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Revision 1.12

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AS5311

Datasheet - A pp l ic a t io n I n f or m a t i on

The number of incremental steps per revolution can be calculated as:

(EQ 3)

(EQ 4)

Note:

The circumference (d*π) must be a multiple of one polepair = 2mm, hence the diameter of the magnet ring may need to be adjusted

accordingly:

(EQ 5)

The maximum rotational speed can be calculated as:

(EQ 6)

Where:

nbr_polepairs is the number of pole pairs at the magnet ring.

d is the diameter of the ring in mm; the diameter is taken at the locus of the Hall elements underneath the magnet.

max_rot_speed is the maximum rotational speed in revolutions per minute rpm.

max_lin_speed is the maximum linear speed in mm/sec (=650 mm/s for AS5311).

Note:

Further examples are shown in the “Magnet Selection Guide”, available for download from the

ams website.

polepairs

nbr

steps

l

incrementa

_

*

1024

_

=

2

*

*

1024

_

π

d

steps

l

incrementa

=

π

mm

polepairs

nbr

d

2

*

_

=

π

π

*

39000

*

60

*

_

max_

_

max_

d

d

speed

lin

speed

rot

=

=