ZMX40M

DUAL MAGNETIC FIELD SENSOR ZMX40M DESCRIPTION This device is a special tangential field difference sensor with two AMR (Anisotropic Magneto-Resistive) bridges for field movement measurements or field comparative measurements. The ZMX40M contains two extremely sensitive magnetic sensor chips, mounted parallel to each other in an SM8 package, employing the magneto-resistive effect of thin film permalloy. It allows the measurement of magnetic fields or the detection of magnetic parts. The sensors each consist of a chip covered with thin film permalloy stripes which form a Wheatstone bridge, whose output voltage is proportional to the magnetic field component Hy. A field Hx, which is perpendicular to Hy, is necessary to suppress the hysteresis and to bias the sensors into the linear region. This field Hx is provided by an internal permanent magnet. The chips are mounted in the package 3mm apart. If a magnet travels horizontally above the sensor, each chip will give an output which will peak as the magnet passes above it and the two peaks will be spatially separated by 3mm. FEATURES Output voltage proportional to magnetic field Hy across each chip Both chips are in the same orientation and chip centres are 3mm apart in Y direction Magnetic fields vertical to the chip level Hz are not effective Disturbing fields Hx up to 30 kA/m are allowed Extremely small chip distance from the top side of package for accurate measurement When the two peaks are the same amplitude, th...