Voltage step up circuit for magnetometric sensor

摘要

The present invention provides an improved and simplified voltage step-up circuit (2) for a SQUID magnetometric sensor (1), which provides step-up of a voltage signal generated by a SQUID element (11). The SQUID element is exited by a modulated signal using the FLL method. In an example, a step-up means (22) comprises only one step-up transformer (22T) working at room temperature and an electronic amplifier (22A). The voltage signal is first stepped up by the transformer. A signal processing means (23) processes the stepped up signal with the modulation signal to output a magnetic field measurement signal (V phi ). In another example, a bias current source (21) is also connected to terminals between SQUID element (11) and the transformer (22). A series resistor is connected between the transformer and one of the terminals. This allows a reduction in the number of terminals between the SQUID sensor (1) and the circuit (2).