Patent ID: 7123006

Claim:
A sensing apparatus comprising: a fluxgate including a driving coil for exciting a magnetic substance core with a current, first and second current amplifiers for applying the current to first and second ends of the driving coil, a pulse generator for generating a pulse to turn on/off the first and second current amplifiers, a pulse controller for outputting a control signal allowing the pulse to be applied to the first and second current amplifiers, the pulse controller outputting the control signal at a start of a sensing cycle, the fluxgate generating an analog signal due to the excited magnetic substance; an A/D converter for converting the analog signal from the fluxgate into a digital signal, wherein the pulse controller stops outputting the control signal when the A/D converter outputs the digital signal to the pulse controller; and an AND gate for logical AND-ing the pulse from the pulse generator with the control signal from the pulse controller and for outputting an output signal to the first and second current amplifiers in accordance with the logical AND-ing.