This work presents a sub-μW on-chip oscillator for fully integrated system-on-chip designs. The proposed introduces resistive frequency locked loop topology accurate clock generation. In this topology, switched-capacitor circuit is controlled by an internal voltage-controlled (VCO), and the equivalent resistance of matched to temperature-compensated resistor using ultra-low power amplifier. design yields from VCO. approach eliminates traditional comparator oscillation loop; typically...

We present a discontinuous harvesting approach for switch capacitor dc-dc converters that enables ultralow-power energy harvesting. Smart sensor applications rely on harvesters to scavenge across wide range of ambient power levels and charge the battery. Based key observation source efficiency is higher than pump efficiency, we technique decouples two efficiencies better tradeoff. By slowly accumulating an input then transferring it battery in burst mode, converter switching leakage losses...

This paper presents an energy-autonomous wireless communication system for ultra-small Internet-of-Things (IoT) platforms. In the proposed system, all necessary components, including battery, energy-harvesting solar cells, and RF antenna, are fully integrated within a millimeter-scale form factor. Designing energy-optimized such miniaturized platform is challenging because of unique constraints imposed by dimension. The targets orders magnitude improvement in energy efficiency through...

Enabling long range (>10m) wireless communication in non-line-of sight (NLOS) scenarios would dramatically expand the application space and usability of mm-scale sensor nodes. The major technical challenges posed by a form-factor are poor antenna efficiency small instantaneous current limit (~10s μA) thin-film batteries. We address these several ways: 1) found that magnetic dipole achieves better at an electrically-small size than electric dipole, when antennas resonated with off-chip lumped...

We present a millimeter-scale near-field radio system for ultra-low-power (ULP) healthcare sensor nodes. It is specifically designed `syringe implantation' which minimizes invasiveness of implantation. Designing wireless node implanted challenging because: 1) the antenna constrained to diameter syringe needle, significantly constrains link distance through RF. 2) The energy/power are strictly limited by form-factor where thin-film batteries can source only <;10μAh and sustain <;50μA peak...

Small form-factor piezoresistive MEMS sensors, often configured in a Wheatstone bridge, are widely used to measure physical signals such as pressure [1-3], temperature [4], force [1], and gas concentration. A common method realize digital output from the bridge involves biasing with DC voltage source using low-noise amplifier followed by an ADC. While measurement can achieve high resolution linearity, it is very power hungry [3] because resistance low (typically 1–10kΩ). Both instantaneous...

We present a near-field radio system for millimeter-scale wireless smart sensor node that is implantable through 14-gauge syringe needle. The proposed integrates on chip and magnetic antenna glass substrate within total dimension of 1 × 10 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . demonstrate energy-efficient active communication between the base station device an RF energy-absorbing tissue. transceiver, digital baseband...

Two prototypes of low-power back-channel (BC) Bluetooth low-energy (BLE) wake-up receivers are presented. The scan the BLE advertising channels for modulated channel patterns by hopping local oscillator (LO) frequency. BC message is in sequence three each event. This makes via messaging compatible with standard, so it can be generated a commercial offthe-shelf device. first proposed receiver uses dual mixer to downconvert RF input reduce ring-based LO power consumption operating at half...

Wireless communication has been a limiting factor for achieving millimeter-sized wireless sensor nodes because of the high power consumption, large antenna size and off-chip components typically required. Several mm-scale radios have proposed [1-3]; however, all use proprietary protocols, which afford their designers more flexibility to address above challenges. For interoperability ubiquitous adoption, it is important that standard such as Bluetooth Low Energy (BLE). However, implementing...

This paper presents a low power, fully-integrated Bluetooth Low-Energy (BLE) transmitter (TX) for Internet-of-Things (IoT) applications. The complete BLE TX achieves total energy per bit of 3.5nJ in an open-loop transmission scheme due to the ultra-low startup system. overall system architecture includes RF front-end, 16 MHz crystal oscillator (XO), GFSK modulator, and digital baseband including SPI interface. An enhanced capacitively loaded three-stage inverter chain XO is proposed,...

Wireless transceivers traditionally perform local-oscillator (LO) calibration using an external crystal oscillator (XTAL) that adds significant size and cost to a system. Removing the XTAL enables true single-chip radio, but alternate means for calibrating LO is required. Integrated references like on-chip LC [1] or relaxation [2] oscillators are either high power have PVT sensitivity too wireless standards. Multiple crystal-less radios address this challenge [3]-[6]. [3] replaces with FBAR...

