter proposed in this article evolves from a typical one comprising two identical, mirrored open-loop half-wavelength microstrip line resonators. The experimental results demonstrate an insertion loss of less than 2.4 dB, a return loss of better than 10 dB over the 60-GHz band, and a 3-dB bandwidth of 24 GHz (∼42%). The simulation and measurement results are well matched up to 110 GHz. This filter is suited for system-in-a-package V-band front-end systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:199-202, 2016 [ABSTRACT FROM AUTHOR]

This paper presents a low-phase-noise and wide-tuning-range voltage-controlled oscillator (VCO) implemented in a standard 0.18- \mu \textm complementary metal-oxide–semiconductor (CMOS) process with an integrated passive device (IPD) transformer. Even- and odd-mode oscillations of the transformer-based resonator can be achieved by the mode-switching topology, and the oscillations in the two modes result in a wide tuning range of the VCO. Moreover, the IPD-based transformer achieves high-quality ( $Q$ ) factors ( Q >30$ ), which is impractical in standard CMOS-based technologies due to their lossy silicon substrate. The high- Q$ IPD transformer reduces the phase noise of the VCO and, therefore, leads to a superior figure-of-merit (FOM) and FOM including the tuning range ( ). Operating at 0.8 V supply voltage, the VCO consumes 9.2-mW dc power. At this bias condition, the measured phase noise is −124.2 dBc/Hz at 1-MHz offset from the 6.26-GHz oscillation frequency. Furthermore, the VCO exhibits a 65.7% tuning range and the flipped CMOS chip is packaged on the IPD substrate with a footprint area of 4.35 mm2. Compared with previously published CMOS-based VCOs, the presented VCO features excellent performances in phase noise, wide tuning range, FOM, and \mathrm {FOM}_{T} . [ABSTRACT FROM AUTHOR]

In this paper, an accurate wideband modeling approach based on a cylindrical mode expansion of electromagnetic filed around perfect magnetic conductors (PMCs) is proposed to analyze the electrical properties of high-density through glass via (TGV) arrays. An accurate equivalent circuit of high-density TGV arrays is derived based on the results of the proposed cylindrical mode expansion method. Meanwhile, the PMC boundary used in the cylindrical mode method greatly simplifies the corresponding equivalent circuit of TGV arrays. The accuracy and the efficiency of the proposed field-circuit hybrid method are fully validated by comparing it with 2-D quasi-static, 3-D full-wave simulations, and published measurement results. As the method fully captures the scattering and multireflection effects between the vertical cylindrical vias, a very good correlation is obtained between the electrical behaviors obtained by using the proposed method and that by using the 3-D full-wave simulation. [ABSTRACT FROM AUTHOR]

An integrated passive safety system (IPSS), to be achieved by the use of a large water tank placed at high elevation outside the containment, was proposed to achieve various passive functions. These include decay heat removal, safety injection, containment cooling, in-vessel retention through external reactor vessel cooling, and containment filtered venting. The purpose of the passive decay heat removal (PDHR) strategy using the IPSS is to cope with SBO and SBO-combined accidents under the assumption that existing engineered safety features have failed. In this paper, a PDHR strategy was developed based on the design and accident management strategy of Korean representative PWR, the OPR1000. The functions of a steam generator gravity injection and a passive safety injection system in the IPSS with safety depressurization systems were included in the PDHR strategy. Because the inadvertent opening of pressurizer valves and seal water leakage from RCPs could cause a loss of coolant in an SBO, LOCAs during a SBO were simulated to verify the performance of the strategy. The failure of active safety injection in LOCAs could also be covered by this strategy. Although LOCAs have generally been categorized according to their equivalent break diameters, the RCS pressure is used to classify the LOCAs during SBOs. The criteria values for categorization were determined from the proposed systems, which could maintain a reactor in a safe state by removing the decay heat for the SBO coping time of 8 h. The accidents were simulated by MARS code considering several specific processes characterized from LOCA and SBO. For a high-pressure LOCA, water in an IPST could be injected into a steam generator using gravity after depressurization of the secondary circuit caused by opening atmospheric dump valves. For a low-pressure LOCA, the pressure in the RCS naturally decreased due to coolant loss. Additional depressurization was needed during LOCAs for which RCS criteria pressures at the time of estimation were in the range between high-pressure LOCA and low-pressure LOCA. This is referred to as medium-pressure LOCA, according to the range of the RCS pressure. The procedures of the PDHR strategy can be implemented after failure of the steps in emergency operating procedures, before entering the condition for the severe accident management. Even when external conditions make a given site extremely inaccessible, the PDHR strategy can allow for cooling the core in an EDMG by installing an IPSS beside each nuclear power plant. The proposed PDHR strategy can be applied in both current and future nuclear power plants by considering modifications for enhancing their safety. [ABSTRACT FROM AUTHOR]

