AK8779A Datasheet, PDF (6/13 Pages) Asahi Kasei Microsystems – Hall Effect IC for Pulse Encoders

[AK8779A]
10. Magnetic Field Detection
10.1. Definition of Vertical Magnetic Field’s Polarity
The internal signal A switches ‘L’ (ON) when the magnetic field perpendicular to the marking side of the
package exceeds BopV. When the magnetic field is reduced below BrpV, the internal signal A goes ‘H’
(OFF). Otherwise; that is, in case of the magnetic field strength is greater than BrpV and smaller than
BopV; the internal signal A keeps its status.
Line Marking
Internal signal A
BhV
N ^{BrpV 0}
B
BopV _S
Figure 4. Switching behavior of the internal signal A when vertical magnetic field is applied
10.2. Definition of Horizontal Magnetic Field’s Polarity
The internal signal B switches ‘L’ (ON) when the magnetic field parallel to the marking side of the
package exceeds BopH. When the magnetic field is reduced below BrpH, the internal signal B goes ‘H’
(OFF). Otherwise; that is, in case of the magnetic field strength is greater than BrpH and smaller than
BopH; the internal signal B keeps its status.
Line Marking
Internal signal B
BhH
N ^{BrpH 0}
B
BopH _S
Figure 5. Switching behavior of the internal signal B when horizontal magnetic field is applied
015001035-E-02
-6-
2015/07