FGSensors FG-3+ Sensor

The FGM-X series of devices are very high sensitivity magnetic field sensors operating in the ±50 microtesla range ( ±0.5 oersted). They are simple, essentially three terminal devices, operating from a single +5 volt supply, the connections being ground, +5v and output. The output is a robust 5 volt rectangular pulse whose period is directly proportional to the field strength, (giving a frequency which varies inversely with the field), making it very easy to interface to a computer or micro controller. The typical period swing for the full range of an FGM-3 is from 8.5 μs to 25μs (~120 KHz to ~50KHz), a clear indication of its high sensitivity.

Unlike Hall Effect field sensors, which are virtually unusable in this range because of their large temperature sensitivity, the FGM-series has a very low temperature coefficient. Since the lowest effective Nyquist sampling rate is ~50 KHz, appropriate filtering can provide an AC field bandwidth from DC to ~20kHz.