This paper presents a highly symmetric 1\! :\! n concentric vortical transformer (CVT) technology, which can be implemented with slab inductors. The CVT and several widely used planar transformer structures are analyzed to show the characteristic distinction of the CVT. The proposed CVT was developed in an integrated passive device technology along with the popular distributed active transformer (DAT) for comparison. Under the same real-part impedance transformation ratio at 2.4 GHz, the outer diameter of the CVT is only 48% of the DAT. Moreover, 89.4% transformation efficiency and 191% - \1-dB fractional bandwidth are achieved by the CVT from a high coupling coefficient of 0.9. The symmetric nature of the CVT makes it capable of achieving far less variation than the DAT in resistance and reactance among multiple input ports when used for power combining. [ABSTRACT FROM PUBLISHER]

Presents the table of contents for this issue of the publication. [ABSTRACT FROM PUBLISHER]

ABSTRACT This article presents the design and implementation of a high-performance, compact spiral-coupled directional coupler using an advanced integrated passive device (IPD) fabrication process on a GaAs substrate for use in mobile radio frequency identification (RFID) reader applications. The IPD fabrication step is introduced specifically to enable the directional coupler, which is constructed by the transformation of the intertwined mutual inductors and air-bridges, to have a compact size and high Q-factor. The fabricated coupler achieves only 0.43 dB of insertion loss S21 and it exhibits the coupling S31 of 15.7 dB and the isolation S41 of 27.2 dB. This presented coupler has an extra small size of only 0.72 × 0.82 mm2 and an operational frequency of 910 MHz, which is appropriate for use in an RFID reader system. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2142-2146, 2015 [ABSTRACT FROM AUTHOR]

Purpose – This paper aims to report the investigations of capacitors and inductors embedded into printed circuit boards (PCBs) designed in various layouts. Design/methodology/approach – The research were focused on the components embedded into four-layer PCBs with different structures of the inner layers. Three special capacitive laminates for manufacturing of thin-film embedded capacitors and several types of coils in the form of a spiral, meander and solenoid are described. In addition, a part of the spiral-type coils was formed with an aperture in the center in which the magnetic core, made of soft magnetic composites’ material was placed to increase the coil inductance. Findings – Various constructions of embedded capacitors and coils were designed and manufactured. Capacitance and loss tangent of capacitors to determine the repeatability of the production process were determined. Capacitor’s long-term stability analysis was performed by exposing test samples to elevated temperatures (70, 100 or 130°C), realized with the aid of heating plate, for at least 160 h. The temperature characteristics for the capacitance and loss tangent from 15 to 100°C were determined. Also the induction of different designs and layouts coils was determined. Originality/value – The wide parameters’ characterization of capacitors and coils embedded into PCBs allow the analysis of their properties with regard to their practical application. The promising results of the realized measurements show that the capacitors and induction coils with studied structures can be widely used in the construction of embedded circuits into PCBs (e.g. filters, radio frequency identification systems and generators). [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this study was the use of embedded components technology and innovative concepts of the printed circuit board (PCB) for electronic modules containing field-programmable gate array (FPGA) devices with a large number of pins (e.g. Virtex 6, FF1156/RF1156 package, 1,156 pins). Design/methodology/approach – In the multi-layered boards, embedded passive components that support FPGA device input/output (I/O), such as blocking capacitors and pull-up resistors, were used. These modules can be used in rapid design of electronic devices. In the study, the MC16T FaradFlex material was used for the inner capacitive layer. The Ohmega-Ply RCM 25 Ω/sq material was used to manufacture pull-up resistors for high-frequency pins. The embedded components have been connected to pins of the FPGA component by using plated-through holes for capacitors and blind vias for resistors. Also, a technique for a board-to-board joining, by using castellated terminations, is described. Findings – The fully functional modules for assembly of the FPGA were manufactured. Achieved resistance of embedded micro resistors, as small as the smallest currently used surface-mount device components (01005), was below required tolerance of 10 per cent. Obtained tolerance of capacitors was less than 3 per cent. Use of embedded components allowed to replace the pull-up resistors and blocking capacitors and shortens the signal path from the I/O of the FPGA. Correct connection to the castellated terminations with a very small pitch was also obtained. This allows in further planned studies to create a full signal distribution system from the FPGA without the use of unreliable plug connectors in aviation and space technology. Originality/value – This study developed and manufactured several innovative concepts of signal distribution from printed circuit boards. The signal distribution solutions were integrated with embedded components, which allowed for significant reduction in the signal path. This study allows us to build the target object that is the module for rapid design of the FPGA device. Usage of a pre-designed module would lessen the time needed to develop a FPGA-based device, as a significant part of the necessary work (mainly designing the signal and power fan-out) will already be done during the module development. [ABSTRACT FROM AUTHOR]