In this article, we present a crystal-less Bluetooth low-energy (BLE) transmitter using RF reference recovery directly from GFSK-modulated BLE packets. order to achieve fast frequency calibration modulated signals and reduce interference other users, the transceiver consists of back-channel wake-up receiver, clock-recovery transmitter, dual-all-digital phase-locked loop (ADPLL) synthesizer for system wake-up, clock-recovery, packet transmission, calibration. An embedded averaging processing...

Abstract Nodes in original S-MAC protocol just can visit the channel scheduling and listening stage. The working schema may result data latency high conflict. To solve those above problems, we split duty into multiple micro-duties. By using different micro-dispersed contention channel, sensor nodes reduce collision probability of data. Aiming at detecting fixed cycle protocol, on basis micro-duty buffer queue length, this paper presents an adaptive back-off algorithm. While algorithm with...

Recent advances in circuits have enabled significant reduction the size of wireless systems such as implantable biomedical devices. As a consequence, battery integrated these has also shrunk, resulting high internal resistances (~10kΩ). However, peak-current requirement power-hungry components radios remains mW range, and hence cannot be directly supplied from battery. Therefore, duty-cycled architectures pulsed-based been proposed that transmit short burst (~1μs) power (~10mW) by an energy...

The internet of things has enabled the communication "smart" physical objects and improved quality machine service to humans. These achievements are based on synergy processing information collected by different sources. This trend will continue with next class computing platforms millimeter-scale sensors, diversifying signal sources including biomedical, climate surveillance targets. key challenge such systems is achieve small die size, ultra-low power consumption, sufficient distance...

We present a discontinuous harvesting approach for switch capacitor DC-DC converters that enables ultra-low power energy harvesting. By slowly accumulating charge on an input and then transferring it to battery in burst-mode, switching leakage losses the converter can be optimally traded-off with loss due non-ideal MPPT operation. The harvester uses 15pW mode controller, automatic conversion ratio modulator, moving sum pump low startup upon switch. In 180nm CMOS, achieves >40% end-to-end...

This paper presents a new impulse based ultra-wide band (UWB) transceiver system designed in 90nm CMOS technology for UWB medical radar sensing and communication applications. The design is targeting human heart motion detection short range data communications. transmitter composed of simple on-off keying (OOK) modulated generator variable gain-controlled amplifier (VGA) at the transmitter. generated pulse width can be adjusted. receiver operating mode low noise amplifier, mixer, an...

In recent years wireless body area sensor networks (WBASN) has gained a lot of attention from researchers for its promising application in medical care and health field. However, previous studies are typically involved the deployment performance WBASN, most research barely considered details hardware software platforms. Furthermore, few existing platforms can meet need practical their larger physical size, higher power consumption, etc. this paper, hardware-software platform (HSPF) is...

The development of Micro-ElectroMechanical Systems ,integrated circuits, wireless communications have resulted in the creation miniature, ultra-low power, and wearable health monitoring system. system can be defined as a Body Sensor Network that embedded user’s outfit part clothing .This 3ACare is alert which give anyone care at anytime anywhere. continuously collects multiple vital signs by physiological sensors evaluates personal server such PDA. And transfers data to medical center 3G net...

This paper presents a 1.3 μW backscatter-based transceiver for battery-powered millimeter-scale sensor nodes. By taking advantage of the coherence reflected dual-side bands, it attains an optimum SNR and improved interference rejection with low-power, non-coherent binary modulation. Integrated 2.1×4 mm planar antenna in complete, crystal-less node, achieves 3.5 m communication distance reader transmitting 31 dBm equivalent isotropic radiated power (EIRP).

Introduction Previous study has identified increased antithrombin III (ATIII) in patients with major depressive disorder (MDD), supporting ATIII as a potential biomarker for depression diagnosis. Objectives This aimed to reveal the alteration of after occipital repetitive transcranial magnetic stimulation (rTMS), and illuminate its power evaluate predict curative effects MDD treatment. Methods A total 90 were recruited further intervened rTMS individualized, standard or sham treatment five...

This topic takes the miniature Pt resistance strain pressure sensor made by Institute of Electronics, Chinese Academy Sciences, as core sensing element, and designs corresponding high-precision, low cost, power amplifying circuit so to realize accurate detection atmospheric in time. In this topic, a new design is taken, which first connects digital potentiometer bridge adjust its balance, then amplifies output signal once ideal value. not only meets requirement measurement, but also feasible...

We present a fully integrated energy reservoir unit using counter flow method for peak power delivery in space-constrained sensor systems. Recent advances circuits have enabled significant reduction the size of wireless systems such as implantable biomedical devices. As consequence, batteries these also shrunk, resulting high internal resistances (~10 kQ). However, current requirement power-hungry components radios remains milliwatt range and hence cannot directly be supplied from battery....