BU52001GUL_11 Datasheet, PDF (24/32 Pages) Rohm – Omnipolar Detection Hall ICs Line up of supply voltage

BU52001GUL,BU52011HFV,BU52021HFV,BU52015GUL,BU52025G,BU52053NVX,
BU52054GWZ,BU52055GWZ,BU52056NVX,BU52061NVX,BD7411G
(Magnetic Field Detection Mechanism)
Technical Note
S
N
S
S
N
S
N
Magnetic
Flux
Fig.67
Magnetic
Flux
The Hall IC cannot detect magnetic fields that run horizontal to the package top layer.
Be certain to configure the Hall IC so that the magnetic field is perpendicular to the top layer.
S
S
N
High
Magnetic
Flux
OUT [V]
High
N
N
S
Magnetic
Flux
High
Low
Bop N Brp N
N-Pole
Low
0
B
Brp S Bop S
Magnetic flux density [mT]
S-Pole
Fig.68
The bipolar detection Hall IC detects magnetic fields running perpendicular to the top surface of the package. There is an
inverse relationship between magnetic flux density and the distance separating the magnet and the Hall IC: when distance
increases magnetic density falls. When it drops below the operate point (Bop), output goes HIGH. When the magnet gets
closer to the IC and magnetic density rises, to the operate point, the output switches LOW. In LOW output mode, the
distance from the magnet to the IC increases again until the magnetic density falls to a point just below Bop, and output
returns HIGH. (This point, where magnetic flux density restores HIGH output, is known as the release point, Brp.) This
detection and adjustment mechanism is designed to prevent noise, oscillation and other erratic system operation.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
24/31
2011.12 - Rev.G