A reusable robust radio frequency (RF) biosensor with a rectangular meandered line (RML) resonator on a gallium arsenide substrate by integrated passive device (IPD) technology was designed, fabricated and tested to enable the real-time identification of the glucose level in human serum. The air-bridge structure fabricated by an IPD technology was applied to the RML resonator to improve its sensitivity by increasing the magnitude of the return loss ( S 21 ). The resonance behaviour, based on S 21 characteristics of the biosensor, was analysed at 9.20 GHz with human serum containing different glucose concentration ranging from 148–268 mg dl −1 , 105–225 mg dl −1 and at a deionised ( D ) water glucose concentration in the range of 25– 500 mg dl −1 for seven different samples. A calibration analysis was performed for the human serum from two different subjects and for d -glucose at a response time of 60 s; the reproducibility, the minimum shift in resonance frequency and the long-term stability of the signal were investigated. The feature characteristics based on the resonance concept after the use of serum as an analyte are modelled as an inductor, capacitor and resistor. The findings support the development of resonance-based sensing with an excellent sensitivity of 1.08 MHz per 1 mg dl −1 , a detection limit of 8.01 mg dl −1 , and a limit of quantisation of 24.30 mg dl −1 . [ABSTRACT FROM AUTHOR]

In this paper, fully inkjet printed multilayer capacitors and inductors are fabricated and characterized using poly 4-vinylphenol (PVP) ink as the dielectric layer and silver nanoparticle ink as the conductor. Inkjet printed through vias, created with a novel dissolving method are used to make RF structures in a multilayer inkjet printing process. The vias have been realized in a 350-nm PVP film and exhibit resistance better than 0.1 $\Omega $ . Spiral inductors from 10 to 75 nH have been realized with maximum quality factors around five. The 10-nH inductor exhibits a self-resonant frequency slightly below 1 GHz. Metal–insulator–metal capacitors are realized with densities of 50 pF/mm ^{2} . These capacitors demonstrate values ranging from 16 to 50 pF. The 16-pF capacitor shows a self-resonant frequency over 1.5 GHz. The successful implementation of inductors and capacitors in an all inkjet printed multilayer process with vias is an important step toward fully inkjet-printed large area and flexible RF systems. [ABSTRACT FROM AUTHOR]

