Development of an ASIC preamplifier for electromagnetic sensor probes for monitoring space electromagnetic environments

Abstract

Background: Multipoint observations of plasma waves are essential for separating spatial and temporal variations of a plasma turbulence. Miniaturization and high environmental (temperature and radiation) robustness are key requirements for scientific instrument design toward a sensor network consisting of palm-sized probes. With increasing these demands, a preamplifier for the 3-axis loop antenna of an electromagnetic sensor probe has been developed by using application-specific integrated circuit (ASIC) technology with a 0.25-μm complementary metal-oxide-semiconductor process. Findings: In the present study, a new temperature compensation method is proposed by using the open-loop gain of the ASIC preamplifier with a bandgap reference (BGR) circuit. Usually, the gain is characterized by the closed-loop gain, which is governed by the accuracy of the polysilicon resistances in a chip. The open-loop gain is characterized by the effective transconductance of the ASIC preamplifier, which often has a negative temperature dependence. The temperature dependence of the gain can be dramatically improved by using the temperature-compensated BGR circuit to cancel out the negative dependence of the transconductance. The temperature dependence of the gain was about −0.01 dB/ • C in the frequency range within the closed-loop bandwidth. On the other hand, the temperature dependence of the gain at 60 kHz operating with the open-loop gain was improved from −39 × 10 −3 to −2.6 × 10 −3 dB/ • C by using the temperature-compensated BGR circuit. Moreover, the radiation robustness for the total ionizing dose (TID) level is evaluated by irradiation with gamma rays from cobalt-60. The ASIC preamplifier is not sensitive to TID effects when a thin gate oxide is used. The ASIC preamplifier showed a high radiation tolerance to at least a total ionizing dose level of 400 krad(Si). Finally, the effectiveness of the ASIC preamplifier is evaluated on the basis of a virtual sounding rocket experiment using theoretical calculations of LF standard electromagnetic waves. Conclusions: Fundamental issues (miniaturization, low-noise performance, and high environmental robustness) are solved by the presented ASIC preamplifier. The success in developing the high robustness ASIC preamplifier leads to a future mission using a lot of palm-sized probes in space.

Magnetic Search Coil (MSC) of Plasma Wave Experiment (PWE) aboard the Arase (ERG) satellite

“…Miniaturization of sensors on board the Mercury Magnetospheric Orbiter (MMO) and the Magnetospheric Multiscale (MMS) satellites has been realized using magnetic concentrators (Coillot et al 2010;Le Contel et al 2016), while maintaining a reasonable NEMI value. Drastic miniaturization of preamplifiers has been achieved by using application-specific integrated circuit (ASIC) technology (Rhouni et al 2013;Ozaki et al 2014Ozaki et al , 2016.…”

Small sensor probe for measuring plasma waves in space

“…While the design of the electric field preamplifier is basically the same with that of Kojima et al (2010), the preamplifiers of the loop antennas in the present prototype are newly designed and implemented in the ASIC chip. The details of the loop antennas and their ASIC preamplifiers will appear in the independent paper (Ozaki et al 2015). The current prototype model does not have the locator system of the sensor probe.…”

“…The combination of the loop antennas and their ASIC preamplifiers are very unique. These will appear in the independent publication in the future (Ozaki et al 2015). All of the electronic components operate at 3.3 V, which is supplied by the regulator.…”

“…We use the application-specific integrated circuit (ASIC) for the preamplifiers of magnetic field sensors and waveform receivers. While the design and performance of the ASIC waveform capture is described by Fukuhara et al (2011Fukuhara et al ( , 2012, the description of the ASIC preamplifier of the magnetic field sensor will appear in the independent paper (Ozaki et al 2015). The conventional design is used for the preamplifiers of the electric field sensors, because of the necessity of very high impedance at the input.…”

The Plasma Wave Experiment (PWE) on board the Arase (ERG) satellite

“…The disadvantage is that it consumes more power than the voltage amplifier using the flux feedback, as an equalizer is required to improve the signal dynamic range. This problem was, however, solved by low power applications using application-specific integrated circuits (ASIC) technology (Ozaki et al 2014(Ozaki et al , 2016. Three components of the magnetic field below 20 kHz detected by the MSC are fed to the WFC/OFA(B), and one component of the magnetic field along the satellite spin axis from 10 to 100 kHz is fed to the HFA.…”