A1233 Datasheet, PDF (8/12 Pages) Allegro MicroSystems – Dual-Channel Hall-Effect Direction Detection Sensor IC

A1233
Dual-Channel Hall-Effect Direction Detection Sensor IC
Application Information
Operation with Fine-Pitch Ring Magnets. For targets with a cir-
cular pitch of less than 4 mm, a performance improvement can be
observed by rotating the front face of the device (see below). This
rotation decreases the effective Hall element-to-element spacing,
provided that the Hall elements are not rotated beyond the width
of the target.
Applications. It is strongly recommended that an external 0.1 µF
bypass capacitor be connected (in close proximity to the device)
between the supply and ground of the device to
reduce both external noise and noise generated by the internal
logic.
The simplest form of magnet that will operate these devices is a
ring magnet. Other methods of operation, such as linear magnets,
are possible. Extensive applications information on magnets and
Hall-effect sensor ICs is also available in the “Hall-Effect IC
Applications Guide” which can be found on the Allegro website,
www.allegromicro.com.
Normal Coplanar Alignment
Rotated Alignment
Target Profile of Rotation
SNS
D
E1
E2
Target Circular Pitch, P
D cos α
E1
E2
α
Target Face Width, F
F < D sin α
Typical Application
(Using regulated supply; K package configuration shown)
RLOAD
V_Supply
RLOAD
A 100 Ω
2
DIR
A1233
1 _VCC
SPD ³
0.1 µF
GND
4
VDIR
CLOAD
VSPD
CLOAD
A Resistor is optional, depending on Conducted Immunity requirements
Allegro MicroSystems, LLC
8
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com