This paper presents a simple autonomous chaotic oscillator. The design method is primarily based on a linear oscillator constructed by a closed loop connection of two building blocks, i.e. an inverting active integrator and a passive second-order LC integrator. A diode is inserted in parallel to the two building blocks for inducing chaos. The mathematical model reveals a set of three-dimensional ordinary differential equations, containing seven terms with four constants and an exponential nonlinearity. The dynamics properties are investigated in terms of an equilibrium point, Jacobian matrix, chaotic attractors, bifurcation, Lyapunov exponents, and chaotic waveforms in time domain. The proposed chaotic oscillator potentially exhibits complex dynamical behaviors through the utilization of only six minimal electronic components. [ABSTRACT FROM AUTHOR]

By utilizing lumped coplanar waveguide elements, an on-chip miniaturized triplexer on glass-based integrated passive device (GIPD) process is investigated. Each transmission channel is composed of two parallel LC resonators and an appended L-section network connected in cascade. While the resonators making the path resemble an open circuit at designated frequencies (transmission zeroes), the appended L-section helps create a 50- Ω transmission channel in the third band. In light of this unique approach, the proposed triplexer requires no matching section and features an extremely compact size. According to the experimental results, this on-chip triplexer, while still keeping good in-band/out-of-band performance, is less than one-third the size of the second smallest one in the literature. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a 2.4 GHz SiP radio module with embedded antenna suitable for various operation scenarios like in free space, on metal, and on body, is presented. The size of the whole module is 13.5 × 7.5 × 4.0 mm3. In addition to the antenna, the module includes matching and filter circuits implemented on IPD technology, as well as a radio transceiver. There are no ground plane or no ground plane opening limitations for the underlying electronics board increasing the usability and reliability of the SiP radio module. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2062-2064, 2016 [ABSTRACT FROM AUTHOR]

Ruthroff-type transmission line transformers (TLTs) and baluns prevail over their broadband and low-loss performance. A typical Ruthroff-type balun with a 1:4 step-up impedance transformation ratio was successfully presented using integrated passive devices (IPDs) process. Moreover, two proposed baluns with step-down impedance transformation ratios of 1:1 and 9:4 were developed by modifying the combination of one Ruthroff-type TLT and one Ruthroff-type balun. The two proposed impedance step-down baluns whose balanced impedance is lower than unbalanced impedance make Ruthroff-type balun more flexible for applications; meanwhile, fabricating the baluns using IPD process can help to enhance the low-loss performance. The measured results show that the proposed 1:1 balun exhibits an insertion loss of 0.46 dB with 1-dB fractional bandwidth of 138.9%, and the proposed 9:4 balun exhibits an insertion loss of 0.75 dB with 1-dB fractional bandwidth of 72.4%. The chip areas of the proposed 1:1 and 9:4 baluns, including the pads, are 0.6 and 0.64 mm^2 , respectively. The two proposed baluns are the first on-chip step-down Ruthroff-type baluns and having an option of center tap, which is highly contributive to wideband and high-efficiency power amplifier design. [ABSTRACT FROM PUBLISHER]

Highlights: [•] PSi and TR HR-Si substrates provide HR properties (>3kΩ-cm) for RF applications. [•] The resistivity of trap-rich HR-Si and PSi decrease with temperature increase. [•] Permittivity of PSi is almost 4 times lower than TR HR-Si. [•] The non-linear properties of PSi and TR HR-Si increase with temperature. [•] At high temperature (175°C) PSi behaves better than TR HR-Si. [ABSTRACT FROM AUTHOR]

This paper presents a stacked RF front-end (RFE) package for wideband receiver applications. While having a power consumption of 18 mW, the flipped CMOS chip consisting of a low-noise amplifier and a quadrature down-conversion mixer stacks on a glass integrated passive device (GIPD) substrate, subsequently achieving a noise figure of 2.2–2.8 dB and a conversion gain of 23–25 dB over 1–6 GHz. Moreover, the RFE package uses a GIPD balun with a high common-mode rejection ratio and a post-distortion linearizer in the CMOS mixer, subsequently resulting in an IIP2 of 57–68 dBm and an IIP3 of -5.2–-3.5 dBm over the entire operating band. This paper also elucidates how coupling between the flipped CMOS chip and GIPD balun affects the RFE linearity. Fabricated with 0.18-\mu\ m CMOS technology, the flipped CMOS chip is packaged on the GIPD substrate with a footprint area of \1.8\times \1.8\ \ mm^2. [ABSTRACT FROM PUBLISHER]

