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AS5311

Datasheet - E le c t r i ca l C h a ra c t e r is t i c s

6.2.4 Tristate CMOS Output: DO

6.3 Magnetic Input Specification

Two-pole cylindrical diametrically magnetized source:

Table 7. Tristate CMOS Output

Symbol

Parameter

Conditions

Min

Typ

Max

Units

High level output voltage

VDD5V -0.5

V

Low level output voltage

VSS+0.4

V

Output current

VDD5V: 4.5V

4

mA

VDD5V: 3V

2

Table 8. Magnetic Input Specification

Symbol

Parameter

Note

Min

Typ

Max

Units

Pole length

Recommended magnet: plastic or rubber

bonded ferrite or NdFeB

1mm

Pole pair length

2

mm

Magnetic input field amplitude

Required vertical component of the

magnetic field strength on the die’s surface

10

40

mT

Magnetic offset

Constant magnetic stray field

± 5

mT

Magnetic field temperature drift

Recommended magnet: plastic or rubber

bonded ferrite or NdFeB

0.2

%/K

Magnetic input field variation

Including offset gradient

±2

%

Linear travelling speed

Incremental output: 1024 steps / polepair

including interpolation

1

1. 1) For absolute outputs, a practical speed limit is 2345 mm/s. At higher speeds, input signal cancellation will occur and the detected field

decreases due to the internal front-end. Significant signal change is indicated by the status bits.

2) With increasing speed, the distance between two samples increases. The travelling distance between two subsequent samples can

be calculated as:

where:

sampling_distance = travelling distance between samples (in mm)

v = travelling speed (in mm/sec)

fs = sampling rate in Hz (see Table 9)

650

mm/

sec

Disp

Displacement

Maximum shift between defined Hall sensor

center and magnet centerline; depends on

magnet geometries

0.5

mm

Vertical gap

Package to magnet surface;

depends on magnet strength

0.3

mm

Recommended magnet material and

temperature drift

Plastic or rubber bonded Ferrite

-0.19

%/K

Plastic or rubber bonded Neodymium

(NdFeB)

-0.12

sampling

dist

–

v

fs

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