Rizwan Bashirullah

University of Florida | UF · Department of Electrical and Computer Engineering

The performance of upper-limb prostheses is currently limited by the relatively poor functionality of unintuitive control schemes. This paper proposes to extract, from multichannel electromyographic signals (EMG), motor neuron spike trains and project them into lower dimensional continuous signals, which are used as multichannel proportional inputs...

A completely integrated 3.3 V to 10 Vpk-pk bidirectional switched-capacitor ladder converter is presented for driving the piezo actuators of a 2 mm wing micro-robotic flying insect. The 0.1–10 MHz converter, fabricated in 1.2 V/3.3 V triple-well 0.13 m CMOS, operates as a switched-mode amplifier with 0–3.3 V waveforms at the input and a constant 3x...

This paper presents a 50 nW wirelessly powered implant for the noninvasive monitoring of a bioartificial pancreas postimplantation in nuclear magnetic resonance (NMR) animal studies. The proposed implant increases NMR signal sensitivity across a 190–470 MHz frequency range in both 4.7 and 11.1 T magnetic fields through the use of a wirelessly progr...

A flexible aluminum-silver oxide microbattery activated by a liquid electrolyte for on-demand operation is presented. Four different electrolytes are tested: 1) aqueous sodium hydroxide; 2) blood; 3) urine; and 4) saliva. To start the operation of the microbattery 8 μL of the target electrolyte is pipetted onto the surface of the microbattery. The...

Frequency and time domain models are developed for backplane (BP), printed circuit board (PCB), and silicon interposer (SI) links using six-port transfer matrices (ABCD matrices) for bumps, vias and connectors, and coupled multiconductor transmission lines for traces. The six-port transfer matrix approach enables easy computation of the transfer fu...

This paper summarizes work towards creating mm-scale power converters using high-frequency CMOS as well as MEMS and micro-machined passives. Reducing the converter size is largely motivated by creating power supplies for micro-robotic platforms (with millimeter and milligram scales) without negatively impacting robotic system functionality. MEMS po...

Contemporary electronic systems often contain power circuits to support the unique power conversion or conditioning needs of each of the various subsystems. Each of these power circuits is generally implemented with discrete passive and active electronic components soldered next to the load devices on the printed circuit board. As greater levels of...

This paper presents the design, implementation, and nuclear magnetic resonance (NMR) measurements of a wireless, magnetic compliant, implant that increases the signal sensitivity of NMR images by 3.8dB and 2.6dB in 4.7T and 11.1T magnetic field strengths respectively. The device supports sustained reliable operation through a strongly coupled reson...

This brief presents a majority-voting 1-tap speculative decision-feedback equalization (DFE) architecture wherein the current-mode-logic (CML) selector after the slicers is replaced with a CML majority voter with two instead of three transistors in the stack, thereby resulting in improved speed and increased voltage headroom (or lower supply voltag...

This paper presents a logical effort delay and power model for high-speed current-mode logic (CML) circuits. Current density centric and voltage swing dependent logical effort parameters are defined in terms of the characteristic current density for peak transistor cutoff frequency, which remains relatively constant across different technology node...

In this study, we are pursuing an ultra low-loss interconnect pathway for 3D chip-chip connectivity, incorporating air-clad planar interconnects, air-clad TSVs, and gradual vertical-horizontal transitions. The motivation is to create an air-gap technology that offers the lowest possible effective k-value and near zero loss tangent minimizing the di...

In one embodiment, a neural interface system includes an implantable neural probe having a flexible substrate, electrodes that extend from the substrate that are adapted to contact neural tissue of the brain, a signal processing circuit configured to process neural signals collected with the electrodes, and a wireless transmission circuit configure...

This paper reports a high-frequency DC-DC boost converter capable of sustaining up to 4× the rated process voltage using high-voltage devices fabricated in standard 0.13 μm 1.2 V CMOS without additional masking steps. Integrated Schottky Barrier Diodes (SBD) and high-voltage stacked composite NMOS switches enable processing of large voltages in a 1...

This paper presents a fully-integrated bidirectional SC ladder converter in 0.13μm 1.2V/3.3V triple-well CMOS with peak output voltage of ∼10V. The converter actively drives a 5nF mm-sized piezo-electric robotic wing while following <500Hz arbitrary waveforms at ∼3x step-up conversion. High voltage drive signals for the power switches are developed...

