E. Cantatore

Eindhoven University of Technology | TUE · Department of Electrical Engineering

Powering the increasing number of sensor nodes used in the Internet of Things creates a technological challenge. The economic and sustainability issues of battery-powered devices mean that wirelessly powered operation—combined with environmentally friendly circuit technologies—will be needed. Large-area electronics—which can be based on organic sem...

This brief presents four small-area SAR ADCs with a resolution from 8 to 11 bits. Two area-saving techniques are utilized. First, the DAC layout is implemented with custom designed unit-length capacitors, which are optimized for each resolution to minimize the chip area. Second, dynamic logic is applied to the 8-bit design to further reduce the num...

This brief presents a 10.5-bit 10 MS/s successive-approximation-register (SAR) analog-to-digital converter (ADC) with $1.5\times $ input range (IR). By pre-setting and resetting the most significant bit (MSB) of the digital-to-analog converter (DAC) to shift the input signal accordingly, the input range of the ADC is enhanced by a factor of 1.5....

This article presents a second-order noise-shaping successive-approximation-register (SAR) analog-to-digital converter (ADC) that employs a duty-cycled amplifier and digital-predicted mismatch error shaping (MES). The loop filter is composed of an active amplifier and two cascaded passive integrators to provide a theoretical 30-dB in-band noise att...

This brief presents the analysis, design, and measurements of a compact analog frontend for a catheter-integrated ultrasound imaging digitizer. This frontend requires several functions, including single-ended-to-differential conversion, AC coupling, amplification, anti-aliasing, and the capability to drive the subsequent ADC. To minimize chip area...

Large-area, flexible proximity-sensing surfaces are useful in a range of applications including process control, work security and robotics. However, current systems typically require rigid and thick electronics, which limit how they can be used. Here we report a flexible large-area proximity-sensing surface fabricated using printed organic materia...

This work presents a prototype system based on a multichannel receiving (RX) integrated circuit (IC) for contrast-enhanced ultrasound (CEUS) imaging. The RX IC is implemented in a 40-nm low-voltage CMOS technology and is designed to interface to a capacitive micromachined ultrasonic transducer array. To enable a direct connection of the RX electron...

IoT sensor nodes have requirements that are profoundly different from more traditional electronic applications. They often rely on miniature batteries for power supply, but demand limited accuracy. For this reason, radically new sensor interfaces architectures have been conceived, which ensure record-low average power and energy per measurement, wh...

This paper presents a multiplexed current sensitive readout for label-free zeptomolar-sensitive detectors realized with large area Electrolyte Gated Organic Thin Film Transistors (EGOFETs). These highly capacitive biosensors are multiplexed using an OTFT line driver and OTFT switches, and interfaced to a 65-nm Si CMOS, low power, pA-sensitive front...

This article presents a first-order continuous-time (CT) noise-shaping successive-approximation-register (NS-SAR) analog-to-digital converter (ADC). Different from other NS-SAR ADCs in literature, which are discrete-time (DT), this ADC utilizes a CT Gm-C integrator to realize an inherent anti-aliasing function. To cope with the timing conflict betw...

This paper presents a front-end integrated circuit for ultrasound (US) harmonic imaging, interfacing to a one-dimensional capacitive micromachined ultrasonic transducer (CMUT). It contains a complete ultrasound receiving chain, from analog front-end (AFE) to gigabit/s data link. A two-stage self-biased inverter-based transimpedance amplifier (TIA)...

An ultra-low power, energy efficient, and versatile resistive sensor interface for energy constrained internet-of-things applications is presented. The sensor interface includes an efficiently duty-cycled current digital-to-analog converter (I-DAC) and an asynchronous successive approximation register (SAR) analog-to-digital converter (ADC), which...

Organic printed electronics is an attractive platform to develop mechanically flexible and cost-effective solutions for innovative applications such as foldable displays, flexible sensing surfaces, or biomedical instrumentation that can adapt to the shape of the body. Despite the growing interest and the recent advancements of printed electronic te...

This paper presents an ultrasound rangefinder system able to find relative distances among energy-constrained sensor nodes. The nodes build a swarm that is operated in collision and multipath rich environments. A new distance measurement technique combining Wake-up and Frequency Modulated Continuous Wave (FMCW) is proposed to enable the ranging whi...

This chapter provides a detailed overview of amplifier topologies that can be manufactured using organic thin-film transistors (OTFTs). Advantages and drawbacks of unipolar and complementary OTFT technologies are discussed. In the rest of the chapter, unipolar and complementary amplifier solutions are presented in sequence. First elementary unipola...

Advancements in the field of flexible electronics have enabled many novel applications such as wearables, flexible large-area displays, and textile-based sensor systems. A widely used semiconductor material for flexible electronics is amorphous indium gallium zinc oxide (a-IGZO). When compared to other semiconductors suitable for flexible technolog...

This work presents a 14-bit oversampled successive-approximation-register (SAR) analog-to-digital converter (ADC) with mismatch error shaping (MES) and pre-comparison techniques. A pre-comparison technique is proposed to solve the over-range problem caused by MES. With MES and pre-comparison, the digital-to-analog converter (DAC) mismatch error can...

