Patent ID: 7154267

Claim:
A system comprising: a first magnetometer that produces a first output signal; a second magnetometer that produces a second output signal; an analog-to-digital signal converting means coupled to the first and second magnetometers, wherein the analog-to-digital signal converting means converts (i) the first output signal to a first digital signal, and (ii) the second output signal to a second digital signal; a processor that receives the first digital signal and the second digital signal; and a network that includes a coil located in proximity to the first and second magnetometers, wherein (i) the network is coupled to the processor, (ii) the processor provides a first voltage signal at the network for producing a first self-trimming current, and (iii) the coil generates a magnetic field in the vicinity of the first and second magnetometers when the first self-trimming current passes through the coil.