This study shows that the BCI is a robust design that gives a sufficiently high output and an excellent sound quality for the hearing rehabilitation of indicated patients.
We present the design of a low-power 4-bit 1GS/s folding-flash ADC with a folding factor of two. The design of a new unbalanced double-tail dynamic comparator affords an ultra-low power operation and a high dynamic range. Unlike the conventional approaches, this design uses a fully matched input stage, an unbalanced latch stage, and a two-clock operation scheme. A combination of these features yields significant reduction of the kick-back noise, while allowing the design flexibility for adjusting the trip points of the comparators. As a result, the ADC achieves SNDR of 22.3 dB at 100MHz and 21.8 dB at 500MHz (i.e. the Nyquist frequency). The maximum INL and DNL are about 0.2 LSB. The converter consumes about 700µW from a 1-V supply yielding a figure of merit of 65fJ/conversion step. These attributes make the proposed folding-flash ADC attractive for the next-generation wireless applications.
New X-ray pixel detectors are required to cope with the demanding requirements from XFEL sources, in terms of high speed and high dynamic range. Such detectors have to provide low electronics noise to allow single photon detection at low signal intensities. At high photons intensity, a signal compression technique may be introduced to allow the detection system to cope with the required dynamic range. In this work, we propose a very simple front-end (FE) solution based on an input PMOS transistor placed on the CMOS readout chip connected to the pixel detector. The FE is optimized for low-noise readout of X-ray photons at low intensities. A gain compression when the signal intensity increases is obtained by operating the PMOSFET in the triode regime thanks to a resistor placed between the transistor and the current-readout filter. The larger is the transistor signal, the larger is the voltage drop on the resistor which pushes the transistor to operate more in triode regime at lower gain, producing a compression in the overall FE response. The FE working principle and the first experimental results obtained with a first prototype realized in the 130 nm IBM technology are presented
We introduce a hybrid CMOS-graphene sensor array for sub-second measurement of dopamine via fast-scan cyclic voltammetry (FSCV). The prototype chip has four independent CMOS readout channels, fabricated in a 65 nm process. Using planar multilayer graphene as biologically compatible sensing material enables integration of miniaturized sensing electrodes directly above the readout channels. Taking advantage of the chemical specificity of FSCV, we introduce a region of interest technique, which subtracts a large portion of the background current using a programmable low-noise constant current at about the redox potentials. We demonstrate the utility of this feature for enhancing the sensitivity by measuring the sensor response to a known dopamine concentration in vitro at three different scan rates. This strategy further allows us to significantly reduce the dynamic range requirements of the analog-to-digital converter (ADC) without compromising the measurement accuracy. We show that an integrating dual-slope ADC is adequate for digitizing the background-subtracted current. The ADC operates at a sampling frequency of 5-10 kHz and has an effective resolution of about 60 pA, which corresponds to a theoretical dopamine detection limit of about 6 nM. Our hybrid sensing platform offers an effective solution for implementing next-generation FSCV devices that can enable precise recording of dopamine signaling in vivo on a large scale.
In this work, we present a front-end stage with signal compression capability to be used in detectors for the new European XFEL in Hamburg. This front-end is an alternative solution under study for the DEPFET Sensor with Signal Compression (DSSC) detection system for the European XFEL. The DEPFET sensor of the DSSC project has a high dynamic range and very good noise performance. The high gain for small collected charge and the compression for large signals will provide both desired features of single photon detection capability and wide dynamic range. However, manufacturing of the DEPFET sensor requires a sophisticated processing technology with a relatively long time fabrication process. Accordingly, an alternative solution, namely Day-0 solution, was introduced as an approach characterized not by the best performance of the DEPFET, but available in a shorter time to allow first beam tests and experiments. The alternative sensor is made of mini Silicon Drift Detector (mini-SDD) and the compression behavior is obtained from the front-end on the readout ASIC and not by the transistor integrated in the silicon sensor, as in the DEPFET. The first version of corresponding front-end of the Day-0 solution has been realized based on an input PMOSFET transistor placed on the readout chip. This simple front-end proved the working principle of the proposed compression technique and the desired noise performance. In this paper, an improved version of the Day-0 front-end is presented. In the new prototype, the current gain of the front-end stage has been increased by factor of 1.8, the total input capacitance
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.