Micropower Ultrasensitive 3D Hall-Effect Switch

A1266

10

Allegro MicroSystems, LLC

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

Applications

It is strongly recommended that an external capacitor is con-

nected (in close proximity to the Hall sensor IC) between the

supply and ground of the device to reduce both external noise and

noise generated by the chopper-stabilization technique. As shown

in Figure 4, a 0.1 µF capacitor is typical.

Extensive applications information on magnets and Hall-effect

sensors is available in:

• Hall-Effect IC Applications Guide, AN27701,

• Hall-Effect Devices: Guidelines for Designing Subassemblies

Using Hall-Effect Devices AN27703.1

• Soldering Methods for Allegro’s Products – SMD and

Through-Hole, AN26009

All are provided on the Allegro website:

www.allegromicro.com

V+

0

B–

0

B+

V

OUT(HIGH)

V

OUT(SAT)

B

HYS

B

HYS

Figure 3: Switching Behavior of Omnipolar Switches

On the horizontal axis, the B+ direction indicates increasing south

polarity magnetic field strength, and the B– direction indicates

decreasing south polarity field strength (including the case of

increasing north polarity)