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In this paper we present a compact model for analysis of 3D chip-to-chip interconnect pathways consisting of planar transmission lines, vias, package and pin discontinuities. The model accurately captures signal losses for a wide frequency spectrum with very small error when compared with HSPICE circuit simulations. The interconnect pathway is opti...

In this paper we present the design and fabrication of air-clad planar transmission lines and TSVs that can be used as horizontal and vertical chip-chip interconnects. Performance improvement by using heterogeneous air-clad dielectric is presented for these two types of interconnect structures that establishes the basic motivation for fabricating t...

Presented is a study of the optimal injection frequency using a time-domain model as a technique to improve the noise suppression in injection-locked ring oscillators. It is found that offsetting the injection signal frequency by roughly half of the one-sided lock range relative to the free-running oscillator frequency can lead to higher noise-supp...

In this paper, air cavity transmission lines are integrated into printed circuit boards and packages to enable high-speed low-loss chip-to-chip communication. Microstripline and parallel plate structures with copper conductors separated by an air gap dielectric layer are described. The structures use a sacrificial placeholder material along with co...

The 19 papers in this special cluster focus on wireless power and data telemetry for medical applications. Twelve are focused on implantable systems, while the remaining 7 are primarily concentrated on body-worn/body-centric and close-proximity systems.

This paper reports a digital phase locked loop (D-PLL) based frequency locking technique for high frequency hysteretic controlled dc-dc buck converters. The proposed converter achieves constant operating frequency over a wide output voltage range, eliminating the dependence of switching frequency on duty cycle or voltage conversion range. The D-PLL...

A simple yet accurate delay model based on the method of logical effort is presented for the analysis of high-speed current-mode logic (CML) circuits. The model describes the logical effort of a CML gate in terms of its operating current density normalised to the characteristic current density that yields peak transistor cutoff frequency ( fT ). Si...

This paper reports on experimental measurements performed on a human cadaver and equivalent phantom models to characterize the body as an electrical transmission medium. Since the human body supports current flow through various pathways established by intra-cellular and cellular membranes, an effective communication channel can be established betw...

Analytical models are developed for pulse response of chip-to-chip interconnects modeled as lossy transmission lines. The novel compact physical models capture the losses due to skin effect and dielectric losses and predict both the pulse height and width at the receiver. The work presented in this paper demonstrates the use of these models for opt...

This paper reports on the design, optimization, processing and measurement of an air-cavity transmission line structure on FR-4 boards for high-speed chip-to-chip links. The proposed structure has air as the insulating material, thereby minimizing the dielectric loss. Full-wave electromagnetic simulation is used to predict the performance of the pr...

There are many emerging research efforts exploring bug-sized mobile autonomous robotic systems that roll, crawl, jump, flap or fly. These concepts introduce numerous challenges in mechanical design, ambulation, sensor subsystems, and autonomous navigation/control. Additionally, all micro-robot or micro-UAV operations are ultimately limited by the a...

A selective wirelessly-adjustable multiple-frequency probe (SWAMP) system allows for Nuclear Magnetic Resonance (NMR) imaging and spectroscopy with increased signal sensitivity through the coupling of the NMR surface coil with an implanted system capable of selectively resonating at multiple NMR frequencies. The ability to wirelessly recharge the b...

This paper reports the implementation of high voltage step-up converters in standard 130nm 1.2V CMOS technology. Two hybrid boost converters have been fabricated and are compared, each of which are enabled by the development of enhanced high voltage devices for the standard process: Schottky diodes and stacked NMOS switches. Each device can sustain...

In vivo wireless biomedical microsystems fueled by the continued scaling of electronic components and the development of new micro sensors and micropackaging technologies is rapidly changing the landscape of the electronics and medical industry. These devices can be used for a myriad of monitoring, diagnostic, therapeutic, and interventional applic...

Neural interfaces convert brain signals into outputs that infer brain intentional states. As a communication channel it can be used to implement brain computer interfaces (BCIs) to aid subjects with severe motor disabilities. The realization of this emerging paradigm of neural prosthetics requires extremely low power, small, low noise, highly paral...

We summarize here recent advancements toward integration of electronic passives for electrical power converters. Microscale inductors and capacitors with three-dimensional, free-standing copper traces are formed via a multi-layer molding and electroplating process. This capability creates two complementary routes for passives microfabrication: (a)...

The IEEE Topical Conference on Biomedical Wireless Technologies, Networks, and Sensing Systems (BioWireleSS) will premier in sunny Phoenix, Arizona, at the Renaissance Glendale Hotel 16¿¿¿20 January. This two-day topical conference will be a vital part of the IEEE Radio and Wireless Symposium, featuring the latest developments in wireless biomedica...

