Ultralow Noise Preamplifier Research Articles

A 1GHz Low-cost, Ultra Low-noise Preamplifier

A high quality, compact 1GHz preamplifier suitable for operation in conjunction with micro channelplates (MCP) and silicon Photomultipliers (SiPM), that is comprised of two integrated circuits is described inthis paper. The amplifier requires no adjustment and has a flat response from low frequencies and adequatebandwidth for high speed measurement systems.

Development of a Highly Flexible and High-Resolution Deep-Towed Streamer

We have developed new a deep-towed seismic streamer for sub-bottom profiling. To obtain a high-resolution seismic signal, this streamer can be operated at depths of up to 2000 m, and state-of-the-art technology is adopted with electronics circuits, that can withstand high pressures of up to 22 MPa. The streamer houses an ultra-low noise pre-amplifier, micro-processor, AD convertor, high precision clock, gain controller, and other circuitry in an oil-filled vessel. The high S/N ratio gives us high-resolution seismic images. The streamer comprises several catenated single modules and the recorded acoustic data are transmitted to the control computer with the Ethernet protocol. This makes the length of the streamer cable, and the number of hydrophones, flexible. For instance, we can use both single-channel and multi-channel streamers in the same system. Up to 24-channels can be catenated.

A low-cost, ultra-fast and ultra-low noise preamplifier for silicon avalanche photodiodes

An ultra-fast and ultra-low noise preamplifier for amplifying the fast and weak electrical signals generated by silicon avalanche photodiodes has been designed and developed. It is characterized by its simplicity, compactness, reliability and low cost of construction. A very wide bandwidth of 300 MHz, a very good linearity from 1 kHz to 280 MHz, an ultra-low noise level at the input of only 1.7 nV Hz−1/2 and a very good stability are its key features. The compact size (70 mm × 90 mm) and light weight (45 g), as well as its excellent characteristics, make this preamplifier very competitive compared to any commercial preamplifier. The preamplifier, which is a main part of the detection system of a homemade laser remote sensing system, has been successfully tested. In addition, it is versatile and can be used in any optical detection system requiring high speed and very low noise electronics.

Ultralow Noise Preamplifier and Optimization Method for Induction Magnetometers

A 2 nV/ $\surd $ Hz and 10 fA/ $\surd $ Hz at 1-Hz ultralow noise preamplifier is designed to improve the sensitivity of the induction magnetometer (IM) from 0.1 Hz to 10 kHz. Meanwhile, the noise characteristics of IM are analyzed and distinguished. A novel optimization method to find the minimum length of the core under the required noise level and the limited IM weight is proposed. Furthermore, an optimal IM prototype from 0.1 Hz to 10 kHz is developed with the noise level of 1 pT/ $\surd $ Hz at 1 Hz and 1.5 fT/ $\surd $ Hz at 2 kHz. The length is only 360 mm and the weight is 1.5 kg. The measurement results of the IM also confirm the theoretical noise model and the optimization method.

Design of low-noise preamplifier for medical diagnostic system

Experimental investigation of the developed eye tumors diagnostic system has revealed the tasks of system improvement, like reduction of the noise level of the preamplifier. The reliable solution is selection of analogue components of the preamplifier possessing as low noise level as available in the market of electronic components supply. Simultaneously, well known techniques of noise reduction should be used during the process design also. This paper discuses the design and development of the ultra-low noise preamplifier for medical applications. For the preamplifier schematic the principle of low frequency amplification with reduced the amplifier noise by n , where n is the number of amplifiers, is proposed. Using the final design of the preamplifier the noise factor value of 0.46 dB with gain of 48 dB and bandwidth of 2-35 MHz has been achieved.

Design and Characterization of a High Resolution Microfluidic Heat Flux Sensor with Thermal Modulation

A complementary metal-oxide semiconductor-compatible process was used in the design and fabrication of a suspended membrane microfluidic heat flux sensor with a thermopile for the purpose of measuring the heat flow rate. The combination of a thirty-junction gold and nickel thermoelectric sensor with an ultralow noise preamplifier, a low pass filter, and a lock-in amplifier can yield a resolution 20 nW with a sensitivity of 461 V/W. The thermal modulation method is used to eliminate low-frequency noise from the sensor output, and various amounts of fluidic heat were applied to the sensor to investigate its suitability for microfluidic applications. For sensor design and analysis of signal output, a method of modeling and simulating electro-thermal behavior in a microfluidic heat flux sensor with an integrated electronic circuit is presented and validated. The electro-thermal domain model was constructed by using system dynamics, particularly the bond graph. The electro-thermal domain system model in which the thermal and the electrical domains are coupled expresses the heat generation of samples and converts thermal input to electrical output. The proposed electro-thermal domain system model is in good agreement with the measured output voltage response in both the transient and the steady state.

