Digitally Intensive Frequency Synthesis and Modulation Exploiting a Time-mode Arithmetic Unit

Reducing power consumption is becoming increasingly important for the sustainability of the communication industry because it is expected to consume a significant portion of the global electricity in the face of the exponentially increasing demands on the volume and rate of data transmission. As the scope narrows to the individual wireless...

A Low-Spur Fractional-N PLL Based on a Time-Mode Arithmetic Unit

This article introduces a low-jitter low-spur fractional-N phase-locked loop (PLL) adopting a new concept of a time-mode arithmetic unit (TAU) for phase error extraction. The TAU is a time-signal processor that calculates the weighted sum of input time offsets. It processes two inputs - the period of a digitally controlled oscillator (DCO)...

Energy-efficient seizure detection for wearable EEG

With the development of machine learning techniques, more and more classification models have been designed for seizure detection. The creation of these models has dramatically improved the convenience of epilepsy detection and made seizure labeling automation possible. However, many of the current researches in this field use EEG datasets with...

Ultra-Low Energy Time-Mode ADC with Background Calibration for Biomedical Sensing Applications

Biomedical engineering focuses in advancing health care by taking advantage of the technological improvement. An important part of biomedical engineering is biomedical sensing, that focuses in the acquisition of biopotential signals. Through time, a lot of research has been done on the acquisition of biopotential signals and a variety of methods...

Monolithic integration of a smart temperature sensor on a modular silicon-based organ-on-a-chip device

One of the many applications of organ-on-a-chip (OOC) technology is the study of biological processes in human induced pluripotent stem cells (iPSCs) during pharmacological drug screening. It is of paramount importance to construct OOCs equipped with highly compact in situ sensors that can accurately monitor, in real time, the extracellular...

A 10-bit, 771 nW Time-Mode ADC with a 2-Step TDC for Bio-Signal Acquisition

In this paper, we present the design of a low-voltage, low-power, and small-area time-mode ADC (TM-ADC) for bio-signal sensing applications. The proposed time-mode ADC (TM-ADC) consists of a programmable oversampling ratio (OSR), voltage-controlled ring oscillator (VCRO) based analog-to-time converter (ATC), followed by an asynchronous unfolded...

A Chip Integrity Monitor for Evaluating Moisture/Ion Ingress in mm-Sized Single-Chip Implants

For mm-sized implants incorporating silicon integrated circuits, ensuring lifetime operation of the chip within the corrosive environment of the body still remains a critical challenge. For the chip's packaging, various polymeric and thin ceramic coatings have been reported, demonstrating high biocompatibility and barrier properties. Yet, for...

An energy efficient time-mode digit classification neural network implementation

This paper presents the design of an ultra-low energy neural network that uses time-mode signal processing). Handwritten digit classification using a single-layer artificial neural network (ANN) with a Softmin-based activation function is described as an implementation example. To realize time-mode operation, the presented design makes use of...

A Chip Integrity Monitor for Evaluating Long-term Encapsulation Performance Within Active Flexible Implants

One key obstacle in employing silicon integrated circuits in flexible implants is ensuring a long-term operation of the chip within the wet corrosive environment of the body. For this reason, throughout the years, various biocompatible insulating materials have been proposed, yet, evaluating their long-term encapsulation performance on...

11 nW Signal Acquisition Platform for Remote Biosensing

This paper presents the design of an extremely low-energy biosensing platform that utilizes voltage to time conversion and time-mode signal processing to sense and accommodate electrophysiological biosignals that will be later sent remotely using a simple and low power communication scheme. The electrode input is fed to a chain of monostable...

An Energy-Efficient Multi-Sensor Compressed Sensing System Employing Time-Mode Signal Processing Techniques

This paper presents the design of an ultra-low energy, rakeness-based compressed sensing (CS) system that utilizes time-mode (TM) signal processing (TMSP). To realize TM CS operation, the presented implementation makes use of monostable multivibrator based analog-to-time converters, fixed-width pulse generators, basic digital gates and an...

Design and Custom Fabrication of a Smart Temperature Sensor for an Organ-on-a-chip Platform

This paper reports on the design and fabrication of a time-mode signal-processing in situ temperature sensor customized for an organ-on-a-chip (OOC) application. The circuit was fabricated using an in-house integrated circuit (IC) technology that requires only seven lithographic steps and is compatible with MEMS fabrication process. The...