ATS128 datasheet(22/25 Pages) ALLEGRO

22 / 25 page

Highly Programmable, Back-Biased,

Hall-Effect Switch with TPOS Functionality

ATS128LSE

Allegro MicroSystems, LLC

115 Northeast Cutoff

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

1.508.853.5000; www.allegromicro.com

Figure 18. Example switchpoints versus mechanical location.

B+ (south)

B– (north)

Target Displacement from Home Position, θ (°)

–θ

Smaller Air Gap

(Steeper slope)

Larger Air Gap

(Shallower slope)

BRP

BOP

lower, and therefore the difference between BOP and BRP must

be considered. If BRP is more appropriate as the actual device

switchpoint, the code determined using the Up-Counting register

in the example can be programmed and set. If BOP is more appro-

priate as the switchpoint, the code determined using the Down-

Counting register can be programmed and set.

It should be noted that in the proximity sensor example given

above, the magnetic field was defined as positive (south) and

the BOP Positive, Trim Up- and Trim Down-Counting registers

were used. If in the application the magnetic field is negative,

the BOP Negative, Trim Up- and Trim Down-Counting registers

should be used as shown in figures 14C and 14D. The procedure

for programming these registers is the same as discussed in the

proximity sensor example. Note the purpose of the example is to

show how to use some of the ATS128 BOP programming options

and is not based on any reference design.

ATS128 数据表(PDF) 22 Page - Allegro MicroSystems