An ultralow noise preamplifier for low frequency noise measurements

Low frequency noise measurements are among the most sensitive tools for the investigation of the quality and of the reliability of semiconductor devices. The sensitivity that can be obtained depends on the background noise of the low noise preamplifier coupled to the device under test (DUT) that, at very low frequencies, is dominated by flicker noise. The low frequency noise produced by the DUT, on the other end, is very often the most interesting signal to be detected and analyzed. In this work we propose a very simple topology for the realization of a general purpose low noise preamplifier whose noise performances, at very low frequencies (below 10 Hz), are significantly better than those that can be obtained by the most popular commercial instrumentation. Indeed, a gain of 80 dB with a pass band extending from a few tens of mHz up to a few kHz with an equivalent input voltage noise as low as 14 nV/square root(Hz) (100 mHz), 1.4 nV/square root(Hz) (1 Hz), 1.0 nV/square root(Hz) (10 Hz), and 0.8 nV/square root(Hz) (1 kHz) are consistently obtained by using quite standard electronic components and with no need for trimming and/or calibration steps. Moreover, the junction field-effect transistor input stage of the amplifier is characterized by an equivalent input current noise below 4 fA/square root(Hz) in the entire bandwidth, resulting in negligible background noise degradation for DUT impedances in excess of 100 kohms.

Modeling and fabrication of thin film thermopile sensor

A thin film micro heat-flux sensor using thermopile, which can measure the heat flow, was fabricated by a complementary-metal-oxide-semiconductor-compatible process. The combination of a ten-junction polysilicon and aluminum thermoelectric sensor with an ultralow noise preamplifier and low pass Butterworth filter has enabled the resolution of 3.4μW power and shows the sensitivity of 2.43mV∕μW. In order to estimate the heat generation of samples from the output measurement of a micro heat-flux sensor, a methodology for modeling and simulating electro-thermal behavior in a micro heat-flux sensor with integrated electronic circuit is presented and validated. The electro-thermal model was constructed by using system dynamics, particularly the bond graph methodology. The electro-thermal system model, where the thermal domain and the electrical domain are coupled, expresses the behavior that the heat generation of samples converts thermal input to electrical output through the system model. The proposed electro-thermal system model shows good agreement with measured voltage responses.

Superconducting radiation detector by using a microfabricated MgB2 meander line

The thermal response of an MgB2 detector was examined by using the irradiation of a 20ps pulse laser with the aid of ultra low-noise cryogenic preamplifier. High-quality MgB2 thin films were prepared by a sputtering technique. This device can be used as a novel neutron detector by employing the 10B(n,α)7Li nuclear reaction with a local energy release of 2.3MeV. This would be able to count individual neutrons with a repetition rate much faster than 106 per second.

Ultralow-noise readout circuit with an avalanche photodiode: toward a photon-number-resolving detector

The charge-integration readout circuit was fabricated to achieve an ultralow-noise preamplifier for photoelectrons generated in an avalanche photodiode with linear mode operation at 77 K. To reduce the various kinds of noise, the capacitive transimpedance amplifier was used and consisted of low-capacitance circuit elements that were cooled with liquid nitrogen. As a result, the readout noise is equal to 3.0 electrons averaged for a period of 40 ms. We discuss the requirements for avalanche photodiodes to achieve photon-number-resolving detectors below this noise level.

Polarization fluctuations near the glass transition

Measurements of polarization fluctuations were performed for an epoxy glass former. The voltage noise produced by polarization fluctuations of the sample filling a capacitor was acquired via a home-made very high input impedance current–voltage converter, in series with an ultra low noise pre-amplifier, achieving high sensitivity and accuracy in the range 0.1–1000Hz. The temperature and frequency dependence of polarization noise was investigated above and below the glass transition temperature Tg. The sample was driven to the glassy state with different cooling rate and then isothermally aged, while the noise spectral density was measured at different times and compared with the Johnson–Nyquist noise determined by the sample impedance measured by conventional dielectric spectroscopy. At thermodynamic equilibrium the polarization noise agreed with the predictions of the fluctuation–dissipation theorem linking noise spectral density to susceptibility. On the contrary, a strong violation of the theorem was observed after a fast cooling below Tg: an intense polarization noise was detected, with a power spectral density following an inverse power law frequency behavior, whose intensity was decreasing with aging time. At the same time, the amplitude of polarization fluctuations showed a non-Gaussian distribution, whose width reduced during the aging process, up to recover the Gaussian statistics on approaching the equilibrium.

A suspended membrane nanocalorimeter for ultralow volume bioanalysis

A nanocalorimetric suspended membrane sensor for pL volumes of aqueous media was fabricated by bulk silicon micromachining using anisotropic wet etching and photo and electron beam lithographic techniques. A high-temperature sensitivity of 125 microK and a rapid unfiltered time constant of 12 ms have been achieved by integrating a miniaturized reaction vessel of 0.7-nL volume on a 800-nm-thick and 300 x 300- microm2-large silicon nitride membrane, thermally insulated from the surrounding bulk silicon. The combination of a ten-junction gold and nickel thermoelectric sensor with an integrated ultralow noise preamplifier has enabled the resolution of 15-nW power in a single measurement, a result confirmed by electrical calibration. The combination of a high sensitivity and rapid response time is a consequence of miniaturization. The choice of gold and nickel as sensor material provided the maximum thermal sensitivity in the context of ease of fabrication and cost. The nanocalorimetric sensor has the potential for integration in an ultralow-volume high-density array format for the characterization of processes in which there is an exchange of heat.