The existence of optimal data rates for minimum energy per bit performance in electrical links suggests that dense system connectivity options potentially enabled by D integration and photonics are required for future processing platforms.

Scaling down autonomous robotic systems introduces numerous challenges in mechanical design, electrical/sensor subsystems, and autonomous control. One particularly daunting task is the design of the power system, since this will ultimately limit all microrobot or micro-UAV's operations. Power sources like lithium polymer batteries possess sufficien...

A 100 MHz digitally assisted 4-phase switched-inductor boost converter delivers 240 mW to load voltages of 3 to 5 V with peak efficiency of 64%, and a 45 MHz hybrid switched-inductor/capacitor boost converter delivers 20 mW over a 6 to 10V output range at peak efficiency of 37%. Implemented in a standard 1.2 V 0.13 μm CMOS, the converters use integ...

Perpetual measurement of brain activity in untethered small animal in-vivo experiments requires low power micro-systems incorporating amplification, A/D conversion, and short range wireless transmission. Overall power and communication strategies depend largely on size constraints of the implant site. For extremely small implants, these systems gen...

Introduction It is estimated that over 250 million people worldwide have diabetes, with juvenile diabetes occurring at epidemic levels. Type-I diabetes is a pancreatic disorder in which insulin production is hindered, requiring daily insulin injections, with severe long term health consequences. An alternative therapy is implantable tissue-engineer...

A tissue equivalent phantom (TEQ) was designed and constructed for in vivo biocompatible communication systems operating from 902-928 MHZ (Industrial, Scientific and Medical (ISM) band). The tissue equivalent phantom was designed by first noting the permittivity and conductivity of various tissues in the human torso using the FCC website http://www...

This letter presents progress toward an energy efficient neural data acquisition transponder for brain-computer interfaces. The transponder utilizes a four-channel time-multiplexed analog front-end and an energy efficient short-range backscattering RF link to transmit digitized wireless data. In addition, a low-complexity autonomous and adaptive di...

This paper reports a delay-locked loop (DLL) based hysteretic controller for high-frequency multiphase dc-dc buck converters. The DLL control loop employs the switching frequency of a hysteretic comparator as reference to automatically synchronize the remaining phases and eliminate the need for external synchronization. A dedicated duty cycle contr...

This paper describes a differential current-mode bus architecture based on driver pre-emphasis for on-chip global interconnects that achieves high-data rates while reducing bus power dissipation and improving signal delay latency. The 16-b bus core fabricated in 0.25-mum complementary metal-oxide-semiconductor (CMOS) technology attains an aggregate...

This paper reports a highly integrated neural tag for biosignal streaming data recording. The analog front-end uses a time multiplexed architecture with tunable bandwidth amplifiers, a shared output stage and 8-bit SAR ADC, and achieves an NEF of 2.7 with input referred noise of 18nV/√Hz. Streaming digitized signal recordings are packetized and tra...

This paper presents a feasibility study of a low power electronic RF tagging device and a printed capsule antenna for medication compliance monitoring. RF transponders attached directly to the outer surface of a standard sized capsule can potentially serve as a cost-effective method of validating medication compliance via electronic detection of an...

Chip-to-chip communication across conventional printed circuit boards is limited to low frequencies (a few GHz), thus limiting the aggregate bandwidth without the use of optics. Low-loss, air insulated transmission lines can extend the frequency range of electrical circuitry on fiberglass-epoxy substrates (e.g. FR4 and BT). Described in this paper...

In this paper we present an autonomous and adaptive digital neural signal processor to enable real-time processing of neural signals for brain machine interfaces (BMIs). The algorithms and architectures provide autonomous operation with low computational and hardware complexity. This enables localized processing of neural signals to minimize wirele...

We present the design of an adaptive neural spike detector that dynamically adjusts the spike detection threshold based on the signal to noise ratio of the neural data sets. We propose a self-learning architecture, with a threshold-lock loop that feeds back a spike sorting performance index to the FSM inside the adaptive spike detector. The FSM ref...

A brief focused research effort was performed to examine three critical aspects key to the feasibility of very small single chip CMOS communication nodes called "micronodes." Simulation and analyses were carried out for node operation at 2.4 GHz or 5.2 GHz to determine the practicality of on-chip antennas, adequately stable on-chip frequency refere...

