A 100Hz 5nT/Hz Low-Pass ¿¿ Servo-Controlled Microfluxgate Magnetometer Using Pulsed Excitation

Microfluxgate Sensors for High Frequency and Low Power Applications

“…An ASIC can dynamically adjust this bias up to 12 MHz for monolayer sensor and 73 MHz for laminated ones. It opens the path to a new generation of ultra low power and high frequency integrated systems [4].…”

“…A novel lowpass sigma-delta ASIC architecture has been demonstrated [4] that make use of short drive pulse. Lower coil resistance and sensor noise floor are the path to compact low power fluxgate making use of high quality hard axis soft magnetic thin films without magnetostriction.…”

27.9 A 200kS/s 13.5b integrated-fluxgate differential-magnetic-to-digital converter with an oversampling compensation loop for contactless current sensing

“…The offset and resolution of Hall-effect sensors is in the μT-level [1][2][3], in contrast to the nT-level accuracy of integrated-fluxgate (IFG) magnetometers [4]. Previously reported sampled-data closed-loop IFG readouts have limited BWs as their sampling frequencies (f S ) are limited to be less than or equal to the IFG excitation frequency, f EXC [5][6][7]. This paper describes a differential closed-loop IFG CCS with f S >f EXC .…”

“…Previously reported sampled-data closed-loop IFG readouts form first-order [5] or second-order MASH [6] magnetic-domain ΔΣMs or embed a SC-ΔΣM in the sense-path of an MCL with a digital loop filter and an FIRDAC (FIR filter combined with a DAC) in the feedback [7]. A challenge with embedding oversampled data-conversion into an IFG MCL is extending the readout BW independently of f EXC .…”