Cryogenic cavity detector for a large-scale cold dark-matter axion search

An axion detector consisting of a tunable high- Q cavity, a superconducting magnet, and a superheterodyne receiver with an ultra-low noise pre-amplifier has been built to search for galactic halo axions in the mass range of 1.3–13 μeV. The detector instrumentation, search process, and data analysis are described. For the first time, this class of detector has reached sufficient sensitivity to detect halo axions with high confidence.

Ultralow-noise PC-Based measurement system for the characterization of the metallizations of integrated circuits

Low frequency noise measurements have been successfully used in research laboratories for the characterization of electromigration in interconnection lines of integrated circuits. In this paper an ultra-low noise system capable of performing such measurements contemporaneously on a statistically significant number of samples is described. The system, designed with the aim to make advantageous the utilization of the technique also in industrial environment, is controlled by a personal computer and makes available up to 255 independent input channels for noise measurements. A purposely designed ultra-low noise preamplifier and the use of an optical link between the PC and the low noise section, has allowed to obtain a total background noise which is some orders of magnitude lower than that of preexistent instrumentation.

Room temperature X-ray spectroscopy with a silicon diode detector and an ultra low noise preamplifier

An X-ray spectrograph operating at room-temperature has been designed and tested. It consists of a small area (1 mm/sup 2/) silicon diode detector on a high resistivity bulk and an ultra low noise preamplifier of new conception. A resolution of 61 RMS electrons (517 eV FWHM) was measured at 297 K, 34 RMS electrons (288 eV FWHM) at 223 K. The limits and perspectives for room temperature operation of silicon planar diode detectors and related front-end electronics are highlighted. >

Noise measurements of series SQUID arrays

Series arrays of 50 gradiometer superconducting quantum interference devices (SQUIDS) and 100 magnetometer SQUIDs have been fabricated using Nb/AlO/sub x//Nb junctions with a planarized all-refractory technology for superconductivity (PARTS), the white noise of these arrays has been measured. The individual devices are 50-pH, 2-hole and 100-pH, 1-hole SQUIDs with integrated single turn input coils, 1- mu m/sup 2/ and 0.5- mu m/sup 2/ junctions, and PtRh shunt resistors. The input coil inductance of 10 nH will effectively match with a wide bandwidth to miniature pick-up loop structures for various experiments. Ideally, the coupled energy sensitivity should remain constant as devices are added in series, while the output impedance rises to a level practical for direct coupling to room-temperature electronics. The output impedance of the arrays is 250-1000 Omega . The white noise was measured directly with an ultra low noise preamplifier at room temperature. The best result was Phi /sub N/=0.12 mu Phi /sub 0// square root Hz with a corresponding coupled energy sensitivity of 56 h. >

Ultra low-noise preamplifier for low-frequency noise measurements in electron devices

The design and realization of an ultra-low-noise, high-input-impedance amplifier for low-frequency noise measurements in electronic devices is presented. Special care is devoted to the solution of typical problems encountered in the design of low-noise low-frequency equipment, such as power supply noise and temperature fluctuations. The ultra-low-noise preamplifier has a bandwidth of over seven decades with a low-frequency roll-off of 4 mHz. The noise characteristics obtained are sensibly better than those of commercial preamplifiers commonly adopted in low-frequency noise measurements. The application of this preamplifier to the realization of standard 1/f/sup gamma / noise generators is presented. >

Advanced Antenna Design and an Ultralow-Noise Preamplifier Extend UHF Viewing Area

Combining an advanced UHF-TV antenna with a balanced-input ultralow-noise preamplifier permits over-the-air reception of UHF-TV programs in areas where there were no watchable pictures available previously.

Ultralow noise preamplifier for high impedance infrared bolometer

An ultralow noise preamplifier has been designed for use with a high impedance infrared bolometer. The preamplifier makes use of an ultralow noise field effect transistor connected to an operational amplifier in a cascode configuration. A simple regulator circuit allows the unit to be powered by any laboratory dc power supply instead of using special low noise batteries. The equivalent input noise, measured at room temperature with the input short circuited, is 1.5 nV/Hz1/2 rms at 80 Hz.

An ultralow noise preamplifier and bias supply for photoconductive infrared detectors

An ultralow noise voltage preamplifier and bias current supply using field effect transistors is described which was designed for use with a cadmium mercury telluride photoconductive infrared detector. The noise measured at room temperature with a 51 Omega source impedance and a bandwidth from 8 Hz to 10 kHz was 2 mu V peak to peak.