Two-Wire, Differential, Vibration-Resistant Sensor

with Speed and Direction Output

ATS699LSN

12

Allegro MicroSystems, LLC

955 Perimeter Road

Manchester, NH 03103-3353 U.S.A.

www.allegromicro.com

Algorithms embedded in the IC’s digital controller detect the

presence of target vibration through analysis of the two magnetic

input channels.

For the –xxxxL variant, the first direction change is immediately

transmitted to the output. During any subsequent vibration, the

output is blanked and no output pulses will occur for vibrations

less than the specified vibration immunity. Output pulses contain-

ing the proper direction information will resume when direction

information is validated on constant target rotation.

For the –xxxxH variant, in the presence of vibration, output

on the amplitude and phase of the vibration. Output pulses have

stant target rotation.

Vibration Detection

t

Target

Differential

Magnetic

Profile

Normal Target Rotation

Vibration

Normal Target Rotation

Tooth

Valley

Figure 12: Output Functionality in the Presence of Running Mode Target Vibration (-xxxxL Variant)

t

Target

Differential

Magnetic

Profile

Normal Target Rotation

Vibration

Normal Target Rotation

Tooth

Valley

t

Target

Differential

Magnetic

Profile

Normal Target Rotation

Vibration

Normal Target Rotation

Tooth

Valley

Figure 13: Output Functionality in the Presence of Running Mode Target Vibration (-xxxxH Variant)