Reports from the Tufts Center for the Study of Drug Development (CSDD) indicate that the average cost to develop a drug in the US is $802 million per drug, of which the clinical trial phase is one of the costliest. During clinical trials, it is important to know with certainty a patient's compliance to a medication regimen, because without it, the...

In the paper we present an RF tagging device that can be attached to the outer surface of a standard sized capsule as a cost-effective method of validating medication compliance via electronic detection of an ingested pill inside the digestive tract. We propose two asymmetric RF tagging architectures that circumvent problems associated with signal...

We report a 4-channel 8 Gb/s/channel transmitter test chip assembled in a low cost 4-layer wirebond BGA package to evaluate the impact of active cross-talk mitigation and equalization techniques on signal performance. A half-rate 4-tap feed-forward and a cross-talk induced jitter equalizer is used to compensate package interconnect losses and data...

• On-chip antenna pair gain at 24GHz is not optimal but sufficient for communication over 5 m near ground. 10-m range is possible if the antennas sit ∼ 50 cm above ground. • It should be possible to communicate to a UAV flying at 50–100m above the ground. • 24-GHz RF circuits with reasonable power consumption should be possible in 130-nm CMOS. It n...

This paper reports a digital phase locked loop (DPLL) frequency locking technique for high frequency hysteretic controlled dc-dc buck converters. The proposed technique achieves constant operating frequency over a wide output voltage range, eliminating the dependence of switching frequency on duty cycle or output voltage conversion range. The DPLL...

This paper presents a 5-Gb/s transceiver for AC-coupled interconnects using de-free signaling based on symbol-rate-carrier offset quadrature phase-shift-keying modulation. A modified Costas loop for the clock and data recovery is also proposed to perform the receiver function. Without the need of an encoding scheme for dc balance, the proposed modu...

Transmitting large amounts of data sensed by multi-electrode array devices is widely considered to be a challenging problem in designing implantable neural recording systems. Spike sorting is an important step to reducing the data bandwidth before wireless data transmission. The feasibility of spike sorting algorithms in scaled CMOS technologies, w...

This paper reports a highly integrated battery operated multi-channel instrumentation system intended for physiological signal recording. The mixed signal IC has been fabricated in standard 0.5microm 5V 3M-2P CMOS process and features 32 instrumentation amplifiers, four 8b SAR ADCs, a wireless power interface with Li-ion battery charger, low power...

Brain-machine interfaces (BMIs) aid disabled humans. BMI systems face challenges such as interfacing with neural tissue, selecting the most appropriate control signals, acquiring data and decoding patient intent in implantable or wearable computers. They must be able to adapt to different variety of behavioral states. Today's hybrid BMI systems con...

This paper presents a feasibility study of printed capsule antennas for medication compliance monitoring. During clinical trials, it is important to know with certainty a patient's compliance to a medication regimen, because without it, the results cannot be interpreted accurately. Small antennas printed directly onto the surface of standard capsul...

This paper reports methods of signal integrity model validation for high-speed I/O chip-package systems including simultaneous switching noise, package power/ground noise and crosstalk. IBIS-models of I/O chip performance are extracted from measurements using high impedance probes. IBIS macro model based SPICE simulations and onboard measurements a...

This brief presents a highly integrated wirelessly powered battery charging circuit for miniature lithium (Li)-ion rechargeable batteries used in medical implant applications. An inductive link and integrated Schottky barrier rectifying diodes are used to extract the DC signal from a power carrier while providing low forward voltage drop for improv...

This paper describes the design and implementation of a high frequency DC-DC converter to directly generate an RF carrier for inductively coupled links in the 6.78 MHz industrial, scientific and medical (ISM) band. The proposed converter topology can also be utilized to dynamically adjust the power supply to improve system efficiency in RF power am...

This paper reports a delay locked loop (DLL) based hysteretic controller for high-frequency multiphase buck DC-DC converters. The DLL control loop employs the switching frequency from a hysteretic comparator to automatically synchronize the remaining phases. A dedicated duty cycle control loop is used to enable current sharing and ripple cancellati...

This paper reviews on-going efforts towards the development of the Florida wireless implantable recording electrodes (FWIRE). The FWIRE microsystem platform is a fully implantable flexible substrate microelectrode array that employs state-of-the-art integrate-and-fire (IF) signal representation and wireless interface circuitry for recording neural...