This paper presents a novel approach to construct a multiple-input multiple-output (MIMO) antenna in a small package based on integrated passive device (IPD) manufacturing technology. Such an IPD utilizes a thin-film glass substrate that yields a low loss performance for RF components. A thin film process with limited layers available and size considerations in IPD manufacturing pose major challenges in antenna design, especially for multiple antennas. This thin-film process results in a high cavity quality factor (Q) causing a narrowband in the conventional patch antenna. To overcome this problem, this paper develops antenna elements that incorporate a T-shaped coupling fed driven strip and a loop structure. The gap between the driven strip and the loop structure functions as an internal tuning circuit, thus contributing to a lower overall Q and antenna miniaturization. The size of the proposed antenna element is only 1.8\,\times\,0.65 mm^2~(0.031~\lambda0\times 0.011~\lambda0) in the IPD size of 4\,\times\,4 mm^2~(0.068~\lambda0\times 0.068~\lambda0). The experimental results indicate that the antenna achieves a gain of 1.4 dBi and a radiation efficiency of 60% over the IEEE 802.11a band (5.15–5.825 GHz). In addition, the multiple antenna elements are arranged to construct a MIMO system. Furthermore, a good isolation (S21<-15~dB) is achieved using a space of only 0.3 mm (0.005~\lambda) spacing between two antennas, resulting in a compact design and small package (4\,\times\,4\,\times\,0.25 mm^3). The parameters are also investigated in detail, with the experimental results correlating well with the simulation results. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to investigate the thermal behaviour of thin- and thick-film resistor with different dimensions and contacts embedded into printed circuit board (PCB) and compare them to the similar constructions of discrete chip resistors assembled to standard PCBs. Design/methodology/approach -- In investigations the thin- and thick-film embedded resistors with the bar form in different dimensions and configurations of contacts as well as rectangular chip resistors in package 0603 and 0402 were used. In tests were carried out the measurements of dissipated power in temperature of resistor about 40°C, 70°C and 155°C. The power dissipation was calculated as a multiplying of electrical current flowing through the resistor with voltage across the resistor. The dissipation of heat generated by electrical current flowing through resistors was examined by means of the FLIR A320 thermographic camera with lens Closeup × 2 and the power source. Findings -- The results show that, in case of chip resistors, the intensity of heat radiation strongly depends on dimensions of copper contact lands and also depends on the dimensions of the resistor. In case of embedded resistors, with comparable dimensions to chip resistors, they have lower ability to power dissipation, as well as the copper contact lands dimensions have lower influence. The thermal radiation through resin material is not as effective as it is in case of resistors assembled on PCB. However, the embedded thick-film resistors, especially made of paste Minico M2010, have already the similar parameters to 0402 chip resistors. Research limitations/implications -- Research shows that embedded resistors can be used interchangeably with SMD resistors it allows to open up space on the surface of PCB, but it should betaken into account the lower energy dissipation capabilities. It is suggested that further studies are necessary for accurately determining the thermal effects and investigate the structures of embedded passive components that allow for better heat management. Originality/value -- Thermal stability of embedded resistors during operation is a critical factor of success of embedded resistor technology. The way of power dissipation and heat resistance are one of the important operating parameters of these components. The results provide information about the power and the energy dissipation of embedded thin- and thick-film resistors compared to the standard surface mount technology. [ABSTRACT FROM AUTHOR]

Laser-assisted atom probe shows a unique potential in the analysis of embedded Si/metal interfaces, owing to its ability to deliver 3D information with atomic resolution. The interface structures in tri-layer specimens Cu/amorphous Si/Cu are investigated by this technique. For amorphous Si (a-Si) deposited on Cu, a sharp transition occurred with an interface width of 2.4 nm. On the contrary, a much broader mixed zone, 5.3 nm wide, is formed when Cu is deposited on top of a-Si. Only in the latter case, brief annealing leads to immediate nucleation of the Cu3Si. Secondary neutral mass spectrometry confirmed independently the existence of this asymmetry in phase formation and demonstrates linear growth kinetics of the silicide. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

