11:00 AM - 1:00 PM
[PCG18-P03] Circuit Design and Performance Evaluation of Dedicated Chips for Fundamental Mode Orthogonal Fluxgate Magnetometers
Keywords:FM-OFG, ASIC, Magnetometer, nano satellite, science satellite, performance evaluation
We are working on the design of an analog circuit chip specifically for Fundamental Mode Orthogonal Fluxgate Magnetometers (FM-OFG) to be installed in future scientific satellites. Fluxgate magnetometers are often used in space missions to measure DC magnetic fields and low frequency magnetic field variations. Conventional parallel fluxgate magnetometers for space applications use ring-core sensors, which have excellent noise characteristics and output offset voltage stability. On the other hand, a sufficiently large core is required to achieve low-noise detection of magnetic field, which is not suitable for miniaturization. However, with the recent development of micro-nano satellites, there is a growing need for smaller onboard devices.
Therefore, we focused on a new type of fluxgate magnetometer. The sensor of the FM-OFG magnetometer consists of a pair of amorphous wire cores and a pickup/feedback coil. There is no need of excitation coils that are necessary for the ring-core sensor. While it is difficult to get below 10 gram per axis with a ring-core sensor, the FM-OFG sensor can be made much lighter at about 1 gram per axis.
In order to pursue smaller and lighter fluxgate magnetometers, it is also important to reduce the size of the electronic circuit. In this paper, we focus on developing an analog chip called ASIC (Application Specific Integrated Circuit) to miniaturize the electronic circuit of the FM-OFG magnetometer. The electronic circuit of the FM-OFG consists of a drive circuit that excites the wire core, and a pickup circuit that picks up the signal from the sensor head and extracts the waveform of the detected magnetic field based on a feedback configuration. In this paper, we have designed the latter circuit by using an electronic circuit simulator. In addition, the designed ASIC chip was embedded in an evaluation board and performance test was conducted.
Therefore, we focused on a new type of fluxgate magnetometer. The sensor of the FM-OFG magnetometer consists of a pair of amorphous wire cores and a pickup/feedback coil. There is no need of excitation coils that are necessary for the ring-core sensor. While it is difficult to get below 10 gram per axis with a ring-core sensor, the FM-OFG sensor can be made much lighter at about 1 gram per axis.
In order to pursue smaller and lighter fluxgate magnetometers, it is also important to reduce the size of the electronic circuit. In this paper, we focus on developing an analog chip called ASIC (Application Specific Integrated Circuit) to miniaturize the electronic circuit of the FM-OFG magnetometer. The electronic circuit of the FM-OFG consists of a drive circuit that excites the wire core, and a pickup circuit that picks up the signal from the sensor head and extracts the waveform of the detected magnetic field based on a feedback configuration. In this paper, we have designed the latter circuit by using an electronic circuit simulator. In addition, the designed ASIC chip was embedded in an evaluation board and performance test was conducted.