Цитат: The MR2A16A’s specification for the magnitude of an applied external field to the surface of the device is 15 Gauss (Oersted). //Да се разбира 1194 А/м, което си е доста... As a comparison, the earth’s magnetic field at its surface is less than 0.5 Gauss and the Occupational Safety and Health Administration (OSHA) require a posted warning for areas around instruments that exceed 5 Gauss. As is evident, the specification for MR2A16A exceeds these values by a wide margin.
There are two main sources of magnetic fields—current-carrying wires and permanent magnetic materials. In each case, the source’s geometry determines the extent of the magnetic field and its magnitude, which decays rapidly with increasing distance from the source.
The field's magnitude of a straight wire carrying 200 Amps, such as a starter cable for an engine with a cross-section of 1.5 centimeters, decays rapidly with distance and only exceeds the spec for MR2A16A within approximately 2 centimeters of the wire surface. For currents more realistic to circuit boards, such as 1 amp, this data can be scaled to produce fields less than 10 Gauss at distances greater than 0.2 millimeters from the conductor. Magnetic fields greater than the MR2A16A's 15 Gauss specification are unusual and can be further enhanced by system design.
The second example is a hard permanent magnet, such as a refrigerator magnet or one found in a cellular phone speaker. For example, in a tested cellular phone the highest magnitude of measured magnetic field was 90 Gauss directly at the surface of the speaker. However, within 5 millimeters of the surface the field was less than 10 Gauss and negligible beyond 1 centimeter. This magnitude should not require special design consideration in most applications and minimal physical layout optimization in special cases.
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