Near-load DC-DC converter insertion based on multiphase current-sharing topologies and hysteretic control techniques can be used to reduce external current requirements, decrease the size of on-die capacitance and output filter and provide fast load response to enable multiple supply domains in future microprocessor platforms. In this paper, a new...

An electrically small zigzag dipole antenna patterned directly onto the outer surface of a standard sized circular gelatin capsule using screen printed silver colloidal inks is experimentally evaluated for wireless medication compliance applications. The antenna performance inside the human stomach is analysed using the finite difference time domai...

The breadth of challenges that stand between concept generation and realization of the next generation of BMIs calls for tandem and synergistic development of the many facets of neurotechnology. Here, we have provided several examples of how the goal of system development (as opposed to component development) of a fully integrated BMI implant is le...

This paper describes a low power clock and data recovery (CDR) circuit with integrated ASK demodulator for wireless implantable neural recording microsystems. A modulation scheme based on amplitude shift-keying (ASK) and pulse position modulation (PPM) is employed to simplify the complexity of implant circuits and reduce power transmission requirem...

A 16-bit on-chip bus with driver pre-emphasis fabricated in 0.25mum CMOS technology attains an aggregate signaling data rate of 32Gb/s over 5-10mm long lossy interconnects while reducing delay latency by 28.3%, power by 15.0%, and peak current by 70% over a conventional single-ended voltage-mode static bus. The proposed bus is robust against crosst...

A 25-GHz injection locking quadrature LC divider for multi-channel transceivers is described herein. The injection locking technique is used to eliminate the trade-off between quadrature accuracy and phase noise performance. Using harmonic balance to analyze the injection locking behavior, an analytical expression for the locking range is derived....

The effect of process induced variability in long global on-chip interconnects caused by critical dimension control and intrinsic fluctuation of transistor threshold voltage is analysed for current and voltage mode signalling. Projections in scaled CMOS technologies show that current sensing interconnects exhibit smaller mean delay and sensitivity...

This paper describes an adaptive bandwidth bus (ABB) architecture based on hybrid current/voltage mode repeaters for long global RC interconnect static busses that achieves high-data rates while minimizing the static power dissipation associated with current-mode signaling. Attaining a maximum aggregate bandwidth of 16 Gb/s (i.e., 1 Gb/s per line)...

This paper describes an integrated analog front-end for wireless powering and recharging of miniature Li-ion batteries used in implantable neural recording microsystems. DC signal extraction from a wireless carrier is accomplished using Schottky barrier contact diodes with lower forward voltage drop for improved efficiency. The battery charger empl...

An integrated battery management system for low power wireless implantable electronics is presented herein. The system is designed for miniature implantable Li-ion rechargeable batteries with limited cell capacity and employs a new control loop that relaxes comparator resolution requirements, provides simultaneous operation of constant-current and...

A global interconnect scheme with better current return path control is presented for accurate inductance analysis and robust interconnect design. High performance is obtained by using differential signaling, current-mode sensing, bridge termination, and driver pre-emphasis.

By using current-sensing differential buses with driver pre-emphasis techniques, power dissipation is reduced by 26.0%-51.2% and peak current is reduced by 63.8%, compared to conventional repeater insertion techniques, for 10mm long buses in TSMC 0.25μm technology. This proposed architecture lowers the worst coupling capacitance to total capacitanc...

A novel masking technique that enables the complex patterning of metal on any layer of a released MEMS chip is demonstrated. This technique enables a polysilicon only MEMS process to create low-loss RF devices. To illustrate the advantages of post-release metallization, in a polysilicon only MEMS process, a rotating MEMS tunable capacitor that prov...

This paper presents a design methodology of a highly efficient power link based on Class-E driven, inductively coupled coil pair. An optimal power link design for retinal prosthesis and/or other implants must take into consideration the allowable safety limits of magnetic fields, which in turn govern the inductances of the primary and secondary coi...

This brief describes an adaptive bandwidth bus architecture based on hybrid current/voltage mode repeaters for long global RC interconnect static busses that achieves high-data rates while minimizing the static power dissipation associated with current-mode (CM) signaling. An experimental adaptive bandwidth bus test chip fabricated in AMI 1.6-/spl...

An adaptive bandwidth bus (ABB) uses both current and voltage sensing techniques to improve interconnection delay and signaling bandwidth compared to conventional static busses. Attaining a maximum aggregate bandwidth of 16Gb/s (i.e. 1Gb/s per line) across lossy on-chip interconnects spanning 1.75cm in length, the bus core fabricated in TSMC 0.35 μ...

