Highly Programmable, Back-Biased,

Hall-Effect Switch with TPOS Functionality

ATS128LSE

8

Allegro MicroSystems, LLC

115 Northeast Cutoff

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

1.508.853.5000; www.allegromicro.com

Functional Description

When the Output Polarity bit is not set (POL = 0), the ATS128

output switches on after the magnetic field at the Hall sensor IC

output switches off. The difference between the magnetic operate

In the alternative case, in which the Output Polarity bit is set

(POL = 1), the ATS128 output switches off when the magnetic

field at the Hall sensor IC exceeds the operate point threshold,

B+

V+

0

0

V+

B–

V+

B+

0

V+

B–

(A) BOPPOL = 0

POL = 0

(C) BOPPOL = 1

POL = 0

(B) BOPPOL = 0

POL = 1

(D) BOPPOL = 1

POL = 1

Figure 2. Hysteresis Diagrams. These plots demonstrate the behavior of the ATS128 with the applied magnetic field

impinging on the branded face of the device case (refer to Package Outline Drawings section). On the horizontal axis,

the B+ direction indicates increasing south or decreasing north magnetic flux density, and the B– direction indicates

increasing north or decreasing south magnetic flux density.