In this paper, three 5-GHz power amplifiers (PAs) are presented, which were implemented in 0.18-\mum CMOS technology on different package substrates using flip-chip assembly. To make a fair comparison, the three PAs use the same circuit topology and transistor peripherals. The first case is a fully on-chip integrated CMOS PA with on-chip inductors. The second case uses low-temperature cofired ceramic (LTCC) inductors for the matching network, and the CMOS die is flip-chip-assembled on the LTCC substrate. For the last case, the CMOS bare die is assembled on the ceramic integrated passive device (CIPD) substrate, also by the flip-chip technique, and CIPD inductors are used as the matching network. Moreover, the PA performances with respect to the quality factor of inductors are discussed and verified with the experimental results. The fully on-chip integrated CMOS PA performs at 25.2 dB gain and 22.5 dBm OPSAT with a peak PAE of 22%. The system-in-package (SiP) CMOS PA on LTCC demonstrates 27 dB gain and 23.5 dBm OPSAT with a peak PAE of 27.5%, and the SiP CMOS PA on CIPD performs with 26.8 dB gain and 24 dBm of OPSAT with a peak PAE of 30%. With low-loss inductors on LTCC or CIPD, the maximum improvements of gain and PAE at PSAT can be up to 1.5 dB and 8 percentage Points, compared to the fully on-chip PA. To our knowledge, this is the first comprehensive PA performance comparison for different SiP approaches. [ABSTRACT FROM PUBLISHER]

Abstract: An integrated passive impedance-loaded SAW H2S sensor working at room temperature has been presented in this paper. The sensor consists of a SAW transponder with delay line structure and a resistive H2S sensor as an impedance-loaded sensor. The SAW delay line was fabricated on a 128° LiNbO3 substrate and its center frequency is 233MHz. The resistive sensor composed of the nano-crystalline SnO2 film and aluminum electrodes was also fabricated on the same substrate. The gas sensing properties of the resistive H2S sensor have been tested separately. In order to maximize the sensitivity of the whole sensor, the resistance of the impedance-loaded sensor was adjusted to match the output impedance of the SAW interdigital transducer (IDT) by changing the resistivity of the Sb-doped SnO2 nano-crystalline films and optimizing the electrode structure. The variation in the return loss magnitude was increased to 2.51dB. Finally, the impedance-loaded SAW sensor was configured and measured wirelessly for various H2S concentrations at room temperature. The measurement results show that the proposed H2S sensor not only has good repeatability and high sensitivity but also is capable of passive wireless detection at room temperature. [Copyright &y& Elsevier]

This paper presents the state-of-the-art technologies currently used to produce high-density integrated capacitors for power systems on-chip applications. The use of high-k dielectrics and 3-D patterning of silicon for reaching high specific capacitance is reviewed. Integrating capacitors monolithically on the active chip or in package of power systems is discussed and solutions are proposed for minimizing series resistance and achieving a high level of integration. A technology based on nanolithography and silicon electrochemical etching is then detailed. It is shown that capacitance densities of up to 700 nF/mm ^2 can be obtained with a submicrometer pores array in a relatively limited thickness. The advantages and disadvantages of further decreasing the pore size to nano-sized pores (below 100 nm) are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] We newly propose the design concept of integrated passive safety system (IPSS). [•] It has five safety functions for decay heat removal and severe accident mitigation. [•] Simulations for IPSS show that core melt does not occur in accidents with SBO. [•] IPSS can achieve the passive in-vessel retention and ex-vessel cooling strategy. [•] The applicability of IPSS is high due to the installation outside the containment. [Copyright &y& Elsevier]

