Energy efficiency of pulse shaping in electrical stimulation: the interdependence of biophysical effects and circuit design losses

Power efficiency in electrical stimulator circuits is crucial for developing large-scale multichannel applications like bidirectional brain-computer interfaces and neuroprosthetic devices. Many state-of-the-art papers have suggested that some non-rectangular pulse shapes are more energy-efficient for exciting neural excitation than the...

Pre-Filtering of Stimuli for Improved Energy Efficiency in Electrical Neural Stimulation

This work proposes a guideline for designing more energy-efficient electrical stimulators by analyzing the frequency spectrum of the stimuli. It is shown that the natural low-pass characteristic of the neuron’s membrane limits the energy transfer efficiency from the stimulator to the cell. Thus, to improve the transfer efficiency, it is proposed...

A High-Frequency Beamforming Channel for Ultrasound Stimulation and Ultrasonic Powering

New non-imaging ultrasound applications, such as ultrasound stimulation and ultrasonic power transfer, need sub-millimeter volumetric spatial resolution, electronically control of the focal spot location, high ultrasound intensity, and a tiny form factor. Satisfying these requirements demands a high-frequency phased array ultrasound transducer....

A Parasitic Resistance Extraction Tool Leveraged by Image Processing

Most academic and commercial tri-dimensional (3D) parasitic resistance extraction EDA/CAD tools rely on finite element methods (FEM) and are mainly suited to digital circuitry. In analog and mixed-signal (AMS) circuits, such as power converters and radio-frequency analog front-ends, the layout structures used for the metal interconnections...

Stent with Piezoelectric Transducers for High Spatial Resolution Ultrasound Neuromodulation- a Finite Element Analysis

Deep brain stimulation is currently the only technique used in the clinical setting to modulate the neural activity of deep brain nuclei. Recently, low-intensity transcranial focused ultrasound (LIFU) has been shown to reversibly modulate brain activity through a transcranial pathway. Transcranial LIFU requires a low-frequency ultrasound of...

Maximization of Transmitted Acoustic Intensity from Silicon Integrated Piezoelectric Ultrasound Transducers

2D phased array ultrasonic transducers realized through the combination of bulk piezoelectric ceramics and complementary metal-oxide-semiconductor (CMOS) integrated circuits (IC) are enabling a new range of wearable ultrasound therapeutic applications. Traditional therapeutic ultrasound transducers have an air backing layer to maximize...

Application of a sub-0.1-mm³ implantable mote for in vivo real-time wireless temperature sensing

There has been increasing interest in wireless, miniaturized implantable medical devices for in vivo and in situ physiological monitoring. Here, we present such an implant that uses a conventional ultrasound imager for wireless powering and data communication and acts as a probe for real-time temperature sensing, including the monitoring of...

An Integrated 2D Ultrasound Phased Array Transmitter in CMOS with Pixel Pitch-Matched Beamforming

Emerging non-imaging ultrasound applications, such as ultrasonic wireless power delivery to implantable devices and ultrasound neuromodulation, require wearable form factors, millisecond-range pulse durations and focal spot diameters approaching 100 μm with electronic control of its three-dimensional location. None of these are compatible...