With the advent of the internet of things, flexible wearable devices are gaining significant research interest, as they are unobtrusive, comfortable to wear and can support continuous observation of physiological signals, helping to monitor wellness or diagnose diseases. Amorphous Indium Gallium Zinc Oxide (a-IGZO) Thin Film Transistors (TFTs) fabr...

This brief provides an overview of recent advancements in printed flexible electronics, focusing on both circuit design and emerging applications of organic thin film transistors, including radio-frequency identification, organic sensors and their electronic interfaces. Printed circuits are low cost and large area, and thus enable applications wher...

This paper presents the design and experimental characterization of an ultrasound rangefinder system. A new distance measurement method is proposed for determining the relative position among sensor nodes that are operated in a collision and multipath rich environment, while needing no common time reference between them. A 65nm CMOS technology has...

This work presents a simplex and a full-duplex digital communication interface in 65 nm CMOS that enhance the energy efficiency of chip-to-chip digital communication in low-speed low-power systems, e.g., for Internet-of-Things applications. A capacitive fully dynamic simplex interface is proposed first. A self-interference cancellation network is t...

This letter describes a miniature, ultra low power, all-dynamic temperature sensor based on a duty-cycled resistive transducer bridge and a 9-bit asynchronous SAR ADC in 65-nm CMOS. It features a novel floating bridge technique and automatic power gating to achieve the lowest reported power consumption. It consumes 2.18 pJ per conversion and has an...

An ultra-low-power fully dynamic capacitance-to-digital converter (CDC) that exploits a novel charge reuse technique is proposed. The CDC includes a capacitive bridge as the sensing frontend and an asynchronous successive approximation register ADC for signal digitization. Passive charge sharing between the frontend and ADC is used to enable a full...

This paper presents the design and experimental characterization of an ultrasound transceiver. The transceiverincludes an on-chip transmitter and a receiver to be used in asymmetric data-link, where each sensor node has limited energy resources and is operated in air or a fluidic environment. The receiver and the transmitter operate from a 0.8V sup...

In this work is presented a gravure-printed unipolar Organic Thin-Film Transistor (OTFT) technology able to achieve state-of-the-art yield performance. A multilayer cross-linked dielectric is printed to reduce gate-leakage defects, which have been found to be one of the main failure mechanisms in previous printed OTFTs. The defectivity analysis per...

A versatile, low-power, and energy-efficient capacitance-to-digital converter (CDC) for Internet-of-Things (IoT) is presented, based on an all-dynamic architecture with adaptable speed, resolution, and range. The proposed CDC includes a single-armed capacitive bridge and a differential switched-capacitor 10-b asynchronous successive approximation r...

A biopotential front-end (FE) circuit is designed and fabricated using amorphous indium-gallium-zinc-oxide (a-IGZO) TFTs on flexible plastic substrate. Its input chopper provides both noise reduction and frequency division multiplexing among multiple FEs in an array. Measurements of the FE at chopping frequencies from 5 to 8 kHz show a gain in the...

A versatile, low power and energy efficient Capacitance-to-Digital Converter (CDC) for Internet-of-Things (IoT) is presented, based on an all-dynamic architecture with adaptable speed, resolution and range. Sampling rates from 1S/s up to 100kS/s are supported and capacitances from 1.23 to 24.59pF can be digitized while the power scales inherently f...

This paper presents an ultrasound (US) transceiver including a transmitter and a receiver for underwater wireless sensor nodes, where low-power operation is desired to extend the lifetime of the network. A system-level analysis of the underwater communication has been performed by taking into account the underwater propagation and the medium charac...

This work introduces a novel adaptation framework to energy-efficiently adapt small-sized circuits operating under scarce resources in dynamic environments, as autonomous swarm of sensory agents. This framework makes it possible to optimally configure the circuit based on three key mechanisms: (a) an off-line optimization phase relying on R2 indica...

This paper presents a 7.7‐mm² on‐chip LED driver based on a DC/DC resonant hybrid‐switched capacitor converter operating in the MHz range with and without output capacitor. The converter operation allows continuously dimming the LED while keeping control on both peak and average current. Also, it features no flickering even in the absence of output...

Recent years have witnessed significant research efforts in flexible organic and amorphous-metal-oxide analogue electronics, in view of its formidable potential for applications such as smart-sensor systems. This book provides a comprehensive overview of this growing research area. After discussing the properties of organic and amorphous-metal-oxid...

This paper presents an integrated light-emitting diode (LED) driver based on a self-resonant hybrid-switched-capacitor converter (H-SCC) operating in the megahertz range. An integrated zero-current detection (ZCD) circuit is designed to enable self-resonant operation and zero-current switching. A self-resonant timer is proposed to set the switching...

A versatile resistive temperature sensor for Internet-of-Things (IoT) is presented, based on an all-dynamic architecture. This allows efficient scaling of power with conversion rate, enables optional oversampling for an adaptable resolution, and provides efficient adaptability to different resistor values. A new double-sided measurement mode is pro...