In this paper, miniature branch-line coupler and Butler matrix designs for 2.5-GHz applications are proposed using the glass-based thin-film integrated passive device (TF-IPD) technology. The size reduction is achieved by replacing the quarter-wavelength transmission lines in a conventional branch-line coupler with the bridged-T coil. In this way, the circuit size can be largely reduced without sacrificing the operation bandwidth. The proposed miniature branch-line coupler is then applied to the design of a 4\,\times\,4 Butler matrix centered at 2.5 GHz using the glass-based TF-IPD technology. The measured results show a bandwidth of 2.4–2.6 GHz for better than 13-dB return loss with a maximal dissipation of 4 dB, amplitude imbalance within 1.1 dB, and phase imbalance less than 13^\circ. Notably, the proposed Butler matrix occupies a chip area of 3.13 mm\,\times\,3.3 mm, which is only about 0.026 \lambda 0 \times 0.027 \lambda 0 at 2.5 GHz. [ABSTRACT FROM PUBLISHER]

Purpose – The purpose of this paper is to present the design and manufacture of embedded passive devices in organic substrates. Design/methodology/approach – Low cost and high performance duplexers have been designed for WiMAX front-end modules with multi-layered organic substrates. Band-pass filters (BPFs) and duplexers for the WiMAX FEM have been embedded in organic substrates. In addition, a new organic substrate manufacturing process has been proposed in order to improve the tolerance of embedded passives in organic substrates. Findings – The overall size of FEM, which includes PA and bypass capacitor, is 5.4x4x1.5 mm. BPFs and duplexer show good electrical performances with low insertion loss and high attenuation. The dual-band FEM with embedded passive components incorporates the duplexers including 2 and 5 GHz BPFs. The dimensions of BPFs and duplexer are 1.65x1.8x0.12 mm, 1.32x1.2x0.12 mm and 2x2x0.6 mm, respectively. The integrated dual-band BPFs show an insertion loss < 1.8 dB in path band and 22-40 dB attenuation performance in rejection band. The newly proposed fabrication process improves the tolerance for embedded capacitors in the organic substrate. This new process provides two main advantages. First, the flat coating process is not required. Second, it has a better copper pattern tolerance since the pattern is achieved with the addictive process. The tolerance of capacitances produced by the newly proposed process is compared with one manufactured by the conventional etching process. The newly proposed process provides a better capacitance tolerance. Research limitations/implications – In future studies, it is suggested that the tolerance study should include other variations such as thickness, alignment and material properties. Practical implications – The paper's findings can be used for designing and manufacturing embedded passives devices for wireless applications. Originality/value – This study shows a technology development in the area of embedded passive devices in organic substrates. [ABSTRACT FROM AUTHOR]

An ultra-compact bandpass filter has been developed for 2.3–2.7 GHz worldwide interoperability used for microwave access applications. The proposed filter was fully embedded into a multilayered printed circuit board (PCB) with a high dielectric strontium titanate (SrTiO3) composite film layer. In order to reduce the size of the filter and to avoid unwanted 3-D electromagnetic coupling between the embedded passive filter circuit elements, the proposed filter was designed using J-inverter transformation technology. Two grounding via inductors and a single grounding capacitor were also utilized to generate three independent finite transmission zeros to enhance the rejection characteristics at the proper frequency bands. Since the J-inverter transformed filter circuit elements could be designed with relatively small inductance and large capacitance values, the high dielectric composite film was highly effective in reducing the size and improving the performance of the filter. The high dielectric film exhibited a dielectric constant of 17, a tangent loss of 0.01, and a capacitance density of 12.2 pF/mm^2 at 1 GHz. The measured maximum insertion loss in the passband ranged from 2.3 to 2.7 GHz was better than 1.8 dB, with a minimum value of 1.58 dB at 2.6 GHz. The return loss was higher than 15 dB in the passband. The transmission zeros occurred at 1.71 and 5.1 GHz, and provided suppressions of 45 dB at 1.71 GHz, and 54 dB at 5.1 GHz, respectively. The measured group delay was less than 0.8 ns in the passband. The embedded bandpass filter had a volume of 2.6\,\times\,2.6\,\times\,0.55 (H)mm^3, which is the smallest one found, compared to previously reported devices. the filter, embedded into the eight-layered packaging substrate with the high dielectric composite layer, dramatically reduced the size up to 56%, and its performance was also much improved in comparison to the one embedded into a conventional six-layered PCB. [ABSTRACT FROM AUTHOR]