An active-feedback frequency-compensation (AFFC) technique for low-power operational amplifiers is presented in this paper. With an active-feedback mechanism, a high-speed block separates the low-frequency high-gain path and high-frequency signal path such that high gain and wide bandwidth can be achieved simultaneously in the AFFC amplifier. The gain stage in the active-feedback network also r...

A transmitter front-end IC for ultrasound medical imaging applications is implemented using 30-V 0.18-mm Bipolar/CMOS/DMOS process. The proposed ultrasound transmitter front-end, consisting of voltage level-shifters and an output driver, achieves high integration and maintains good reliability while generating a 33 ns output pulse signal in order to drive a large capacitive load, which represen...

This paper presents the design, implementation and simulation of a high-gain, low-power, low-noise CMOS front-end transimpedance amplifier (TIA) for optical interfacing between a biosensor array and analog neural circuits of biohybrid robot controller along with description of Central Pattern Generator (CPG) design used for Cyberplasm based biomimetic robot controller. The proposed TIA uses an ...

The rapid and efficient exchange of ions between porous electrodes and aqueous solutions is important in many applications, such as electrical energy storage by supercapacitors, water desalination and purification by capacitive deionization, and capacitive extraction of renewable energy from a salinity difference. Here, we present a unified mean-field theory for capacitive charging and desalina...

Since the discovery of Cole and Curtis (1938. Nature (Lond.). 142:209 and 1939. J. Gen. Physiol. 22:649) that the imaginary components, i.e., capacitive and inductive components, of the admittance of squid axon membrane remained unchanged during the action potential, there have been numerous studies on impedance and admittance characteristics of nerves. First of all, it is now known that the di...

The capacitive effects of a ground plane on an aerial bucket truck undergoing periodic testing can have a significant impact on the measured test results. The capacitive coupling of a building can reduce the leakage current through the boom resulting in a lower reading from the return point of the truck. Since the coupling is not as prevalent outdoors, more current flows through the boom result...

This paper proposes a new method for the measurement of spherical coordinates by using capacitive sensors as a non-contact probe solution of measurement of aspheric surfaces. The measurement of the average effect of the capacitive probe and the influence of capacitive probe tilting were studied with respect to an eccentric spherical surface. Based on the tested characteristic curve of the avera...

This paper presents an OTA-less 2nd-order VCO-based CT ΔΣ modulator featuring a passive integrator that makes use of the VCO’s inherent parasitic effect. A low-power capacitive feedback technique is also presented for robust loop compensation. Fabricated in 40nm CMOS, the prototype occupies 0.028mm2 of active area and consumes 524μW when sampling at 330MHz. The ΔΣM achieved peak Walden FoM of 1...

Several approaches to generate electrical power directly from salinity gradient energy using capacitive electrodes have recently been developed, but power densities have remained low. By immersing the capacitive electrodes in ionic fields generated by exoelectrogenic microorganisms in bioelectrochemical reactors, we found that energy capture using synthetic river and seawater could be increased...