Dynamic Self-Calibrating Peak-Detecting Differential

Hall Effect Gear Tooth Sensor IC

ATS616LSG

4

Allegro MicroSystems, LLC

115 Northeast Cutoff

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

1.508.853.5000; www.allegromicro.com

REFERENCE TARGET 60+2

Characteristics

Symbol

Test Conditions

Typ.

Unit

Symbol Key

Outside Diameter

Outside diameter of target

120

mm

Ø

F

Branded Face

of Package

Air Gap

Face Width

F

Breadth of tooth, with respect

to branded face

6mm

Circular Tooth Length

t

Length of tooth, with respect to

3mm

Signature Region Cir-

cular Tooth Length

Length of signature tooth,

with respect to branded face;

15

mm

Circular Valley Length

Length of valley, with respect

to branded face; measured

3mm

Tooth Whole Depth

3mm

–

–

l

e

e

t

S

n

o

b

r

a

C

w

o

L

l

a

ir

e

t

a

M

Reference Target

Signature Region

60+2

of Package

Branded Face

Pin 4

Pin 1

Reference Target (Gear) Information

For the generation of adequate magnetic field levels, the fol-

lowing recommendations should be followed in the design and

specification of targets:

• 2 mm < tooth width, t < 4 mm

• Tooth thickness, F ≥ 3 mm

• Target material must be low carbon steel

Although these parameters apply to targets of traditional

geometry (radially oriented teeth with radial sensing, shown in

figure 1), they also can be applied in applications using stamped

targets (an aperture or rim gap punched out of the target mate-

rial) and axial sensing. For stamped geometries with axial sens-

material specification need only be considered for reference. For

example, F can now be < 3 mm.

Figure 1. Configuration with Radial-Tooth Reference Target