This paper presents the design of a highly efficient power link based on class-E driven, inductively coupled coil pair. An optimal power link design for retinal prosthesis and other implants must take into consideration the allowable electric and magnetic field safety limits, which in turn govern the inductances of the primary and secondary coils....

This paper describes a closed-loop wireless inductive power transfer system for an implantable retinal prosthetic device. The proposed system is designed to ensure optimal power transfer to the implanted unit despite coil displacements and changes in load current while minimizing the sensitivity to component and process variation. Based on the syst...

Based on the effective attenuation constant approximation of distributed RLC lines, simplified design guidelines are presented dealing with the line characteristics, termination, and delay estimation of on-chip global interconnects. RC delay models are verified to be still accurate for a wide range of parameters conventionally considered inductive....

Retinitis pigmentosa (RP) and age-related macular degeneration (AMD) are incurable diseases that result in profound vision loss due to degeneration of the light sensing photoreceptors. However, the discovery that direct electrical stimulation of the retinal neurons creates visual sensation has inspired prosthetic devices aimed to restore useful vis...

This paper addresses propagation delay and power dissipation for current mode signaling in deep submicrometer global interconnects. Based on the effective lumped element resistance and capacitance approximation of distributed RC lines, simple yet accurate closed-form expressions of delay and power dissipation are presented. A new closed-form soluti...

This paper describes a smart bi-directional telemetry unit for an implantable retinal prosthetic device. The system is designed to deliver 250 mW to the intra-ocular unit via an inductive link and provide wireless communication capability. A novel dual frequency carrier approach is used to optimize the power link for maximum transfer efficiency and...

A simple yet accurate closed-form delay expression for inverter driven on-chip interconnects with arbitrary receive-end termination is presented. The solution can be used for both resistive and capacitive termination to adequately model current and voltage mode sensing schemes. The model is extended to consider fast input slope and input-to-output...

In this paper, a Ka-band power amplifier based on a resonant slotted-waveguide-to-microstrip power-dividing/combining circuit is presented. The advantages of this structure are its low profile, ease of fabrication, as well as its potential for high power-combining efficiency. In addition, efficient heat sinking of monolithic microwave integrated ci...

This paper describes a low-power design methodology for a bus architecture based on hybrid current/voltage mode signaling for deep sub-micrometer on-chip interconnects that achieves high data transmission rates while minimizing the number of repeaters by nearly 1/3. The technique uses low-impedance current-mode sensing to increase the data throughp...

A new technique for reducing noise crosstalk due to inductive effects in high-speed switching environments is presented. A signalling scheme based on raised cosine approximation (RCA) pulses is used to achieve gradual buffer turn on without any speed penalties. A new current-mode RCA line driver is proposed and incorporated in a 16 bit 1 Gbit/s off...

In this paper, closed-form expressions of delay and power dissipation based on the effective lumped element resistance and capacitance approximation of distributed RC lines are presented. A new closed-form solution of delay under step input excitation is developed, exhibiting an accuracy that is within 5% for a wide range of parameters. The usefuln...

The field of integrating a dysfunctional biological subsystem with microelectronic systems is an emerging and fast growing one. The main functionality of the implantable microelectronics are (1) biochemical sensor for sensing of vital life signs, oxygen, pH, glucose, temperature, and toxins by miniaturized chemical and bio-sensors; (2) telemetry, t...

With the recent surge in popularity of RF and Microwave MEMS many different device topologies are being explored. Some devices provide large changes in capacitance, but lack the ability to provide a linear range of capacitance values between the minimum and maximum values of the device. We present a device design for a low-loss rotating MEMS tunabl...

Presented herein is a fully integrated low-noise CMOS multi-channel amplifier for neural recording applications. The circuit employs the chopper modulation technique to reduce the effect of flicker noise and DC offset. A reduced area design implementation is achieved by trading off the increased noise margin performance of the chopper modulator for...

Presents a new signaling scheme designed for today's aggressive process interconnect scaling aimed at reducing cross-talk noise. The scheme uses band-limited basis waveforms or raised cosine approximation (RCA) pulses to minimize the crosstalk noise due to higher frequency components. Simplified interconnect modeling shows that this technique is pa...

A power-amplifier array based on a slotted-waveguide power divider is presented for quasi-optical applications. The advantages of this structure are its low profile and ease of fabrication. Furthermore, efficient heat sinking of power devices is achieved. An X-band version of the power amplifier using eight MESFET's was designed and fabricated. An...