Marco Tartagni

A Nanocurrent Power Management IC for Low-Voltage Energy Harvesting Sources

This paper presents the nanopower design of an integrated 1-μW-to-5-mW power management circuit. The circuit integrates a boost converter with maximum power point tracking, a low drop-out voltage regulator (LDO), and a start-up circuit for battery-less activation from discharged states. The IC implements a dynamic two-way power routing policy that ensures a fast start-up from discharged states even with very large energy storage capacitors. In order to reduce the intrinsic power, asynchronous control logic was adopted. The circuit was implemented in a STMicroelectronics 0.32-μm microelectronic technology. The power conversion section and the LDO draw, respectively, stand-by currents of 121 and 414 nA in the active modes. The circuit achieves a peak conversion efficiency of 77.1% and a minimum start-up voltage of 223 mV.

Doing a Lot with a Little: Micropower Conversion and Management for Ambient-Powered Electronics

The microelectronic components integral to connecting objects in the Internet of Things require efficient power supplies. One solution is to harvest energy from the objects environment, and researchers are actively tackling problems in integrated power conversion and management to realize the vision of nanopower devices.

Optimum Design Rules for CMOS Hall Sensors

This manuscript analyzes the effects of design parameters, such as aspect ratio, doping concentration and bias, on the performance of a general CMOS Hall sensor, with insight on current-related sensitivity, power consumption, and bandwidth. The article focuses on rectangular-shaped Hall probes since this is the most general geometry leading to shape-independent results. The devices are analyzed by means of 3D-TCAD simulations embedding galvanomagnetic transport model, which takes into account the Lorentz force acting on carriers due to a magnetic field. Simulation results define a set of trade-offs and design rules that can be used by electronic designers to conceive their own Hall probes.

A Low-Noise Transimpedance Amplifier for BLM-Based Ion Channel Recording

High-throughput screening (HTS) using ion channel recording is a powerful drug discovery technique in pharmacology. Ion channel recording with planar bilayer lipid membranes (BLM) is scalable and has very high sensitivity. A HTS system based on BLM ion channel recording faces three main challenges: (i) design of scalable microfluidic devices; (ii) design of compact ultra-low-noise transimpedance amplifiers able to detect currents in the pA range with bandwidth >10 kHz; (iii) design of compact, robust and scalable systems that integrate these two elements. This paper presents a low-noise transimpedance amplifier with integrated A/D conversion realized in CMOS 0.35 μm technology. The CMOS amplifier acquires currents in the range ±200 pA and ±20 nA, with 100 kHz bandwidth while dissipating 41 mW. An integrated digital offset compensation loop balances any voltage offsets from Ag/AgCl electrodes. The measured open-input input-referred noise current is as low as 4 fA/√Hz at ±200 pA range. The current amplifier is embedded in an integrated platform, together with a microfluidic device, for current recording from ion channels. Gramicidin-A, α-haemolysin and KcsA potassium channels have been used to prove both the platform and the current-to-digital converter.

A −8 mV/+15 mV Double Polarity Piezoelectric Transformer-Based Step-Up Oscillator for Energy Harvesting Applications

This paper presents two circuit topologies of battery-less integrated boost oscillators suitable for kick-starting electronic systems in fully discharged states with ultra-low input voltages, in the context of energy harvesting applications based on thermoelectric generators, by coupling a piezoelectric transformer in a feedback loop. With respect to the prior work, the first presented solution is a double polarity circuit designed in a <inline-formula> <tex-math notation=LaTeX>

Smoothing the way towards miniaturized MEMS AlN-based piezoelectric transformers

0.18~mu text{m}

Fabrication and Electromechanical Modeling of a Flexural-Mode MEMS Piezoelectric Transformer in AlN

</tex-math></inline-formula> CMOS technology able to boost ultra-low positive and negative voltages without using switching matrixes. The circuit exploits a CMOS inverter made up of low threshold transistors, and also includes a hysteretic voltage monitor consuming only ~15 nW to enable an external circuit. The minimum achieved positive and negative oscillation voltages are +15 and −8 mV, which to the best of the authors’ knowledge, are among the lowest start-up voltages achieved in literature up to now without using magnetic components. Moreover, the input impedance in the range of several <inline-formula> <tex-math notation=LaTeX>

Non-invasive measurement of electrical conductivity of liquids in biocompatible polymeric lines for hemodialysis applications

text{k}Omega

Non-invasive soil moisture sensing based on open-ended waveguide and multivariate analysis

</tex-math></inline-formula> makes the presented solution suitable also for high impedances sources, such as rectennas. The second presented circuit, designed in a <inline-formula> <tex-math notation=LaTeX>

A Broadband, On-Chip Sensor Based on Hall Effect for Current Measurements in Smart Power Circuits

0.32~mu text{m}