Various aspects in device engineering were tackled to realize a high-performance, low-voltage operating organic field effect transistor on plastic substrate. Contact resistance between the active layer and metal electrodes was decreased by employing oxide interfacial layers. The anodization of the Al gate served as a high capacitance dielectric lay...

This paper presents a LED driver IC based on a self-resonant Hybrid-Switched Capacitor Converter (H-SCC) operating in the MHz range. Capacitors and switches of the LED driver are integrated on-chip in a low-cost 5V 0.18μm bulk CMOS technology. The effective chip area is 7.5mm². A conventional SMD output capacitor and a 6.4 mm² 150nH SMD air-core in...

The papers in this special section were presented at the 46th European Solid-State Circuits Conference (ESSCIRC) that was held in Lausanne, Switzerland, September 13–15, 2016.

In this paper, we propose a unified physical model of InGaZnO [amorphous indium-gallium-zinc-oxide (a-IGZO)] thin-film transistors (TFTs) accounting for both charge injection at the contact and charge transport within the channel. We extract the current-voltage characteristics of the injecting contact from the measurements of a-IGZO TFTs fabricated...

This paper presents a noise-reconfigurable resistive feedback amplifier with current-reuse technique for fetal ECG monitoring. The proposed amplifier allows for both tuning of the noise level and changing the power consumption according to the signal properties, minimizing the total power consumption while satisfying all application requirements. T...

Three novel differential amplifier topologies using double gate a-IGZO TFTs on flexible substrate are presented in this paper. The designs exploit positive feedback and a load with self-biased top gate to achieve the highest static gain in single stage a-IGZO amplifiers reported to date. After fabrication, the three amplifiers exhibit respectively...

Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field...

Supplementary Figures 1-7 and Supplementary References

Here we show a new physical-based analytical model of a-IGZO TFTs. TFTs scaling from L=200 μm to L=15 μm and fabricated on plastic foil are accurately reproduced with a unique set of parameters. The model is used to design a zero-VGS inverter. It is a valuable tool for circuit design and technology characterization.

Applications addressed by large-area electronics give the motivation to push further the research on large-area TFT manufacturing processes and circuit design. Since the birth of electronics, the main research goals have been miniaturization and increasing computational power. Today’s focus is turning back to people, and electronics aims now to per...

Any reliable circuit designs is based on compact models able to describe accurately the behavior of the TFTs in a given technology. With our modeling, accurate simulation of analog circuits in a CAD platform is enabled and deeper insight in the underlying transport mechanisms is achieved. Thus, a physical model was developed in house that guarantee...

After the physical signal is converted to the electric domain, filtered and amplified, it must be quantized and converted into a digital word. The analog to digital conversion can be performed following many different approaches; the chosen one should take into account various aspects, like application specifications and signal properties. In our c...

The first integrated circuits date back to the 1950s. From that moment, humanity witnessed an impressive growth of electronics presence in everyday life. This growth is not going to stop, and will also involve innovative applications that, contrary to most product nowadays, will not be based on high computational power or ultra-fast mobile data com...

The technologies that have been developed to address large-area and low-cost applications have been developed very recently and still pose severe limitations to the complexity achievable by integrated circuits. The transistor performance is limited and the process variations still represent a concrete issue with respect to circuit yield. In this ch...

Digital circuits are extensively used in any integrated system, sometimes to assist analog or mixed-signal functions and sometimes to perform logical operations. In both cases, logic gates should achieve high gain and large noise margin in order to provide robustness and enable high circuit yield. In this chapter, a new logic style is proposed that...

Ambipolar transistors typically suffer from large off-current inherently due to the ambipolar conduction. Using a tri-gate transistor we show that it is possible to electrostatically switch ambipolar polymer transistors from ambipolar to unipolar mode. In unipolar mode symmetric characteristics with an on/off current ratio of larger than 10 (5) are...

Miniature [Formula: see text]-sized sensor nodes have a very tight power budget, in particular, when a long operational lifetime is required, which is the case, e.g., for implantable devices or unobtrusive IoT nodes. This paper presents a fully integrated signal acquisition IC for these emerging applications. It integrates an amplifier with 32 dB g...

The continuous advancements in printed electronics make nowadays feasible the design of printed circuits which enable meaningful applications. Examples include ultra-low cost sensors embedded in food packaging, large-area sensing surfaces and biomedical assays. This paper offers an overview of state-of-the-art digital and analog circuit blocks, man...

This paper presents a three-channel frontend system for fetal monitoring applications which includes three amplification chains, an ADC and all power management circuitry needed to feed the different building blocks from a single 1.4V supply. The specifications of the proposed system (0.38μVrms equivalent input noise, 74.5dB dynamic range and 0.5 t...

A unified drain current model of complementary (p- and n-type) organic thin film transistors (OTFTs) is presented. The model is physically based and takes into account the detailed properties of the organic semiconductor through the density of states (DOS). The drain current depends on the geometrical and physical parameters of the transistor, on t...